libgo: update to Go 1.13beta1 release

    
    Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/193497

From-SVN: r275473

342 files changed, 5040 insertions, 4249 deletions

diff --git a/libgo/misc/cgo/errors/errors_test.go b/libgo/misc/cgo/errors/errors_test.go
index 59054f4703a..e6bac0fff45 100644
--- a/libgo/misc/cgo/errors/errors_test.go
+++ b/libgo/misc/cgo/errors/errors_test.go
@@ -18,7 +18,7 @@ import (
 )
 
 func path(file string) string {
-	return filepath.Join("src", file)
+	return filepath.Join("testdata", file)
 }
 
 func check(t *testing.T, file string) {
@@ -63,7 +63,7 @@ func expect(t *testing.T, file string, errors []*regexp.Regexp) {
 	defer os.RemoveAll(dir)
 
 	dst := filepath.Join(dir, strings.TrimSuffix(file, ".go"))
-	cmd := exec.Command("go", "build", "-gcflags=-L", "-o="+dst, path(file)) // TODO(gri) no need for -gcflags=-L if go tool is adjusted
+	cmd := exec.Command("go", "build", "-gcflags=-L -e", "-o="+dst, path(file)) // TODO(gri) no need for -gcflags=-L if go tool is adjusted
 	out, err := cmd.CombinedOutput()
 	if err == nil {
 		t.Errorf("expected cgo to fail but it succeeded")
@@ -107,21 +107,10 @@ func TestReportsTypeErrors(t *testing.T) {
 	for _, file := range []string{
 		"err1.go",
 		"err2.go",
-		"err3.go",
-		"issue7757.go",
-		"issue8442.go",
 		"issue11097a.go",
 		"issue11097b.go",
-		"issue13129.go",
-		"issue13423.go",
-		"issue13467.go",
-		"issue13635.go",
-		"issue13830.go",
-		"issue16116.go",
-		"issue16591.go",
 		"issue18452.go",
 		"issue18889.go",
-		"issue26745.go",
 		"issue28721.go",
 	} {
 		check(t, file)
diff --git a/libgo/misc/cgo/errors/ptr_test.go b/libgo/misc/cgo/errors/ptr_test.go
index 254671f179e..d1ef191bf54 100644
--- a/libgo/misc/cgo/errors/ptr_test.go
+++ b/libgo/misc/cgo/errors/ptr_test.go
@@ -7,21 +7,25 @@
 package errorstest
 
 import (
-	"bufio"
 	"bytes"
+	"flag"
 	"fmt"
 	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
 	"strings"
+	"sync/atomic"
 	"testing"
 )
 
+var tmp = flag.String("tmp", "", "use `dir` for temporary files and do not clean up")
+
 // ptrTest is the tests without the boilerplate.
 type ptrTest struct {
 	name      string   // for reporting
 	c         string   // the cgo comment
+	c1        string   // cgo comment forced into non-export cgo file
 	imports   []string // a list of imports
 	support   string   // supporting functions
 	body      string   // the body of the main function
@@ -39,253 +43,248 @@ var ptrTests = []ptrTest{
 	{
 		// Passing a pointer to a struct that contains a Go pointer.
 		name: "ptr1",
-		c:    `typedef struct s { int *p; } s; void f(s *ps) {}`,
-		body: `C.f(&C.s{new(C.int)})`,
+		c:    `typedef struct s1 { int *p; } s1; void f1(s1 *ps) {}`,
+		body: `C.f1(&C.s1{new(C.int)})`,
 		fail: true,
 	},
 	{
 		// Passing a pointer to a struct that contains a Go pointer.
 		name: "ptr2",
-		c:    `typedef struct s { int *p; } s; void f(s *ps) {}`,
-		body: `p := &C.s{new(C.int)}; C.f(p)`,
+		c:    `typedef struct s2 { int *p; } s2; void f2(s2 *ps) {}`,
+		body: `p := &C.s2{new(C.int)}; C.f2(p)`,
 		fail: true,
 	},
 	{
 		// Passing a pointer to an int field of a Go struct
 		// that (irrelevantly) contains a Go pointer.
 		name: "ok1",
-		c:    `struct s { int i; int *p; }; void f(int *p) {}`,
-		body: `p := &C.struct_s{i: 0, p: new(C.int)}; C.f(&p.i)`,
+		c:    `struct s3 { int i; int *p; }; void f3(int *p) {}`,
+		body: `p := &C.struct_s3{i: 0, p: new(C.int)}; C.f3(&p.i)`,
 		fail: false,
 	},
 	{
 		// Passing a pointer to a pointer field of a Go struct.
-		name: "ptr-field",
-		c:    `struct s { int i; int *p; }; void f(int **p) {}`,
-		body: `p := &C.struct_s{i: 0, p: new(C.int)}; C.f(&p.p)`,
+		name: "ptrfield",
+		c:    `struct s4 { int i; int *p; }; void f4(int **p) {}`,
+		body: `p := &C.struct_s4{i: 0, p: new(C.int)}; C.f4(&p.p)`,
 		fail: true,
 	},
 	{
 		// Passing a pointer to a pointer field of a Go
 		// struct, where the field does not contain a Go
 		// pointer, but another field (irrelevantly) does.
-		name: "ptr-field-ok",
-		c:    `struct s { int *p1; int *p2; }; void f(int **p) {}`,
-		body: `p := &C.struct_s{p1: nil, p2: new(C.int)}; C.f(&p.p1)`,
+		name: "ptrfieldok",
+		c:    `struct s5 { int *p1; int *p2; }; void f5(int **p) {}`,
+		body: `p := &C.struct_s5{p1: nil, p2: new(C.int)}; C.f5(&p.p1)`,
 		fail: false,
 	},
 	{
 		// Passing the address of a slice with no Go pointers.
-		name:    "slice-ok-1",
-		c:       `void f(void **p) {}`,
+		name:    "sliceok1",
+		c:       `void f6(void **p) {}`,
 		imports: []string{"unsafe"},
-		body:    `s := []unsafe.Pointer{nil}; C.f(&s[0])`,
+		body:    `s := []unsafe.Pointer{nil}; C.f6(&s[0])`,
 		fail:    false,
 	},
 	{
 		// Passing the address of a slice with a Go pointer.
-		name:    "slice-ptr-1",
-		c:       `void f(void **p) {}`,
+		name:    "sliceptr1",
+		c:       `void f7(void **p) {}`,
 		imports: []string{"unsafe"},
-		body:    `i := 0; s := []unsafe.Pointer{unsafe.Pointer(&i)}; C.f(&s[0])`,
+		body:    `i := 0; s := []unsafe.Pointer{unsafe.Pointer(&i)}; C.f7(&s[0])`,
 		fail:    true,
 	},
 	{
 		// Passing the address of a slice with a Go pointer,
 		// where we are passing the address of an element that
 		// is not a Go pointer.
-		name:    "slice-ptr-2",
-		c:       `void f(void **p) {}`,
+		name:    "sliceptr2",
+		c:       `void f8(void **p) {}`,
 		imports: []string{"unsafe"},
-		body:    `i := 0; s := []unsafe.Pointer{nil, unsafe.Pointer(&i)}; C.f(&s[0])`,
+		body:    `i := 0; s := []unsafe.Pointer{nil, unsafe.Pointer(&i)}; C.f8(&s[0])`,
 		fail:    true,
 	},
 	{
 		// Passing the address of a slice that is an element
 		// in a struct only looks at the slice.
-		name:    "slice-ok-2",
-		c:       `void f(void **p) {}`,
+		name:    "sliceok2",
+		c:       `void f9(void **p) {}`,
 		imports: []string{"unsafe"},
-		support: `type S struct { p *int; s []unsafe.Pointer }`,
-		body:    `i := 0; p := &S{p:&i, s:[]unsafe.Pointer{nil}}; C.f(&p.s[0])`,
+		support: `type S9 struct { p *int; s []unsafe.Pointer }`,
+		body:    `i := 0; p := &S9{p:&i, s:[]unsafe.Pointer{nil}}; C.f9(&p.s[0])`,
 		fail:    false,
 	},
 	{
 		// Passing the address of a slice of an array that is
 		// an element in a struct, with a type conversion.
-		name:    "slice-ok-3",
-		c:       `void f(void* p) {}`,
+		name:    "sliceok3",
+		c:       `void f10(void* p) {}`,
 		imports: []string{"unsafe"},
-		support: `type S struct { p *int; a [4]byte }`,
-		body:    `i := 0; p := &S{p:&i}; s := p.a[:]; C.f(unsafe.Pointer(&s[0]))`,
+		support: `type S10 struct { p *int; a [4]byte }`,
+		body:    `i := 0; p := &S10{p:&i}; s := p.a[:]; C.f10(unsafe.Pointer(&s[0]))`,
 		fail:    false,
 	},
 	{
 		// Passing the address of a slice of an array that is
 		// an element in a struct, with a type conversion.
-		name:    "slice-ok-4",
-		c:       `typedef void* PV; void f(PV p) {}`,
+		name:    "sliceok4",
+		c:       `typedef void* PV11; void f11(PV11 p) {}`,
 		imports: []string{"unsafe"},
-		support: `type S struct { p *int; a [4]byte }`,
-		body:    `i := 0; p := &S{p:&i}; C.f(C.PV(unsafe.Pointer(&p.a[0])))`,
+		support: `type S11 struct { p *int; a [4]byte }`,
+		body:    `i := 0; p := &S11{p:&i}; C.f11(C.PV11(unsafe.Pointer(&p.a[0])))`,
 		fail:    false,
 	},
 	{
 		// Passing the address of a static variable with no
 		// pointers doesn't matter.
 		name:    "varok",
-		c:       `void f(char** parg) {}`,
-		support: `var hello = [...]C.char{'h', 'e', 'l', 'l', 'o'}`,
-		body:    `parg := [1]*C.char{&hello[0]}; C.f(&parg[0])`,
+		c:       `void f12(char** parg) {}`,
+		support: `var hello12 = [...]C.char{'h', 'e', 'l', 'l', 'o'}`,
+		body:    `parg := [1]*C.char{&hello12[0]}; C.f12(&parg[0])`,
 		fail:    false,
 	},
 	{
 		// Passing the address of a static variable with
 		// pointers does matter.
-		name:    "var",
-		c:       `void f(char*** parg) {}`,
-		support: `var hello = [...]*C.char{new(C.char)}`,
-		body:    `parg := [1]**C.char{&hello[0]}; C.f(&parg[0])`,
+		name:    "var1",
+		c:       `void f13(char*** parg) {}`,
+		support: `var hello13 = [...]*C.char{new(C.char)}`,
+		body:    `parg := [1]**C.char{&hello13[0]}; C.f13(&parg[0])`,
 		fail:    true,
 	},
 	{
 		// Storing a Go pointer into C memory should fail.
 		name: "barrier",
 		c: `#include <stdlib.h>
-                    char **f1() { return malloc(sizeof(char*)); }
-                    void f2(char **p) {}`,
-		body:      `p := C.f1(); *p = new(C.char); C.f2(p)`,
+                    char **f14a() { return malloc(sizeof(char*)); }
+                    void f14b(char **p) {}`,
+		body:      `p := C.f14a(); *p = new(C.char); C.f14b(p)`,
 		fail:      true,
 		expensive: true,
 	},
 	{
 		// Storing a Go pointer into C memory by assigning a
 		// large value should fail.
-		name: "barrier-struct",
+		name: "barrierstruct",
 		c: `#include <stdlib.h>
-                    struct s { char *a[10]; };
-                    struct s *f1() { return malloc(sizeof(struct s)); }
-                    void f2(struct s *p) {}`,
-		body:      `p := C.f1(); p.a = [10]*C.char{new(C.char)}; C.f2(p)`,
+                    struct s15 { char *a[10]; };
+                    struct s15 *f15() { return malloc(sizeof(struct s15)); }
+                    void f15b(struct s15 *p) {}`,
+		body:      `p := C.f15(); p.a = [10]*C.char{new(C.char)}; C.f15b(p)`,
 		fail:      true,
 		expensive: true,
 	},
 	{
 		// Storing a Go pointer into C memory using a slice
 		// copy should fail.
-		name: "barrier-slice",
+		name: "barrierslice",
 		c: `#include <stdlib.h>
-                    struct s { char *a[10]; };
-                    struct s *f1() { return malloc(sizeof(struct s)); }
-                    void f2(struct s *p) {}`,
-		body:      `p := C.f1(); copy(p.a[:], []*C.char{new(C.char)}); C.f2(p)`,
+                    struct s16 { char *a[10]; };
+                    struct s16 *f16() { return malloc(sizeof(struct s16)); }
+                    void f16b(struct s16 *p) {}`,
+		body:      `p := C.f16(); copy(p.a[:], []*C.char{new(C.char)}); C.f16b(p)`,
 		fail:      true,
 		expensive: true,
 	},
 	{
 		// A very large value uses a GC program, which is a
 		// different code path.
-		name: "barrier-gcprog-array",
+		name: "barriergcprogarray",
 		c: `#include <stdlib.h>
-                    struct s { char *a[32769]; };
-                    struct s *f1() { return malloc(sizeof(struct s)); }
-                    void f2(struct s *p) {}`,
-		body:      `p := C.f1(); p.a = [32769]*C.char{new(C.char)}; C.f2(p)`,
+                    struct s17 { char *a[32769]; };
+                    struct s17 *f17() { return malloc(sizeof(struct s17)); }
+                    void f17b(struct s17 *p) {}`,
+		body:      `p := C.f17(); p.a = [32769]*C.char{new(C.char)}; C.f17b(p)`,
 		fail:      true,
 		expensive: true,
 	},
 	{
 		// Similar case, with a source on the heap.
-		name: "barrier-gcprog-array-heap",
+		name: "barriergcprogarrayheap",
 		c: `#include <stdlib.h>
-                    struct s { char *a[32769]; };
-                    struct s *f1() { return malloc(sizeof(struct s)); }
-                    void f2(struct s *p) {}
-                    void f3(void *p) {}`,
+                    struct s18 { char *a[32769]; };
+                    struct s18 *f18() { return malloc(sizeof(struct s18)); }
+                    void f18b(struct s18 *p) {}
+                    void f18c(void *p) {}`,
 		imports:   []string{"unsafe"},
-		body:      `p := C.f1(); n := &[32769]*C.char{new(C.char)}; p.a = *n; C.f2(p); n[0] = nil; C.f3(unsafe.Pointer(n))`,
+		body:      `p := C.f18(); n := &[32769]*C.char{new(C.char)}; p.a = *n; C.f18b(p); n[0] = nil; C.f18c(unsafe.Pointer(n))`,
 		fail:      true,
 		expensive: true,
 	},
 	{
 		// A GC program with a struct.
-		name: "barrier-gcprog-struct",
+		name: "barriergcprogstruct",
 		c: `#include <stdlib.h>
-                    struct s { char *a[32769]; };
-                    struct s2 { struct s f; };
-                    struct s2 *f1() { return malloc(sizeof(struct s2)); }
-                    void f2(struct s2 *p) {}`,
-		body:      `p := C.f1(); p.f = C.struct_s{[32769]*C.char{new(C.char)}}; C.f2(p)`,
+                    struct s19a { char *a[32769]; };
+                    struct s19b { struct s19a f; };
+                    struct s19b *f19() { return malloc(sizeof(struct s19b)); }
+                    void f19b(struct s19b *p) {}`,
+		body:      `p := C.f19(); p.f = C.struct_s19a{[32769]*C.char{new(C.char)}}; C.f19b(p)`,
 		fail:      true,
 		expensive: true,
 	},
 	{
 		// Similar case, with a source on the heap.
-		name: "barrier-gcprog-struct-heap",
+		name: "barriergcprogstructheap",
 		c: `#include <stdlib.h>
-                    struct s { char *a[32769]; };
-                    struct s2 { struct s f; };
-                    struct s2 *f1() { return malloc(sizeof(struct s2)); }
-                    void f2(struct s2 *p) {}
-                    void f3(void *p) {}`,
+                    struct s20a { char *a[32769]; };
+                    struct s20b { struct s20a f; };
+                    struct s20b *f20() { return malloc(sizeof(struct s20b)); }
+                    void f20b(struct s20b *p) {}
+                    void f20c(void *p) {}`,
 		imports:   []string{"unsafe"},
-		body:      `p := C.f1(); n := &C.struct_s{[32769]*C.char{new(C.char)}}; p.f = *n; C.f2(p); n.a[0] = nil; C.f3(unsafe.Pointer(n))`,
+		body:      `p := C.f20(); n := &C.struct_s20a{[32769]*C.char{new(C.char)}}; p.f = *n; C.f20b(p); n.a[0] = nil; C.f20c(unsafe.Pointer(n))`,
 		fail:      true,
 		expensive: true,
 	},
 	{
 		// Exported functions may not return Go pointers.
 		name: "export1",
-		c:    `extern unsigned char *GoFn();`,
-		support: `//export GoFn
-                          func GoFn() *byte { return new(byte) }`,
-		body: `C.GoFn()`,
+		c:    `extern unsigned char *GoFn21();`,
+		support: `//export GoFn21
+                          func GoFn21() *byte { return new(byte) }`,
+		body: `C.GoFn21()`,
 		fail: true,
 	},
 	{
 		// Returning a C pointer is fine.
 		name: "exportok",
 		c: `#include <stdlib.h>
-                    extern unsigned char *GoFn();`,
-		support: `//export GoFn
-                          func GoFn() *byte { return (*byte)(C.malloc(1)) }`,
-		body: `C.GoFn()`,
+                    extern unsigned char *GoFn22();`,
+		support: `//export GoFn22
+                          func GoFn22() *byte { return (*byte)(C.malloc(1)) }`,
+		body: `C.GoFn22()`,
 	},
 	{
 		// Passing a Go string is fine.
-		name: "pass-string",
+		name: "passstring",
 		c: `#include <stddef.h>
-                    typedef struct { const char *p; ptrdiff_t n; } gostring;
-                    gostring f(gostring s) { return s; }`,
+                    typedef struct { const char *p; ptrdiff_t n; } gostring23;
+                    gostring23 f23(gostring23 s) { return s; }`,
 		imports: []string{"unsafe"},
-		body:    `s := "a"; r := C.f(*(*C.gostring)(unsafe.Pointer(&s))); if *(*string)(unsafe.Pointer(&r)) != s { panic(r) }`,
+		body:    `s := "a"; r := C.f23(*(*C.gostring23)(unsafe.Pointer(&s))); if *(*string)(unsafe.Pointer(&r)) != s { panic(r) }`,
 	},
 	{
 		// Passing a slice of Go strings fails.
-		name:    "pass-string-slice",
-		c:       `void f(void *p) {}`,
+		name:    "passstringslice",
+		c:       `void f24(void *p) {}`,
 		imports: []string{"strings", "unsafe"},
-		support: `type S struct { a [1]string }`,
-		body:    `s := S{a:[1]string{strings.Repeat("a", 2)}}; C.f(unsafe.Pointer(&s.a[0]))`,
+		support: `type S24 struct { a [1]string }`,
+		body:    `s := S24{a:[1]string{strings.Repeat("a", 2)}}; C.f24(unsafe.Pointer(&s.a[0]))`,
 		fail:    true,
 	},
 	{
 		// Exported functions may not return strings.
-		name:    "ret-string",
-		c:       `extern void f();`,
+		name:    "retstring",
+		c:       `extern void f25();`,
 		imports: []string{"strings"},
-		support: `//export GoStr
-                          func GoStr() string { return strings.Repeat("a", 2) }`,
-		body: `C.f()`,
-		extra: []extra{
-			{
-				"call.c",
-				`#include <stddef.h>
-                                 typedef struct { const char *p; ptrdiff_t n; } gostring;
-                                 extern gostring GoStr();
-                                 void f() { GoStr(); }`,
-			},
-		},
+		support: `//export GoStr25
+                          func GoStr25() string { return strings.Repeat("a", 2) }`,
+		body: `C.f25()`,
+		c1: `#include <stddef.h>
+                                 typedef struct { const char *p; ptrdiff_t n; } gostring25;
+                                 extern gostring25 GoStr25();
+                                 void f25() { GoStr25(); }`,
 		fail: true,
 	},
 	{
@@ -296,37 +295,37 @@ var ptrTests = []ptrTest{
 		// that is, we are testing something that is not unsafe.
 		name: "ptrdata1",
 		c: `#include <stdlib.h>
-                    void f(void* p) {}`,
+                    void f26(void* p) {}`,
 		imports: []string{"unsafe"},
-		support: `type S struct { p *int; a [8*8]byte; u uintptr }`,
-		body:    `i := 0; p := &S{u:uintptr(unsafe.Pointer(&i))}; q := (*S)(C.malloc(C.size_t(unsafe.Sizeof(*p)))); *q = *p; C.f(unsafe.Pointer(q))`,
+		support: `type S26 struct { p *int; a [8*8]byte; u uintptr }`,
+		body:    `i := 0; p := &S26{u:uintptr(unsafe.Pointer(&i))}; q := (*S26)(C.malloc(C.size_t(unsafe.Sizeof(*p)))); *q = *p; C.f26(unsafe.Pointer(q))`,
 		fail:    false,
 	},
 	{
 		// Like ptrdata1, but with a type that uses a GC program.
 		name: "ptrdata2",
 		c: `#include <stdlib.h>
-                    void f(void* p) {}`,
+                    void f27(void* p) {}`,
 		imports: []string{"unsafe"},
-		support: `type S struct { p *int; a [32769*8]byte; q *int; u uintptr }`,
-		body:    `i := 0; p := S{u:uintptr(unsafe.Pointer(&i))}; q := (*S)(C.malloc(C.size_t(unsafe.Sizeof(p)))); *q = p; C.f(unsafe.Pointer(q))`,
+		support: `type S27 struct { p *int; a [32769*8]byte; q *int; u uintptr }`,
+		body:    `i := 0; p := S27{u:uintptr(unsafe.Pointer(&i))}; q := (*S27)(C.malloc(C.size_t(unsafe.Sizeof(p)))); *q = p; C.f27(unsafe.Pointer(q))`,
 		fail:    false,
 	},
 	{
 		// Check deferred pointers when they are used, not
 		// when the defer statement is run.
-		name: "defer",
-		c:    `typedef struct s { int *p; } s; void f(s *ps) {}`,
-		body: `p := &C.s{}; defer C.f(p); p.p = new(C.int)`,
+		name: "defer1",
+		c:    `typedef struct s28 { int *p; } s28; void f28(s28 *ps) {}`,
+		body: `p := &C.s28{}; defer C.f28(p); p.p = new(C.int)`,
 		fail: true,
 	},
 	{
 		// Check a pointer to a union if the union has any
 		// pointer fields.
 		name:    "union1",
-		c:       `typedef union { char **p; unsigned long i; } u; void f(u *pu) {}`,
+		c:       `typedef union { char **p; unsigned long i; } u29; void f29(u29 *pu) {}`,
 		imports: []string{"unsafe"},
-		body:    `var b C.char; p := &b; C.f((*C.u)(unsafe.Pointer(&p)))`,
+		body:    `var b C.char; p := &b; C.f29((*C.u29)(unsafe.Pointer(&p)))`,
 		fail:    true,
 	},
 	{
@@ -336,55 +335,55 @@ var ptrTests = []ptrTest{
 		// integer that happens to have the same
 		// representation as a pointer.
 		name:    "union2",
-		c:       `typedef union { unsigned long i; } u; void f(u *pu) {}`,
+		c:       `typedef union { unsigned long i; } u39; void f39(u39 *pu) {}`,
 		imports: []string{"unsafe"},
-		body:    `var b C.char; p := &b; C.f((*C.u)(unsafe.Pointer(&p)))`,
+		body:    `var b C.char; p := &b; C.f39((*C.u39)(unsafe.Pointer(&p)))`,
 		fail:    false,
 	},
 	{
 		// Test preemption while entering a cgo call. Issue #21306.
-		name:    "preempt-during-call",
-		c:       `void f() {}`,
+		name:    "preemptduringcall",
+		c:       `void f30() {}`,
 		imports: []string{"runtime", "sync"},
-		body:    `var wg sync.WaitGroup; wg.Add(100); for i := 0; i < 100; i++ { go func(i int) { for j := 0; j < 100; j++ { C.f(); runtime.GOMAXPROCS(i) }; wg.Done() }(i) }; wg.Wait()`,
+		body:    `var wg sync.WaitGroup; wg.Add(100); for i := 0; i < 100; i++ { go func(i int) { for j := 0; j < 100; j++ { C.f30(); runtime.GOMAXPROCS(i) }; wg.Done() }(i) }; wg.Wait()`,
 		fail:    false,
 	},
 	{
 		// Test poller deadline with cgocheck=2.  Issue #23435.
 		name:    "deadline",
-		c:       `#define US 10`,
+		c:       `#define US31 10`,
 		imports: []string{"os", "time"},
-		body:    `r, _, _ := os.Pipe(); r.SetDeadline(time.Now().Add(C.US * time.Microsecond))`,
+		body:    `r, _, _ := os.Pipe(); r.SetDeadline(time.Now().Add(C.US31 * time.Microsecond))`,
 		fail:    false,
 	},
 	{
 		// Test for double evaluation of channel receive.
-		name:    "chan-recv",
-		c:       `void f(char** p) {}`,
+		name:    "chanrecv",
+		c:       `void f32(char** p) {}`,
 		imports: []string{"time"},
-		body:    `c := make(chan []*C.char, 2); c <- make([]*C.char, 1); go func() { time.Sleep(10 * time.Second); panic("received twice from chan") }(); C.f(&(<-c)[0]);`,
+		body:    `c := make(chan []*C.char, 2); c <- make([]*C.char, 1); go func() { time.Sleep(10 * time.Second); panic("received twice from chan") }(); C.f32(&(<-c)[0]);`,
 		fail:    false,
 	},
 	{
 		// Test that converting the address of a struct field
 		// to unsafe.Pointer still just checks that field.
 		// Issue #25941.
-		name:    "struct-field",
-		c:       `void f(void* p) {}`,
+		name:    "structfield",
+		c:       `void f33(void* p) {}`,
 		imports: []string{"unsafe"},
-		support: `type S struct { p *int; a [8]byte; u uintptr }`,
-		body:    `s := &S{p: new(int)}; C.f(unsafe.Pointer(&s.a))`,
+		support: `type S33 struct { p *int; a [8]byte; u uintptr }`,
+		body:    `s := &S33{p: new(int)}; C.f33(unsafe.Pointer(&s.a))`,
 		fail:    false,
 	},
 	{
 		// Test that converting multiple struct field
 		// addresses to unsafe.Pointer still just checks those
 		// fields. Issue #25941.
-		name:    "struct-field-2",
-		c:       `void f(void* p, int r, void* s) {}`,
+		name:    "structfield2",
+		c:       `void f34(void* p, int r, void* s) {}`,
 		imports: []string{"unsafe"},
-		support: `type S struct { a [8]byte; p *int; b int64; }`,
-		body:    `s := &S{p: new(int)}; C.f(unsafe.Pointer(&s.a), 32, unsafe.Pointer(&s.b))`,
+		support: `type S34 struct { a [8]byte; p *int; b int64; }`,
+		body:    `s := &S34{p: new(int)}; C.f34(unsafe.Pointer(&s.a), 32, unsafe.Pointer(&s.b))`,
 		fail:    false,
 	},
 	{
@@ -392,18 +391,18 @@ var ptrTests = []ptrTest{
 		// evaluated when a deferred function is deferred, not
 		// when it is run.
 		name:    "defer2",
-		c:       `void f(char **pc) {}`,
-		support: `type S1 struct { s []*C.char }; type S2 struct { ps *S1 }`,
-		body:    `p := &S2{&S1{[]*C.char{nil}}}; defer C.f(&p.ps.s[0]); p.ps = nil`,
+		c:       `void f35(char **pc) {}`,
+		support: `type S35a struct { s []*C.char }; type S35b struct { ps *S35a }`,
+		body:    `p := &S35b{&S35a{[]*C.char{nil}}}; defer C.f35(&p.ps.s[0]); p.ps = nil`,
 		fail:    false,
 	},
 	{
 		// Test that indexing into a function call still
 		// examines only the slice being indexed.
 		name:    "buffer",
-		c:       `void f(void *p) {}`,
+		c:       `void f36(void *p) {}`,
 		imports: []string{"bytes", "unsafe"},
-		body:    `var b bytes.Buffer; b.WriteString("a"); C.f(unsafe.Pointer(&b.Bytes()[0]))`,
+		body:    `var b bytes.Buffer; b.WriteString("a"); C.f36(unsafe.Pointer(&b.Bytes()[0]))`,
 		fail:    false,
 	},
 	{
@@ -411,8 +410,8 @@ var ptrTests = []ptrTest{
 		name:    "finalizer",
 		c:       `// Nothing to declare.`,
 		imports: []string{"os"},
-		support: `func open() { os.Open(os.Args[0]) }; var G [][]byte`,
-		body:    `for i := 0; i < 10000; i++ { G = append(G, make([]byte, 4096)); if i % 100 == 0 { G = nil; open() } }`,
+		support: `func open37() { os.Open(os.Args[0]) }; var G37 [][]byte`,
+		body:    `for i := 0; i < 10000; i++ { G37 = append(G37, make([]byte, 4096)); if i % 100 == 0 { G37 = nil; open37() } }`,
 		fail:    false,
 	},
 	{
@@ -420,98 +419,159 @@ var ptrTests = []ptrTest{
 		name:    "structof",
 		c:       `// Nothing to declare.`,
 		imports: []string{"reflect"},
-		support: `type MyInt int; func (i MyInt) Get() int { return int(i) }; type Getter interface { Get() int }`,
-		body:    `t := reflect.StructOf([]reflect.StructField{{Name: "MyInt", Type: reflect.TypeOf(MyInt(0)), Anonymous: true}}); v := reflect.New(t).Elem(); v.Interface().(Getter).Get()`,
+		support: `type MyInt38 int; func (i MyInt38) Get() int { return int(i) }; type Getter38 interface { Get() int }`,
+		body:    `t := reflect.StructOf([]reflect.StructField{{Name: "MyInt38", Type: reflect.TypeOf(MyInt38(0)), Anonymous: true}}); v := reflect.New(t).Elem(); v.Interface().(Getter38).Get()`,
 		fail:    false,
 	},
 }
 
 func TestPointerChecks(t *testing.T) {
+	dir, exe := buildPtrTests(t)
+
+	// We (TestPointerChecks) return before the parallel subtest functions do,
+	// so we can't just defer os.RemoveAll(dir). Instead we have to wait for
+	// the parallel subtests to finish. This code looks racy but is not:
+	// the add +1 run in serial before testOne blocks. The -1 run in parallel
+	// after testOne finishes.
+	var pending int32
 	for _, pt := range ptrTests {
 		pt := pt
 		t.Run(pt.name, func(t *testing.T) {
-			testOne(t, pt)
+			atomic.AddInt32(&pending, +1)
+			defer func() {
+				if atomic.AddInt32(&pending, -1) == 0 {
+					os.RemoveAll(dir)
+				}
+			}()
+			testOne(t, pt, exe)
 		})
 	}
 }
 
-func testOne(t *testing.T, pt ptrTest) {
-	t.Parallel()
-
-	gopath, err := ioutil.TempDir("", filepath.Base(t.Name()))
-	if err != nil {
-		t.Fatal(err)
+func buildPtrTests(t *testing.T) (dir, exe string) {
+	var gopath string
+	if *tmp != "" {
+		gopath = *tmp
+		dir = ""
+	} else {
+		d, err := ioutil.TempDir("", filepath.Base(t.Name()))
+		if err != nil {
+			t.Fatal(err)
+		}
+		dir = d
+		gopath = d
 	}
-	defer os.RemoveAll(gopath)
 
-	src := filepath.Join(gopath, "src")
-	if err := os.Mkdir(src, 0777); err != nil {
+	src := filepath.Join(gopath, "src", "ptrtest")
+	if err := os.MkdirAll(src, 0777); err != nil {
 		t.Fatal(err)
 	}
 
-	name := filepath.Join(src, fmt.Sprintf("%s.go", filepath.Base(t.Name())))
-	f, err := os.Create(name)
-	if err != nil {
-		t.Fatal(err)
-	}
+	// Prepare two cgo inputs: one for standard cgo and one for //export cgo.
+	// (The latter cannot have C definitions, only declarations.)
+	var cgo1, cgo2 bytes.Buffer
+	fmt.Fprintf(&cgo1, "package main\n\n/*\n")
+	fmt.Fprintf(&cgo2, "package main\n\n/*\n")
 
-	b := bufio.NewWriter(f)
-	fmt.Fprintln(b, `package main`)
-	fmt.Fprintln(b)
-	fmt.Fprintln(b, `/*`)
-	fmt.Fprintln(b, pt.c)
-	fmt.Fprintln(b, `*/`)
-	fmt.Fprintln(b, `import "C"`)
-	fmt.Fprintln(b)
-	for _, imp := range pt.imports {
-		fmt.Fprintln(b, `import "`+imp+`"`)
-	}
-	if len(pt.imports) > 0 {
-		fmt.Fprintln(b)
-	}
-	if len(pt.support) > 0 {
-		fmt.Fprintln(b, pt.support)
-		fmt.Fprintln(b)
+	// C code
+	for _, pt := range ptrTests {
+		cgo := &cgo1
+		if strings.Contains(pt.support, "//export") {
+			cgo = &cgo2
+		}
+		fmt.Fprintf(cgo, "%s\n", pt.c)
+		fmt.Fprintf(&cgo1, "%s\n", pt.c1)
 	}
-	fmt.Fprintln(b, `func main() {`)
-	fmt.Fprintln(b, pt.body)
-	fmt.Fprintln(b, `}`)
+	fmt.Fprintf(&cgo1, "*/\nimport \"C\"\n\n")
+	fmt.Fprintf(&cgo2, "*/\nimport \"C\"\n\n")
 
-	if err := b.Flush(); err != nil {
-		t.Fatalf("flushing %s: %v", name, err)
-	}
-	if err := f.Close(); err != nil {
-		t.Fatalf("closing %s: %v", name, err)
+	// Imports
+	did1 := make(map[string]bool)
+	did2 := make(map[string]bool)
+	did1["os"] = true // for ptrTestMain
+	fmt.Fprintf(&cgo1, "import \"os\"\n")
+
+	for _, pt := range ptrTests {
+		did := did1
+		cgo := &cgo1
+		if strings.Contains(pt.support, "//export") {
+			did = did2
+			cgo = &cgo2
+		}
+		for _, imp := range pt.imports {
+			if !did[imp] {
+				did[imp] = true
+				fmt.Fprintf(cgo, "import %q\n", imp)
+			}
+		}
 	}
 
-	for _, e := range pt.extra {
-		if err := ioutil.WriteFile(filepath.Join(src, e.name), []byte(e.contents), 0644); err != nil {
-			t.Fatalf("writing %s: %v", e.name, err)
+	// Func support and bodies.
+	for _, pt := range ptrTests {
+		cgo := &cgo1
+		if strings.Contains(pt.support, "//export") {
+			cgo = &cgo2
 		}
+		fmt.Fprintf(cgo, "%s\nfunc %s() {\n%s\n}\n", pt.support, pt.name, pt.body)
 	}
 
-	args := func(cmd *exec.Cmd) string {
-		return strings.Join(cmd.Args, " ")
+	// Func list and main dispatch.
+	fmt.Fprintf(&cgo1, "var funcs = map[string]func() {\n")
+	for _, pt := range ptrTests {
+		fmt.Fprintf(&cgo1, "\t%q: %s,\n", pt.name, pt.name)
 	}
+	fmt.Fprintf(&cgo1, "}\n\n")
+	fmt.Fprintf(&cgo1, "%s\n", ptrTestMain)
 
-	cmd := exec.Command("go", "build")
+	if err := ioutil.WriteFile(filepath.Join(src, "cgo1.go"), cgo1.Bytes(), 0666); err != nil {
+		t.Fatal(err)
+	}
+	if err := ioutil.WriteFile(filepath.Join(src, "cgo2.go"), cgo2.Bytes(), 0666); err != nil {
+		t.Fatal(err)
+	}
+
+	cmd := exec.Command("go", "build", "-o", "ptrtest.exe")
 	cmd.Dir = src
 	cmd.Env = append(os.Environ(), "GOPATH="+gopath)
-	buf, err := cmd.CombinedOutput()
+	out, err := cmd.CombinedOutput()
 	if err != nil {
-		t.Logf("%#q:\n%s", args(cmd), buf)
-		t.Fatalf("failed to build: %v", err)
+		t.Fatalf("go build: %v\n%s", err, out)
 	}
 
-	exe := filepath.Join(src, filepath.Base(src))
-	cmd = exec.Command(exe)
-	cmd.Dir = src
+	return dir, filepath.Join(src, "ptrtest.exe")
+}
+
+const ptrTestMain = `
+func main() {
+	for _, arg := range os.Args[1:] {
+		f := funcs[arg]
+		if f == nil {
+			panic("missing func "+arg)
+		}
+		f()
+	}
+}
+`
+
+var csem = make(chan bool, 16)
+
+func testOne(t *testing.T, pt ptrTest, exe string) {
+	t.Parallel()
+
+	// Run the tests in parallel, but don't run too many
+	// executions in parallel, to avoid overloading the system.
+	runcmd := func(cgocheck string) ([]byte, error) {
+		csem <- true
+		defer func() { <-csem }()
+		cmd := exec.Command(exe, pt.name)
+		cmd.Env = append(os.Environ(), "GODEBUG=cgocheck="+cgocheck)
+		return cmd.CombinedOutput()
+	}
 
 	if pt.expensive {
-		cmd.Env = cgocheckEnv("1")
-		buf, err := cmd.CombinedOutput()
+		buf, err := runcmd("1")
 		if err != nil {
-			t.Logf("%#q:\n%s", args(cmd), buf)
+			t.Logf("%s", buf)
 			if pt.fail {
 				t.Fatalf("test marked expensive, but failed when not expensive: %v", err)
 			} else {
@@ -519,54 +579,43 @@ func testOne(t *testing.T, pt ptrTest) {
 			}
 		}
 
-		cmd = exec.Command(exe)
-		cmd.Dir = src
 	}
 
+	cgocheck := ""
 	if pt.expensive {
-		cmd.Env = cgocheckEnv("2")
+		cgocheck = "2"
 	}
 
-	buf, err = cmd.CombinedOutput()
+	buf, err := runcmd(cgocheck)
 	if pt.fail {
 		if err == nil {
-			t.Logf("%#q:\n%s", args(cmd), buf)
+			t.Logf("%s", buf)
 			t.Fatalf("did not fail as expected")
 		} else if !bytes.Contains(buf, []byte("Go pointer")) {
-			t.Logf("%#q:\n%s", args(cmd), buf)
+			t.Logf("%s", buf)
 			t.Fatalf("did not print expected error (failed with %v)", err)
 		}
 	} else {
 		if err != nil {
-			t.Logf("%#q:\n%s", args(cmd), buf)
+			t.Logf("%s", buf)
 			t.Fatalf("failed unexpectedly: %v", err)
 		}
 
 		if !pt.expensive {
 			// Make sure it passes with the expensive checks.
-			cmd := exec.Command(exe)
-			cmd.Dir = src
-			cmd.Env = cgocheckEnv("2")
-			buf, err := cmd.CombinedOutput()
+			buf, err := runcmd("2")
 			if err != nil {
-				t.Logf("%#q:\n%s", args(cmd), buf)
+				t.Logf("%s", buf)
 				t.Fatalf("failed unexpectedly with expensive checks: %v", err)
 			}
 		}
 	}
 
 	if pt.fail {
-		cmd = exec.Command(exe)
-		cmd.Dir = src
-		cmd.Env = cgocheckEnv("0")
-		buf, err := cmd.CombinedOutput()
+		buf, err := runcmd("0")
 		if err != nil {
-			t.Logf("%#q:\n%s", args(cmd), buf)
+			t.Logf("%s", buf)
 			t.Fatalf("failed unexpectedly with GODEBUG=cgocheck=0: %v", err)
 		}
 	}
 }
-
-func cgocheckEnv(val string) []string {
-	return append(os.Environ(), "GODEBUG=cgocheck="+val)
-}
diff --git a/libgo/misc/cgo/errors/src/err2.go b/libgo/misc/cgo/errors/src/err2.go
deleted file mode 100644
index 3ab410bbaac..00000000000
--- a/libgo/misc/cgo/errors/src/err2.go
+++ /dev/null
@@ -1,13 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-import "C"
-
-func main() {
-	s := ""
-	_ = s
-	C.malloc(s) // ERROR HERE
-}
diff --git a/libgo/misc/cgo/errors/src/err3.go b/libgo/misc/cgo/errors/src/err3.go
deleted file mode 100644
index 609e1a0b748..00000000000
--- a/libgo/misc/cgo/errors/src/err3.go
+++ /dev/null
@@ -1,18 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-/*
-typedef struct foo foo_t;
-typedef struct bar bar_t;
-
-foo_t *foop;
-*/
-import "C"
-
-func main() {
-	x := (*C.bar_t)(nil)
-	C.foop = x // ERROR HERE
-}
diff --git a/libgo/misc/cgo/errors/src/issue13129.go b/libgo/misc/cgo/errors/src/issue13129.go
deleted file mode 100644
index 057bce4b829..00000000000
--- a/libgo/misc/cgo/errors/src/issue13129.go
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// issue 13129: used to output error about C.unsignedshort with CC=clang
-
-package main
-
-import "C"
-
-func main() {
-	var x C.ushort
-	x = int(0) // ERROR HERE: C\.ushort
-}
diff --git a/libgo/misc/cgo/errors/src/issue13423.go b/libgo/misc/cgo/errors/src/issue13423.go
deleted file mode 100644
index fc191572376..00000000000
--- a/libgo/misc/cgo/errors/src/issue13423.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-// #include <stdio.h>
-import "C"
-
-func main() {
-	_ = C.fopen() // ERROR HERE
-}
diff --git a/libgo/misc/cgo/errors/src/issue13467.go b/libgo/misc/cgo/errors/src/issue13467.go
deleted file mode 100644
index e061880ddab..00000000000
--- a/libgo/misc/cgo/errors/src/issue13467.go
+++ /dev/null
@@ -1,15 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package p
-
-/*
-static int transform(int x) { return x; }
-*/
-import "C"
-
-func F() {
-	var x rune = '✈'
-	var _ rune = C.transform(x) // ERROR HERE: C\.int
-}
diff --git a/libgo/misc/cgo/errors/src/issue13635.go b/libgo/misc/cgo/errors/src/issue13635.go
deleted file mode 100644
index 3f38f5df4b5..00000000000
--- a/libgo/misc/cgo/errors/src/issue13635.go
+++ /dev/null
@@ -1,24 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// issue 13635: used to output error about C.unsignedchar.
-// This test tests all such types.
-
-package pkg
-
-import "C"
-
-func main() {
-	var (
-		_ C.uchar         = "uc"  // ERROR HERE: C\.uchar
-		_ C.schar         = "sc"  // ERROR HERE: C\.schar
-		_ C.ushort        = "us"  // ERROR HERE: C\.ushort
-		_ C.uint          = "ui"  // ERROR HERE: C\.uint
-		_ C.ulong         = "ul"  // ERROR HERE: C\.ulong
-		_ C.longlong      = "ll"  // ERROR HERE: C\.longlong
-		_ C.ulonglong     = "ull" // ERROR HERE: C\.ulonglong
-		_ C.complexfloat  = "cf"  // ERROR HERE: C\.complexfloat
-		_ C.complexdouble = "cd"  // ERROR HERE: C\.complexdouble
-	)
-}
diff --git a/libgo/misc/cgo/errors/src/issue13830.go b/libgo/misc/cgo/errors/src/issue13830.go
deleted file mode 100644
index ac20c82b81b..00000000000
--- a/libgo/misc/cgo/errors/src/issue13830.go
+++ /dev/null
@@ -1,26 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// cgo converts C void* to Go unsafe.Pointer, so despite appearances C
-// void** is Go *unsafe.Pointer. This test verifies that we detect the
-// problem at build time.
-
-package main
-
-// typedef void v;
-// void F(v** p) {}
-import "C"
-
-import "unsafe"
-
-type v [0]byte
-
-func f(p **v) {
-	C.F((**C.v)(unsafe.Pointer(p))) // ERROR HERE
-}
-
-func main() {
-	var p *v
-	f(&p)
-}
diff --git a/libgo/misc/cgo/errors/src/issue16116.go b/libgo/misc/cgo/errors/src/issue16116.go
deleted file mode 100644
index 1e01cab844e..00000000000
--- a/libgo/misc/cgo/errors/src/issue16116.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-// void f(void *p, int x) {}
-import "C"
-
-func main() {
-	_ = C.f(1) // ERROR HERE
-}
diff --git a/libgo/misc/cgo/errors/src/issue16591.go b/libgo/misc/cgo/errors/src/issue16591.go
deleted file mode 100644
index 10eb8403cf8..00000000000
--- a/libgo/misc/cgo/errors/src/issue16591.go
+++ /dev/null
@@ -1,17 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 16591: Test that we detect an invalid call that was being
-// hidden by a type conversion inserted by cgo checking.
-
-package p
-
-// void f(int** p) { }
-import "C"
-
-type x *C.int
-
-func F(p *x) {
-	C.f(p) // ERROR HERE
-}
diff --git a/libgo/misc/cgo/errors/src/issue26745.go b/libgo/misc/cgo/errors/src/issue26745.go
deleted file mode 100644
index 0e224538db6..00000000000
--- a/libgo/misc/cgo/errors/src/issue26745.go
+++ /dev/null
@@ -1,17 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-// int a;
-// void CF(int i) {}
-import "C"
-
-func F1(i int) int {
-	return C.a + 1 // ERROR HERE: :13
-}
-
-func F2(i int) {
-	C.CF(i) // ERROR HERE: :6
-}
diff --git a/libgo/misc/cgo/errors/src/issue7757.go b/libgo/misc/cgo/errors/src/issue7757.go
deleted file mode 100644
index 0426e9fb7ef..00000000000
--- a/libgo/misc/cgo/errors/src/issue7757.go
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-/*
-void foo() {}
-*/
-import "C"
-
-func main() {
-	C.foo = C.foo // ERROR HERE
-}
diff --git a/libgo/misc/cgo/errors/src/issue8442.go b/libgo/misc/cgo/errors/src/issue8442.go
deleted file mode 100644
index 60477ad345e..00000000000
--- a/libgo/misc/cgo/errors/src/issue8442.go
+++ /dev/null
@@ -1,17 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package main
-
-// Issue 8442.  Cgo output unhelpful error messages for
-// invalid C preambles.
-
-/*
-void issue8442foo(UNDEF*); // ERROR HERE
-*/
-import "C"
-
-func main() {
-	C.issue8442foo(nil)
-}
diff --git a/libgo/misc/cgo/errors/src/err1.go b/libgo/misc/cgo/errors/testdata/err1.go
index 2c232cf58a7..ced7443599b 100644
--- a/libgo/misc/cgo/errors/src/err1.go
+++ b/libgo/misc/cgo/errors/testdata/err1.go
@@ -10,6 +10,10 @@ package main
 void test() {
 	xxx;		// ERROR HERE
 }
+
+// Issue 8442.  Cgo output unhelpful error messages for
+// invalid C preambles.
+void issue8442foo(UNDEF*); // ERROR HERE
 */
 import "C"
 
diff --git a/libgo/misc/cgo/errors/testdata/err2.go b/libgo/misc/cgo/errors/testdata/err2.go
new file mode 100644
index 00000000000..1d22401aee5
--- /dev/null
+++ b/libgo/misc/cgo/errors/testdata/err2.go
@@ -0,0 +1,102 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+/*
+#include <stdio.h>
+
+typedef struct foo foo_t;
+typedef struct bar bar_t;
+
+foo_t *foop;
+
+long double x = 0;
+
+static int transform(int x) { return x; }
+
+typedef void v;
+void F(v** p) {}
+
+void fvi(void *p, int x) {}
+
+void fppi(int** p) {}
+
+int i;
+void fi(int i) {}
+*/
+import "C"
+import (
+	"unsafe"
+)
+
+func main() {
+	s := ""
+	_ = s
+	C.malloc(s) // ERROR HERE
+
+	x := (*C.bar_t)(nil)
+	C.foop = x // ERROR HERE
+
+	// issue 13129: used to output error about C.unsignedshort with CC=clang
+	var x C.ushort
+	x = int(0) // ERROR HERE: C\.ushort
+
+	// issue 13423
+	_ = C.fopen() // ERROR HERE
+
+	// issue 13467
+	var x rune = '✈'
+	var _ rune = C.transform(x) // ERROR HERE: C\.int
+
+	// issue 13635: used to output error about C.unsignedchar.
+	// This test tests all such types.
+	var (
+		_ C.uchar         = "uc"  // ERROR HERE: C\.uchar
+		_ C.schar         = "sc"  // ERROR HERE: C\.schar
+		_ C.ushort        = "us"  // ERROR HERE: C\.ushort
+		_ C.uint          = "ui"  // ERROR HERE: C\.uint
+		_ C.ulong         = "ul"  // ERROR HERE: C\.ulong
+		_ C.longlong      = "ll"  // ERROR HERE: C\.longlong
+		_ C.ulonglong     = "ull" // ERROR HERE: C\.ulonglong
+		_ C.complexfloat  = "cf"  // ERROR HERE: C\.complexfloat
+		_ C.complexdouble = "cd"  // ERROR HERE: C\.complexdouble
+	)
+
+	// issue 13830
+	// cgo converts C void* to Go unsafe.Pointer, so despite appearances C
+	// void** is Go *unsafe.Pointer. This test verifies that we detect the
+	// problem at build time.
+	{
+		type v [0]byte
+
+		f := func(p **v) {
+			C.F((**C.v)(unsafe.Pointer(p))) // ERROR HERE
+		}
+		var p *v
+		f(&p)
+	}
+
+	// issue 16116
+	_ = C.fvi(1) // ERROR HERE
+
+	// Issue 16591: Test that we detect an invalid call that was being
+	// hidden by a type conversion inserted by cgo checking.
+	{
+		type x *C.int
+		var p *x
+		C.fppi(p) // ERROR HERE
+	}
+
+	// issue 26745
+	_ = func(i int) int {
+		return C.i + 1 // ERROR HERE: :13
+	}
+	_ = func(i int) {
+		C.fi(i) // ERROR HERE: :6
+	}
+
+	C.fi = C.fi // ERROR HERE
+
+}
diff --git a/libgo/misc/cgo/errors/src/err4.go b/libgo/misc/cgo/errors/testdata/err4.go
index 8e5f78e987b..8e5f78e987b 100644
--- a/libgo/misc/cgo/errors/src/err4.go
+++ b/libgo/misc/cgo/errors/testdata/err4.go
diff --git a/libgo/misc/cgo/errors/src/issue11097a.go b/libgo/misc/cgo/errors/testdata/issue11097a.go
index 028d10ce5cb..028d10ce5cb 100644
--- a/libgo/misc/cgo/errors/src/issue11097a.go
+++ b/libgo/misc/cgo/errors/testdata/issue11097a.go
diff --git a/libgo/misc/cgo/errors/src/issue11097b.go b/libgo/misc/cgo/errors/testdata/issue11097b.go
index b00f24fc103..b00f24fc103 100644
--- a/libgo/misc/cgo/errors/src/issue11097b.go
+++ b/libgo/misc/cgo/errors/testdata/issue11097b.go
diff --git a/libgo/misc/cgo/errors/src/issue14669.go b/libgo/misc/cgo/errors/testdata/issue14669.go
index 04d2bcb631d..04d2bcb631d 100644
--- a/libgo/misc/cgo/errors/src/issue14669.go
+++ b/libgo/misc/cgo/errors/testdata/issue14669.go
diff --git a/libgo/misc/cgo/errors/src/issue18452.go b/libgo/misc/cgo/errors/testdata/issue18452.go
index 0386d768927..0386d768927 100644
--- a/libgo/misc/cgo/errors/src/issue18452.go
+++ b/libgo/misc/cgo/errors/testdata/issue18452.go
diff --git a/libgo/misc/cgo/errors/src/issue18889.go b/libgo/misc/cgo/errors/testdata/issue18889.go
index bba6b8f9bb1..bba6b8f9bb1 100644
--- a/libgo/misc/cgo/errors/src/issue18889.go
+++ b/libgo/misc/cgo/errors/testdata/issue18889.go
diff --git a/libgo/misc/cgo/errors/src/issue28069.go b/libgo/misc/cgo/errors/testdata/issue28069.go
index e19a3b45bd5..e19a3b45bd5 100644
--- a/libgo/misc/cgo/errors/src/issue28069.go
+++ b/libgo/misc/cgo/errors/testdata/issue28069.go
diff --git a/libgo/misc/cgo/errors/src/issue28721.go b/libgo/misc/cgo/errors/testdata/issue28721.go
index 0eb2a9271c2..0eb2a9271c2 100644
--- a/libgo/misc/cgo/errors/src/issue28721.go
+++ b/libgo/misc/cgo/errors/testdata/issue28721.go
diff --git a/libgo/misc/cgo/errors/src/long_double_size.go b/libgo/misc/cgo/errors/testdata/long_double_size.go
index 8b797f886ae..8b797f886ae 100644
--- a/libgo/misc/cgo/errors/src/long_double_size.go
+++ b/libgo/misc/cgo/errors/testdata/long_double_size.go
diff --git a/libgo/misc/cgo/errors/src/malloc.go b/libgo/misc/cgo/errors/testdata/malloc.go
index 65da0208b97..65da0208b97 100644
--- a/libgo/misc/cgo/errors/src/malloc.go
+++ b/libgo/misc/cgo/errors/testdata/malloc.go
diff --git a/libgo/misc/cgo/fortran/test.bash b/libgo/misc/cgo/fortran/test.bash
index 1e0d59ea1c6..9498da0208f 100644
--- a/libgo/misc/cgo/fortran/test.bash
+++ b/libgo/misc/cgo/fortran/test.bash
@@ -14,12 +14,17 @@ goos=$(go env GOOS)
 libext="so"
 if [ "$goos" = "darwin" ]; then
 	libext="dylib"
+elif [ "$goos" = "aix" ]; then
+	libtext="a"
 fi
 
 case "$FC" in
 *gfortran*)
   libpath=$(dirname $($FC -print-file-name=libgfortran.$libext))
-  export CGO_LDFLAGS="$CGO_LDFLAGS -Wl,-rpath,$libpath -L $libpath"
+  if [ "$goos" != "aix" ]; then
+	  RPATH_FLAG="-Wl,-rpath,$libpath"
+  fi
+  export CGO_LDFLAGS="$CGO_LDFLAGS $RPATH_FLAG -L $libpath"
   ;;
 esac
 
diff --git a/libgo/misc/cgo/life/life_test.go b/libgo/misc/cgo/life/life_test.go
new file mode 100644
index 00000000000..3c95d87d8ad
--- /dev/null
+++ b/libgo/misc/cgo/life/life_test.go
@@ -0,0 +1,64 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package life_test
+
+import (
+	"bytes"
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestMain(m *testing.M) {
+	log.SetFlags(log.Lshortfile)
+	os.Exit(testMain(m))
+}
+
+func testMain(m *testing.M) int {
+	GOPATH, err := ioutil.TempDir("", "cgolife")
+	if err != nil {
+		log.Panic(err)
+	}
+	defer os.RemoveAll(GOPATH)
+	os.Setenv("GOPATH", GOPATH)
+
+	// Copy testdata into GOPATH/src/cgolife, along with a go.mod file
+	// declaring the same path.
+	modRoot := filepath.Join(GOPATH, "src", "cgolife")
+	if err := overlayDir(modRoot, "testdata"); err != nil {
+		log.Panic(err)
+	}
+	if err := os.Chdir(modRoot); err != nil {
+		log.Panic(err)
+	}
+	os.Setenv("PWD", modRoot)
+	if err := ioutil.WriteFile("go.mod", []byte("module cgolife\n"), 0666); err != nil {
+		log.Panic(err)
+	}
+
+	return m.Run()
+}
+
+func TestTestRun(t *testing.T) {
+	if os.Getenv("GOOS") == "android" {
+		t.Skip("the go tool runs with CGO_ENABLED=0 on the android device")
+	}
+	out, err := exec.Command("go", "env", "GOROOT").Output()
+	if err != nil {
+		t.Fatal(err)
+	}
+	GOROOT := string(bytes.TrimSpace(out))
+
+	cmd := exec.Command("go", "run", filepath.Join(GOROOT, "test", "run.go"), "-", ".")
+	out, err = cmd.CombinedOutput()
+	if err != nil {
+		t.Fatalf("%s: %s\n%s", strings.Join(cmd.Args, " "), err, out)
+	}
+	t.Logf("%s:\n%s", strings.Join(cmd.Args, " "), out)
+}
diff --git a/libgo/misc/cgo/life/overlaydir_test.go b/libgo/misc/cgo/life/overlaydir_test.go
new file mode 100644
index 00000000000..f381ea62f3b
--- /dev/null
+++ b/libgo/misc/cgo/life/overlaydir_test.go
@@ -0,0 +1,81 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package life_test
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// overlayDir makes a minimal-overhead copy of srcRoot in which new files may be added.
+//
+// TODO: Once we no longer need to support the misc module in GOPATH mode,
+// factor this function out into a package to reduce duplication.
+func overlayDir(dstRoot, srcRoot string) error {
+	dstRoot = filepath.Clean(dstRoot)
+	if err := os.MkdirAll(dstRoot, 0777); err != nil {
+		return err
+	}
+
+	symBase, err := filepath.Rel(srcRoot, dstRoot)
+	if err != nil {
+		symBase, err = filepath.Abs(srcRoot)
+		if err != nil {
+			return err
+		}
+	}
+
+	return filepath.Walk(srcRoot, func(srcPath string, info os.FileInfo, err error) error {
+		if err != nil || srcPath == srcRoot {
+			return err
+		}
+
+		suffix := strings.TrimPrefix(srcPath, srcRoot)
+		for len(suffix) > 0 && suffix[0] == filepath.Separator {
+			suffix = suffix[1:]
+		}
+		dstPath := filepath.Join(dstRoot, suffix)
+
+		perm := info.Mode() & os.ModePerm
+		if info.Mode()&os.ModeSymlink != 0 {
+			info, err = os.Stat(srcPath)
+			if err != nil {
+				return err
+			}
+			perm = info.Mode() & os.ModePerm
+		}
+
+		// Always copy directories (don't symlink them).
+		// If we add a file in the overlay, we don't want to add it in the original.
+		if info.IsDir() {
+			return os.Mkdir(dstPath, perm)
+		}
+
+		// If the OS supports symlinks, use them instead of copying bytes.
+		if err := os.Symlink(filepath.Join(symBase, suffix), dstPath); err == nil {
+			return nil
+		}
+
+		// Otherwise, copy the bytes.
+		src, err := os.Open(srcPath)
+		if err != nil {
+			return err
+		}
+		defer src.Close()
+
+		dst, err := os.OpenFile(dstPath, os.O_WRONLY|os.O_CREATE|os.O_EXCL, perm)
+		if err != nil {
+			return err
+		}
+
+		_, err = io.Copy(dst, src)
+		if closeErr := dst.Close(); err == nil {
+			err = closeErr
+		}
+		return err
+	})
+}
diff --git a/libgo/misc/cgo/life/c-life.c b/libgo/misc/cgo/life/testdata/c-life.c
index f853163e2f0..f853163e2f0 100644
--- a/libgo/misc/cgo/life/c-life.c
+++ b/libgo/misc/cgo/life/testdata/c-life.c
diff --git a/libgo/misc/cgo/life/life.go b/libgo/misc/cgo/life/testdata/life.go
index 170a620c878..2e0af81d05f 100644
--- a/libgo/misc/cgo/life/life.go
+++ b/libgo/misc/cgo/life/testdata/life.go
@@ -4,7 +4,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package life
+package cgolife
 
 // #include "life.h"
 import "C"
diff --git a/libgo/misc/cgo/life/life.h b/libgo/misc/cgo/life/testdata/life.h
index 11d2b972267..11d2b972267 100644
--- a/libgo/misc/cgo/life/life.h
+++ b/libgo/misc/cgo/life/testdata/life.h
diff --git a/libgo/misc/cgo/life/main.go b/libgo/misc/cgo/life/testdata/main.go
index 145a273bdd1..cc2ca7c7423 100644
--- a/libgo/misc/cgo/life/main.go
+++ b/libgo/misc/cgo/life/testdata/main.go
@@ -14,7 +14,7 @@ import (
 	"flag"
 	"fmt"
 
-	"."
+	"cgolife"
 )
 
 const MAXDIM = 100
@@ -34,7 +34,7 @@ func main() {
 		}
 	}
 
-	life.Run(*gen, *dim, *dim, a[:])
+	cgolife.Run(*gen, *dim, *dim, a[:])
 
 	for i := 0; i < *dim; i++ {
 		for j := 0; j < *dim; j++ {
diff --git a/libgo/misc/cgo/life/main.out b/libgo/misc/cgo/life/testdata/main.out
index 26fc9c6e3ff..26fc9c6e3ff 100644
--- a/libgo/misc/cgo/life/main.out
+++ b/libgo/misc/cgo/life/testdata/main.out
diff --git a/libgo/misc/cgo/stdio/overlaydir_test.go b/libgo/misc/cgo/stdio/overlaydir_test.go
new file mode 100644
index 00000000000..8a8dcdb3a5a
--- /dev/null
+++ b/libgo/misc/cgo/stdio/overlaydir_test.go
@@ -0,0 +1,81 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package stdio_test
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// overlayDir makes a minimal-overhead copy of srcRoot in which new files may be added.
+//
+// TODO: Once we no longer need to support the misc module in GOPATH mode,
+// factor this function out into a package to reduce duplication.
+func overlayDir(dstRoot, srcRoot string) error {
+	dstRoot = filepath.Clean(dstRoot)
+	if err := os.MkdirAll(dstRoot, 0777); err != nil {
+		return err
+	}
+
+	symBase, err := filepath.Rel(srcRoot, dstRoot)
+	if err != nil {
+		symBase, err = filepath.Abs(srcRoot)
+		if err != nil {
+			return err
+		}
+	}
+
+	return filepath.Walk(srcRoot, func(srcPath string, info os.FileInfo, err error) error {
+		if err != nil || srcPath == srcRoot {
+			return err
+		}
+
+		suffix := strings.TrimPrefix(srcPath, srcRoot)
+		for len(suffix) > 0 && suffix[0] == filepath.Separator {
+			suffix = suffix[1:]
+		}
+		dstPath := filepath.Join(dstRoot, suffix)
+
+		perm := info.Mode() & os.ModePerm
+		if info.Mode()&os.ModeSymlink != 0 {
+			info, err = os.Stat(srcPath)
+			if err != nil {
+				return err
+			}
+			perm = info.Mode() & os.ModePerm
+		}
+
+		// Always copy directories (don't symlink them).
+		// If we add a file in the overlay, we don't want to add it in the original.
+		if info.IsDir() {
+			return os.Mkdir(dstPath, perm)
+		}
+
+		// If the OS supports symlinks, use them instead of copying bytes.
+		if err := os.Symlink(filepath.Join(symBase, suffix), dstPath); err == nil {
+			return nil
+		}
+
+		// Otherwise, copy the bytes.
+		src, err := os.Open(srcPath)
+		if err != nil {
+			return err
+		}
+		defer src.Close()
+
+		dst, err := os.OpenFile(dstPath, os.O_WRONLY|os.O_CREATE|os.O_EXCL, perm)
+		if err != nil {
+			return err
+		}
+
+		_, err = io.Copy(dst, src)
+		if closeErr := dst.Close(); err == nil {
+			err = closeErr
+		}
+		return err
+	})
+}
diff --git a/libgo/misc/cgo/stdio/stdio_test.go b/libgo/misc/cgo/stdio/stdio_test.go
new file mode 100644
index 00000000000..ab5d328f676
--- /dev/null
+++ b/libgo/misc/cgo/stdio/stdio_test.go
@@ -0,0 +1,64 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package stdio_test
+
+import (
+	"bytes"
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestMain(m *testing.M) {
+	log.SetFlags(log.Lshortfile)
+	os.Exit(testMain(m))
+}
+
+func testMain(m *testing.M) int {
+	GOPATH, err := ioutil.TempDir("", "cgostdio")
+	if err != nil {
+		log.Panic(err)
+	}
+	defer os.RemoveAll(GOPATH)
+	os.Setenv("GOPATH", GOPATH)
+
+	// Copy testdata into GOPATH/src/cgostdio, along with a go.mod file
+	// declaring the same path.
+	modRoot := filepath.Join(GOPATH, "src", "cgostdio")
+	if err := overlayDir(modRoot, "testdata"); err != nil {
+		log.Panic(err)
+	}
+	if err := os.Chdir(modRoot); err != nil {
+		log.Panic(err)
+	}
+	os.Setenv("PWD", modRoot)
+	if err := ioutil.WriteFile("go.mod", []byte("module cgostdio\n"), 0666); err != nil {
+		log.Panic(err)
+	}
+
+	return m.Run()
+}
+
+func TestTestRun(t *testing.T) {
+	if os.Getenv("GOOS") == "android" {
+		t.Skip("subpackage stdio is not available on android")
+	}
+	out, err := exec.Command("go", "env", "GOROOT").Output()
+	if err != nil {
+		t.Fatal(err)
+	}
+	GOROOT := string(bytes.TrimSpace(out))
+
+	cmd := exec.Command("go", "run", filepath.Join(GOROOT, "test", "run.go"), "-", ".")
+	out, err = cmd.CombinedOutput()
+	if err != nil {
+		t.Fatalf("%s: %s\n%s", strings.Join(cmd.Args, " "), err, out)
+	}
+	t.Logf("%s:\n%s", strings.Join(cmd.Args, " "), out)
+}
diff --git a/libgo/misc/cgo/stdio/chain.go b/libgo/misc/cgo/stdio/testdata/chain.go
index cdc385208c9..6c3f406a0da 100644
--- a/libgo/misc/cgo/stdio/chain.go
+++ b/libgo/misc/cgo/stdio/testdata/chain.go
@@ -14,7 +14,7 @@ import (
 	"runtime"
 	"strconv"
 
-	"../stdio"
+	"cgostdio/stdio"
 )
 
 const N = 10
diff --git a/libgo/misc/cgo/stdio/chain.out b/libgo/misc/cgo/stdio/testdata/chain.out
index 963cf9b6679..963cf9b6679 100644
--- a/libgo/misc/cgo/stdio/chain.out
+++ b/libgo/misc/cgo/stdio/testdata/chain.out
diff --git a/libgo/misc/cgo/stdio/fib.go b/libgo/misc/cgo/stdio/testdata/fib.go
index 58f185c90f0..49cb0ea06f2 100644
--- a/libgo/misc/cgo/stdio/fib.go
+++ b/libgo/misc/cgo/stdio/testdata/fib.go
@@ -17,7 +17,7 @@ import (
 	"runtime"
 	"strconv"
 
-	"../stdio"
+	"cgostdio/stdio"
 )
 
 func fibber(c, out chan int64, i int64) {
diff --git a/libgo/misc/cgo/stdio/fib.out b/libgo/misc/cgo/stdio/testdata/fib.out
index 17ff503356d..17ff503356d 100644
--- a/libgo/misc/cgo/stdio/fib.out
+++ b/libgo/misc/cgo/stdio/testdata/fib.out
diff --git a/libgo/misc/cgo/stdio/hello.go b/libgo/misc/cgo/stdio/testdata/hello.go
index 56220d34be3..046bfee7a79 100644
--- a/libgo/misc/cgo/stdio/hello.go
+++ b/libgo/misc/cgo/stdio/testdata/hello.go
@@ -8,7 +8,7 @@
 
 package main
 
-import "../stdio"
+import "cgostdio/stdio"
 
 func main() {
 	stdio.Stdout.WriteString(stdio.Greeting + "\n")
diff --git a/libgo/misc/cgo/stdio/hello.out b/libgo/misc/cgo/stdio/testdata/hello.out
index 4b5fa63702d..4b5fa63702d 100644
--- a/libgo/misc/cgo/stdio/hello.out
+++ b/libgo/misc/cgo/stdio/testdata/hello.out
diff --git a/libgo/misc/cgo/stdio/run.out b/libgo/misc/cgo/stdio/testdata/run.out
index c0e496547ed..c0e496547ed 100644
--- a/libgo/misc/cgo/stdio/run.out
+++ b/libgo/misc/cgo/stdio/testdata/run.out
diff --git a/libgo/misc/cgo/stdio/file.go b/libgo/misc/cgo/stdio/testdata/stdio/file.go
index a024f2c361c..a024f2c361c 100644
--- a/libgo/misc/cgo/stdio/file.go
+++ b/libgo/misc/cgo/stdio/testdata/stdio/file.go
diff --git a/libgo/misc/cgo/stdio/stdio.go b/libgo/misc/cgo/stdio/testdata/stdio/stdio.go
index d216e44fe7c..d216e44fe7c 100644
--- a/libgo/misc/cgo/stdio/stdio.go
+++ b/libgo/misc/cgo/stdio/testdata/stdio/stdio.go
diff --git a/libgo/misc/cgo/test/align.go b/libgo/misc/cgo/test/align.go
deleted file mode 100644
index a23b44fc38c..00000000000
--- a/libgo/misc/cgo/test/align.go
+++ /dev/null
@@ -1,76 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-#include <stdio.h>
-
-typedef unsigned char Uint8;
-typedef unsigned short Uint16;
-
-typedef enum {
- MOD1 = 0x0000,
- MODX = 0x8000
-} SDLMod;
-
-typedef enum {
- A = 1,
- B = 322,
- SDLK_LAST
-} SDLKey;
-
-typedef struct SDL_keysym {
-	Uint8 scancode;
-	SDLKey sym;
-	SDLMod mod;
-	Uint16 unicode;
-} SDL_keysym;
-
-typedef struct SDL_KeyboardEvent {
-	Uint8 typ;
-	Uint8 which;
-	Uint8 state;
-	SDL_keysym keysym;
-} SDL_KeyboardEvent;
-
-void makeEvent(SDL_KeyboardEvent *event) {
- unsigned char *p;
- int i;
-
- p = (unsigned char*)event;
- for (i=0; i<sizeof *event; i++) {
-   p[i] = i;
- }
-}
-
-int same(SDL_KeyboardEvent* e, Uint8 typ, Uint8 which, Uint8 state, Uint8 scan, SDLKey sym, SDLMod mod, Uint16 uni) {
-  return e->typ == typ && e->which == which && e->state == state && e->keysym.scancode == scan && e->keysym.sym == sym && e->keysym.mod == mod && e->keysym.unicode == uni;
-}
-
-void cTest(SDL_KeyboardEvent *event) {
- printf("C: %#x %#x %#x %#x %#x %#x %#x\n", event->typ, event->which, event->state,
-   event->keysym.scancode, event->keysym.sym, event->keysym.mod, event->keysym.unicode);
- fflush(stdout);
-}
-
-*/
-import "C"
-
-import (
-	"testing"
-)
-
-func testAlign(t *testing.T) {
-	var evt C.SDL_KeyboardEvent
-	C.makeEvent(&evt)
-	if C.same(&evt, evt.typ, evt.which, evt.state, evt.keysym.scancode, evt.keysym.sym, evt.keysym.mod, evt.keysym.unicode) == 0 {
-		t.Error("*** bad alignment")
-		C.cTest(&evt)
-		t.Errorf("Go: %#x %#x %#x %#x %#x %#x %#x\n",
-			evt.typ, evt.which, evt.state, evt.keysym.scancode,
-			evt.keysym.sym, evt.keysym.mod, evt.keysym.unicode)
-		t.Error(evt)
-	}
-}
diff --git a/libgo/misc/cgo/test/api.go b/libgo/misc/cgo/test/api.go
deleted file mode 100644
index d2b09cbeffe..00000000000
--- a/libgo/misc/cgo/test/api.go
+++ /dev/null
@@ -1,30 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// API Compatibility Checks for cgo
-
-package cgotest
-
-// #include <stdlib.h>
-//
-// // Test for issue 17723.
-// typedef char *cstring_pointer;
-// static void cstring_pointer_fun(cstring_pointer dummy) { }
-//
-// const char *api_hello = "hello!";
-import "C"
-import "unsafe"
-
-func testAPI() {
-	var cs *C.char
-	cs = C.CString("hello")
-	defer C.free(unsafe.Pointer(cs))
-	var s string
-	s = C.GoString((*C.char)(C.api_hello))
-	s = C.GoStringN((*C.char)(C.api_hello), C.int(6))
-	var b []byte
-	b = C.GoBytes(unsafe.Pointer(C.api_hello), C.int(6))
-	_, _ = s, b
-	C.cstring_pointer_fun(nil)
-}
diff --git a/libgo/misc/cgo/test/basic.go b/libgo/misc/cgo/test/basic.go
deleted file mode 100644
index 2655a66e381..00000000000
--- a/libgo/misc/cgo/test/basic.go
+++ /dev/null
@@ -1,181 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Basic test cases for cgo.
-
-package cgotest
-
-/*
-#include <stdio.h>
-#include <stdlib.h>
-#include <sys/stat.h>
-#include <errno.h>
-
-#define SHIFT(x, y)  ((x)<<(y))
-#define KILO SHIFT(1, 10)
-#define UINT32VAL 0xc008427bU
-
-enum E {
-	Enum1 = 1,
-	Enum2 = 2,
-};
-
-typedef unsigned char cgo_uuid_t[20];
-
-void uuid_generate(cgo_uuid_t x) {
-	x[0] = 0;
-}
-
-struct S {
-	int x;
-};
-
-const char *cstr = "abcefghijklmnopqrstuvwxyzABCEFGHIJKLMNOPQRSTUVWXYZ1234567890";
-
-extern enum E myConstFunc(struct S* const ctx, int const id, struct S **const filter);
-
-enum E myConstFunc(struct S *const ctx, int const id, struct S **const filter) { return 0; }
-
-// issue 1222
-typedef union {
-	long align;
-} xxpthread_mutex_t;
-
-struct ibv_async_event {
-	union {
-		int x;
-	} element;
-};
-
-struct ibv_context {
-	xxpthread_mutex_t mutex;
-};
-
-int add(int x, int y) {
-	return x+y;
-};
-*/
-import "C"
-import (
-	"runtime"
-	"syscall"
-	"testing"
-	"unsafe"
-)
-
-const EINVAL = C.EINVAL /* test #define */
-
-var KILO = C.KILO
-
-func uuidgen() {
-	var uuid C.cgo_uuid_t
-	C.uuid_generate(&uuid[0])
-}
-
-func Strtol(s string, base int) (int, error) {
-	p := C.CString(s)
-	n, err := C.strtol(p, nil, C.int(base))
-	C.free(unsafe.Pointer(p))
-	return int(n), err
-}
-
-func Atol(s string) int {
-	p := C.CString(s)
-	n := C.atol(p)
-	C.free(unsafe.Pointer(p))
-	return int(n)
-}
-
-func testConst(t *testing.T) {
-	C.myConstFunc(nil, 0, nil)
-}
-
-func testEnum(t *testing.T) {
-	if C.Enum1 != 1 || C.Enum2 != 2 {
-		t.Error("bad enum", C.Enum1, C.Enum2)
-	}
-}
-
-func testAtol(t *testing.T) {
-	l := Atol("123")
-	if l != 123 {
-		t.Error("Atol 123: ", l)
-	}
-}
-
-func testErrno(t *testing.T) {
-	p := C.CString("no-such-file")
-	m := C.CString("r")
-	f, err := C.fopen(p, m)
-	C.free(unsafe.Pointer(p))
-	C.free(unsafe.Pointer(m))
-	if err == nil {
-		C.fclose(f)
-		t.Fatalf("C.fopen: should fail")
-	}
-	if err != syscall.ENOENT {
-		t.Fatalf("C.fopen: unexpected error: %v", err)
-	}
-}
-
-func testMultipleAssign(t *testing.T) {
-	p := C.CString("234")
-	n, m := C.strtol(p, nil, 345), C.strtol(p, nil, 10)
-	if runtime.GOOS == "openbsd" {
-		// Bug in OpenBSD strtol(3) - base > 36 succeeds.
-		if (n != 0 && n != 239089) || m != 234 {
-			t.Fatal("Strtol x2: ", n, m)
-		}
-	} else if n != 0 || m != 234 {
-		t.Fatal("Strtol x2: ", n, m)
-	}
-	C.free(unsafe.Pointer(p))
-}
-
-var (
-	cuint  = (C.uint)(0)
-	culong C.ulong
-	cchar  C.char
-)
-
-type Context struct {
-	ctx *C.struct_ibv_context
-}
-
-func benchCgoCall(b *testing.B) {
-	const x = C.int(2)
-	const y = C.int(3)
-	for i := 0; i < b.N; i++ {
-		C.add(x, y)
-	}
-}
-
-var sinkString string
-
-func benchGoString(b *testing.B) {
-	for i := 0; i < b.N; i++ {
-		sinkString = C.GoString(C.cstr)
-	}
-	const want = "abcefghijklmnopqrstuvwxyzABCEFGHIJKLMNOPQRSTUVWXYZ1234567890"
-	if sinkString != want {
-		b.Fatalf("%q != %q", sinkString, want)
-	}
-}
-
-// Issue 2470.
-func testUnsignedInt(t *testing.T) {
-	a := (int64)(C.UINT32VAL)
-	b := (int64)(0xc008427b)
-	if a != b {
-		t.Errorf("Incorrect unsigned int - got %x, want %x", a, b)
-	}
-}
-
-// Static (build-time) test that syntax traversal visits all operands of s[i:j:k].
-func sliceOperands(array [2000]int) {
-	_ = array[C.KILO:C.KILO:C.KILO] // no type error
-}
-
-// set in cgo_thread_lock.go init
-var testThreadLockFunc = func(*testing.T) {}
diff --git a/libgo/misc/cgo/test/callback.go b/libgo/misc/cgo/test/callback.go
index 4fc6b39ffa6..e7496502931 100644
--- a/libgo/misc/cgo/test/callback.go
+++ b/libgo/misc/cgo/test/callback.go
@@ -199,7 +199,7 @@ func testCallbackCallers(t *testing.T) {
 		t.Errorf("expected %d frames, got %d", len(name), n)
 	}
 	for i := 0; i < n; i++ {
-		f := runtime.FuncForPC(pc[i])
+		f := runtime.FuncForPC(pc[i] - 1) // TODO: use runtime.CallersFrames
 		if f == nil {
 			t.Fatalf("expected non-nil Func for pc %d", pc[i])
 		}
@@ -209,6 +209,10 @@ func testCallbackCallers(t *testing.T) {
 		if strings.HasPrefix(fname, "_") {
 			fname = path.Base(f.Name()[1:])
 		}
+		// In module mode, this package has a fully-qualified import path.
+		// Remove it if present.
+		fname = strings.TrimPrefix(fname, "misc/cgo/")
+
 		namei := ""
 		if i < len(name) {
 			namei = name[i]
diff --git a/libgo/misc/cgo/test/cflags.go b/libgo/misc/cgo/test/cflags.go
deleted file mode 100644
index bc290bfcd5a..00000000000
--- a/libgo/misc/cgo/test/cflags.go
+++ /dev/null
@@ -1,32 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Test that the #cgo CFLAGS directive works,
-// with and without platform filters.
-// See https://golang.org/issue/5224 for details.
-package cgotest
-
-/*
-#cgo CFLAGS: -DCOMMON_VALUE=123
-#cgo windows CFLAGS: -DIS_WINDOWS=1
-#cgo !windows CFLAGS: -DIS_WINDOWS=0
-int common = COMMON_VALUE;
-int is_windows = IS_WINDOWS;
-*/
-import "C"
-
-import (
-	"runtime"
-	"testing"
-)
-
-func testCflags(t *testing.T) {
-	is_windows := C.is_windows == 1
-	if is_windows != (runtime.GOOS == "windows") {
-		t.Errorf("is_windows: %v, runtime.GOOS: %s", is_windows, runtime.GOOS)
-	}
-	if C.common != 123 {
-		t.Errorf("common: %v (expected 123)", C.common)
-	}
-}
diff --git a/libgo/misc/cgo/test/cgo_linux_test.go b/libgo/misc/cgo/test/cgo_linux_test.go
index 9c15f69e401..7b56e11a27d 100644
--- a/libgo/misc/cgo/test/cgo_linux_test.go
+++ b/libgo/misc/cgo/test/cgo_linux_test.go
@@ -4,9 +4,16 @@
 
 package cgotest
 
-import "testing"
+import (
+	"runtime"
+	"testing"
+)
 
-func TestSetgid(t *testing.T)  { testSetgid(t) }
+func TestSetgid(t *testing.T) {
+	if runtime.GOOS == "android" {
+		t.Skip("unsupported on Android")
+	}
+	testSetgid(t)
+}
 func Test6997(t *testing.T)    { test6997(t) }
 func TestBuildID(t *testing.T) { testBuildID(t) }
-func Test9400(t *testing.T)    { test9400(t) }
diff --git a/libgo/misc/cgo/test/cgo_stubs_android_test.go b/libgo/misc/cgo/test/cgo_stubs_android_test.go
index 710e094cf77..a1c2482ab8d 100644
--- a/libgo/misc/cgo/test/cgo_stubs_android_test.go
+++ b/libgo/misc/cgo/test/cgo_stubs_android_test.go
@@ -8,6 +8,5 @@ import "testing"
 
 // Stubs for tests that fails to build on Android
 func test6997(t *testing.T)        {}
-func test3775(t *testing.T)        {}
 func test8694(t *testing.T)        {}
 func testSigaltstack(t *testing.T) {}
diff --git a/libgo/misc/cgo/test/cgo_test.go b/libgo/misc/cgo/test/cgo_test.go
index 2cb93d9c2eb..c66df2cd461 100644
--- a/libgo/misc/cgo/test/cgo_test.go
+++ b/libgo/misc/cgo/test/cgo_test.go
@@ -10,91 +10,86 @@ import "testing"
 // so that they can use cgo (import "C").
 // These wrappers are here for gotest to find.
 
-func TestAlign(t *testing.T)                 { testAlign(t) }
-func TestConst(t *testing.T)                 { testConst(t) }
-func TestEnum(t *testing.T)                  { testEnum(t) }
-func TestAtol(t *testing.T)                  { testAtol(t) }
-func TestErrno(t *testing.T)                 { testErrno(t) }
-func TestMultipleAssign(t *testing.T)        { testMultipleAssign(t) }
-func TestUnsignedInt(t *testing.T)           { testUnsignedInt(t) }
-func TestCallback(t *testing.T)              { testCallback(t) }
-func TestCallbackGC(t *testing.T)            { testCallbackGC(t) }
-func TestCallbackPanic(t *testing.T)         { testCallbackPanic(t) }
-func TestCallbackPanicLoop(t *testing.T)     { testCallbackPanicLoop(t) }
-func TestCallbackPanicLocked(t *testing.T)   { testCallbackPanicLocked(t) }
-func TestPanicFromC(t *testing.T)            { testPanicFromC(t) }
-func TestZeroArgCallback(t *testing.T)       { testZeroArgCallback(t) }
-func TestBlocking(t *testing.T)              { testBlocking(t) }
 func Test1328(t *testing.T)                  { test1328(t) }
-func TestParallelSleep(t *testing.T)         { testParallelSleep(t) }
-func TestSetEnv(t *testing.T)                { testSetEnv(t) }
-func TestHelpers(t *testing.T)               { testHelpers(t) }
-func TestLibgcc(t *testing.T)                { testLibgcc(t) }
 func Test1635(t *testing.T)                  { test1635(t) }
-func TestPrintf(t *testing.T)                { testPrintf(t) }
-func Test4029(t *testing.T)                  { test4029(t) }
-func TestBoolAlign(t *testing.T)             { testBoolAlign(t) }
+func Test3250(t *testing.T)                  { test3250(t) }
 func Test3729(t *testing.T)                  { test3729(t) }
 func Test3775(t *testing.T)                  { test3775(t) }
-func TestCthread(t *testing.T)               { testCthread(t) }
-func TestCallbackCallers(t *testing.T)       { testCallbackCallers(t) }
+func Test4029(t *testing.T)                  { test4029(t) }
+func Test4339(t *testing.T)                  { test4339(t) }
 func Test5227(t *testing.T)                  { test5227(t) }
-func TestCflags(t *testing.T)                { testCflags(t) }
+func Test5242(t *testing.T)                  { test5242(t) }
 func Test5337(t *testing.T)                  { test5337(t) }
 func Test5548(t *testing.T)                  { test5548(t) }
 func Test5603(t *testing.T)                  { test5603(t) }
-func Test6833(t *testing.T)                  { test6833(t) }
-func Test3250(t *testing.T)                  { test3250(t) }
-func TestCallbackStack(t *testing.T)         { testCallbackStack(t) }
-func TestFpVar(t *testing.T)                 { testFpVar(t) }
-func Test4339(t *testing.T)                  { test4339(t) }
-func Test6390(t *testing.T)                  { test6390(t) }
 func Test5986(t *testing.T)                  { test5986(t) }
-func Test7665(t *testing.T)                  { test7665(t) }
-func TestNaming(t *testing.T)                { testNaming(t) }
+func Test6390(t *testing.T)                  { test6390(t) }
+func Test6833(t *testing.T)                  { test6833(t) }
+func Test6907(t *testing.T)                  { test6907(t) }
+func Test6907Go(t *testing.T)                { test6907Go(t) }
 func Test7560(t *testing.T)                  { test7560(t) }
-func Test5242(t *testing.T)                  { test5242(t) }
-func Test8092(t *testing.T)                  { test8092(t) }
+func Test7665(t *testing.T)                  { test7665(t) }
 func Test7978(t *testing.T)                  { test7978(t) }
-func Test8694(t *testing.T)                  { test8694(t) }
+func Test8092(t *testing.T)                  { test8092(t) }
 func Test8517(t *testing.T)                  { test8517(t) }
+func Test8694(t *testing.T)                  { test8694(t) }
 func Test8811(t *testing.T)                  { test8811(t) }
-func TestReturnAfterGrow(t *testing.T)       { testReturnAfterGrow(t) }
-func TestReturnAfterGrowFromGo(t *testing.T) { testReturnAfterGrowFromGo(t) }
-func Test9026(t *testing.T)                  { test9026(t) }
-func Test9510(t *testing.T)                  { test9510(t) }
 func Test9557(t *testing.T)                  { test9557(t) }
 func Test10303(t *testing.T)                 { test10303(t, 10) }
 func Test11925(t *testing.T)                 { test11925(t) }
 func Test12030(t *testing.T)                 { test12030(t) }
-func TestGCC68255(t *testing.T)              { testGCC68255(t) }
-func TestCallGoWithString(t *testing.T)      { testCallGoWithString(t) }
 func Test14838(t *testing.T)                 { test14838(t) }
-func Test8756(t *testing.T)                  { test8756(t) }
 func Test17065(t *testing.T)                 { test17065(t) }
-func TestThreadLock(t *testing.T)            { testThreadLockFunc(t) }
-func TestCheckConst(t *testing.T)            { testCheckConst(t) }
 func Test17537(t *testing.T)                 { test17537(t) }
 func Test18126(t *testing.T)                 { test18126(t) }
-func Test20369(t *testing.T)                 { test20369(t) }
 func Test18720(t *testing.T)                 { test18720(t) }
-func Test20266(t *testing.T)                 { test20266(t) }
 func Test20129(t *testing.T)                 { test20129(t) }
+func Test20369(t *testing.T)                 { test20369(t) }
 func Test20910(t *testing.T)                 { test20910(t) }
 func Test21708(t *testing.T)                 { test21708(t) }
 func Test21809(t *testing.T)                 { test21809(t) }
-func Test6907(t *testing.T)                  { test6907(t) }
-func Test6907Go(t *testing.T)                { test6907Go(t) }
 func Test21897(t *testing.T)                 { test21897(t) }
 func Test22906(t *testing.T)                 { test22906(t) }
+func Test23356(t *testing.T)                 { test23356(t) }
 func Test24206(t *testing.T)                 { test24206(t) }
 func Test25143(t *testing.T)                 { test25143(t) }
-func Test23356(t *testing.T)                 { test23356(t) }
 func Test26066(t *testing.T)                 { test26066(t) }
-func Test26213(t *testing.T)                 { test26213(t) }
 func Test27660(t *testing.T)                 { test27660(t) }
 func Test28896(t *testing.T)                 { test28896(t) }
 func Test30065(t *testing.T)                 { test30065(t) }
+func Test32579(t *testing.T)                 { test32579(t) }
+func TestAlign(t *testing.T)                 { testAlign(t) }
+func TestAtol(t *testing.T)                  { testAtol(t) }
+func TestBlocking(t *testing.T)              { testBlocking(t) }
+func TestBoolAlign(t *testing.T)             { testBoolAlign(t) }
+func TestCallGoWithString(t *testing.T)      { testCallGoWithString(t) }
+func TestCallback(t *testing.T)              { testCallback(t) }
+func TestCallbackCallers(t *testing.T)       { testCallbackCallers(t) }
+func TestCallbackGC(t *testing.T)            { testCallbackGC(t) }
+func TestCallbackPanic(t *testing.T)         { testCallbackPanic(t) }
+func TestCallbackPanicLocked(t *testing.T)   { testCallbackPanicLocked(t) }
+func TestCallbackPanicLoop(t *testing.T)     { testCallbackPanicLoop(t) }
+func TestCallbackStack(t *testing.T)         { testCallbackStack(t) }
+func TestCflags(t *testing.T)                { testCflags(t) }
+func TestCheckConst(t *testing.T)            { testCheckConst(t) }
+func TestConst(t *testing.T)                 { testConst(t) }
+func TestCthread(t *testing.T)               { testCthread(t) }
+func TestEnum(t *testing.T)                  { testEnum(t) }
+func TestErrno(t *testing.T)                 { testErrno(t) }
+func TestFpVar(t *testing.T)                 { testFpVar(t) }
+func TestHelpers(t *testing.T)               { testHelpers(t) }
+func TestLibgcc(t *testing.T)                { testLibgcc(t) }
+func TestMultipleAssign(t *testing.T)        { testMultipleAssign(t) }
+func TestNaming(t *testing.T)                { testNaming(t) }
+func TestPanicFromC(t *testing.T)            { testPanicFromC(t) }
+func TestParallelSleep(t *testing.T)         { testParallelSleep(t) }
+func TestPrintf(t *testing.T)                { testPrintf(t) }
+func TestReturnAfterGrow(t *testing.T)       { testReturnAfterGrow(t) }
+func TestReturnAfterGrowFromGo(t *testing.T) { testReturnAfterGrowFromGo(t) }
+func TestSetEnv(t *testing.T)                { testSetEnv(t) }
+func TestThreadLock(t *testing.T)            { testThreadLockFunc(t) }
+func TestUnsignedInt(t *testing.T)           { testUnsignedInt(t) }
+func TestZeroArgCallback(t *testing.T)       { testZeroArgCallback(t) }
 
 func BenchmarkCgoCall(b *testing.B)  { benchCgoCall(b) }
 func BenchmarkGoString(b *testing.B) { benchGoString(b) }
diff --git a/libgo/misc/cgo/test/checkconst.go b/libgo/misc/cgo/test/checkconst.go
deleted file mode 100644
index 0160c1e0ced..00000000000
--- a/libgo/misc/cgo/test/checkconst.go
+++ /dev/null
@@ -1,33 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Test a constant in conjunction with pointer checking.
-
-package cgotest
-
-/*
-#include <stdlib.h>
-
-#define CheckConstVal 0
-
-typedef struct {
-	int *p;
-} CheckConstStruct;
-
-static void CheckConstFunc(CheckConstStruct *p, int e) {
-}
-*/
-import "C"
-
-import (
-	"testing"
-	"unsafe"
-)
-
-func testCheckConst(t *testing.T) {
-	// The test is that this compiles successfully.
-	p := C.malloc(C.size_t(unsafe.Sizeof(C.int(0))))
-	defer C.free(p)
-	C.CheckConstFunc(&C.CheckConstStruct{(*C.int)(p)}, C.CheckConstVal)
-}
diff --git a/libgo/misc/cgo/test/complex.go b/libgo/misc/cgo/test/complex.go
deleted file mode 100644
index ca0a97d9b34..00000000000
--- a/libgo/misc/cgo/test/complex.go
+++ /dev/null
@@ -1,24 +0,0 @@
-// Copyright 2016 The Go Authors.  All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-struct {
-	float x;
-	_Complex float y;
-} cplxAlign = { 3.14, 2.17 };
-*/
-import "C"
-
-import "testing"
-
-func TestComplexAlign(t *testing.T) {
-	if C.cplxAlign.x != 3.14 {
-		t.Errorf("got %v, expected 3.14", C.cplxAlign.x)
-	}
-	if C.cplxAlign.y != 2.17 {
-		t.Errorf("got %v, expected 2.17", C.cplxAlign.y)
-	}
-}
diff --git a/libgo/misc/cgo/test/cthread.go b/libgo/misc/cgo/test/cthread.go
deleted file mode 100644
index af44911756a..00000000000
--- a/libgo/misc/cgo/test/cthread.go
+++ /dev/null
@@ -1,44 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-// extern void doAdd(int, int);
-import "C"
-
-import (
-	"runtime"
-	"sync"
-	"testing"
-)
-
-var sum struct {
-	sync.Mutex
-	i int
-}
-
-//export Add
-func Add(x int) {
-	defer func() {
-		recover()
-	}()
-	sum.Lock()
-	sum.i += x
-	sum.Unlock()
-	var p *int
-	*p = 2
-}
-
-func testCthread(t *testing.T) {
-	if runtime.GOOS == "darwin" && (runtime.GOARCH == "arm" || runtime.GOARCH == "arm64") {
-		t.Skip("the iOS exec wrapper is unable to properly handle the panic from Add")
-	}
-	sum.i = 0
-	C.doAdd(10, 6)
-
-	want := 10 * (10 - 1) / 2 * 6
-	if sum.i != want {
-		t.Fatalf("sum=%d, want %d", sum.i, want)
-	}
-}
diff --git a/libgo/misc/cgo/test/duplicate_symbol.go b/libgo/misc/cgo/test/duplicate_symbol.go
deleted file mode 100644
index 61442713215..00000000000
--- a/libgo/misc/cgo/test/duplicate_symbol.go
+++ /dev/null
@@ -1,21 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file contains test cases for cgo.
-
-package cgotest
-
-/*
-int base_symbol = 0;
-
-#define alias_one base_symbol
-#define alias_two base_symbol
-*/
-import "C"
-
-import "fmt"
-
-func duplicateSymbols() {
-	fmt.Printf("%v %v %v\n", C.base_symbol, C.alias_one, C.alias_two)
-}
diff --git a/libgo/misc/cgo/test/env.go b/libgo/misc/cgo/test/env.go
deleted file mode 100644
index b2081b72837..00000000000
--- a/libgo/misc/cgo/test/env.go
+++ /dev/null
@@ -1,41 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-#include <stdlib.h>
-*/
-import "C"
-import (
-	"os"
-	"runtime"
-	"testing"
-	"unsafe"
-)
-
-// This is really an os package test but here for convenience.
-func testSetEnv(t *testing.T) {
-	if runtime.GOOS == "windows" {
-		// Go uses SetEnvironmentVariable on windows. Howerver,
-		// C runtime takes a *copy* at process startup of thei
-		// OS environment, and stores it in environ/envp.
-		// It is this copy that	getenv/putenv manipulate.
-		t.Logf("skipping test")
-		return
-	}
-	const key = "CGO_OS_TEST_KEY"
-	const val = "CGO_OS_TEST_VALUE"
-	os.Setenv(key, val)
-	keyc := C.CString(key)
-	defer C.free(unsafe.Pointer(keyc))
-	v := C.getenv(keyc)
-	if uintptr(unsafe.Pointer(v)) == 0 {
-		t.Fatal("getenv returned NULL")
-	}
-	vs := C.GoString(v)
-	if vs != val {
-		t.Fatalf("getenv() = %q; want %q", vs, val)
-	}
-}
diff --git a/libgo/misc/cgo/test/exports.go b/libgo/misc/cgo/test/exports.go
deleted file mode 100644
index 71e5dcdd3df..00000000000
--- a/libgo/misc/cgo/test/exports.go
+++ /dev/null
@@ -1,18 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-import "C"
-import "runtime"
-
-//export ReturnIntLong
-func ReturnIntLong() (int, C.long) {
-	return 1, 2
-}
-
-//export gc
-func gc() {
-	runtime.GC()
-}
diff --git a/libgo/misc/cgo/test/fpvar.go b/libgo/misc/cgo/test/fpvar.go
deleted file mode 100644
index 7aab8ca2fc2..00000000000
--- a/libgo/misc/cgo/test/fpvar.go
+++ /dev/null
@@ -1,50 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file contains test cases for cgo with function pointer variables.
-
-package cgotest
-
-/*
-typedef int (*intFunc) ();
-
-int
-bridge_int_func(intFunc f)
-{
-	return f();
-}
-
-int fortytwo()
-{
-	return 42;
-}
-
-*/
-import "C"
-import "testing"
-
-func callBridge(f C.intFunc) int {
-	return int(C.bridge_int_func(f))
-}
-
-func callCBridge(f C.intFunc) C.int {
-	return C.bridge_int_func(f)
-}
-
-func testFpVar(t *testing.T) {
-	const expected = 42
-	f := C.intFunc(C.fortytwo)
-	res1 := C.bridge_int_func(f)
-	if r1 := int(res1); r1 != expected {
-		t.Errorf("got %d, want %d", r1, expected)
-	}
-	res2 := callCBridge(f)
-	if r2 := int(res2); r2 != expected {
-		t.Errorf("got %d, want %d", r2, expected)
-	}
-	r3 := callBridge(f)
-	if r3 != expected {
-		t.Errorf("got %d, want %d", r3, expected)
-	}
-}
diff --git a/libgo/misc/cgo/test/helpers.go b/libgo/misc/cgo/test/helpers.go
deleted file mode 100644
index f6a822a1065..00000000000
--- a/libgo/misc/cgo/test/helpers.go
+++ /dev/null
@@ -1,35 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-// const char *greeting = "hello, world";
-import "C"
-
-import (
-	"reflect"
-	"testing"
-	"unsafe"
-)
-
-const greeting = "hello, world"
-
-type testPair struct {
-	Name      string
-	Got, Want interface{}
-}
-
-var testPairs = []testPair{
-	{"GoString", C.GoString(C.greeting), greeting},
-	{"GoStringN", C.GoStringN(C.greeting, 5), greeting[:5]},
-	{"GoBytes", C.GoBytes(unsafe.Pointer(C.greeting), 5), []byte(greeting[:5])},
-}
-
-func testHelpers(t *testing.T) {
-	for _, pair := range testPairs {
-		if !reflect.DeepEqual(pair.Got, pair.Want) {
-			t.Errorf("%s: got %#v, want %#v", pair.Name, pair.Got, pair.Want)
-		}
-	}
-}
diff --git a/libgo/misc/cgo/test/issue10303.go b/libgo/misc/cgo/test/issue10303.go
deleted file mode 100644
index 66e2644d066..00000000000
--- a/libgo/misc/cgo/test/issue10303.go
+++ /dev/null
@@ -1,76 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 10303. Pointers passed to C were not marked as escaping (bug in cgo).
-
-package cgotest
-
-import "runtime"
-
-/*
-typedef int *intptr;
-
-void setintstar(int *x) {
-	*x = 1;
-}
-
-void setintptr(intptr x) {
-	*x = 1;
-}
-
-void setvoidptr(void *x) {
-	*(int*)x = 1;
-}
-
-typedef struct Struct Struct;
-struct Struct {
-	int *P;
-};
-
-void setstruct(Struct s) {
-	*s.P = 1;
-}
-
-*/
-import "C"
-
-import (
-	"testing"
-	"unsafe"
-)
-
-func test10303(t *testing.T, n int) {
-	if runtime.Compiler == "gccgo" {
-		t.Skip("gccgo permits C pointers on the stack")
-	}
-
-	// Run at a few different stack depths just to avoid an unlucky pass
-	// due to variables ending up on different pages.
-	if n > 0 {
-		test10303(t, n-1)
-	}
-	if t.Failed() {
-		return
-	}
-	var x, y, z, v, si C.int
-	var s C.Struct
-	C.setintstar(&x)
-	C.setintptr(&y)
-	C.setvoidptr(unsafe.Pointer(&v))
-	s.P = &si
-	C.setstruct(s)
-
-	if uintptr(unsafe.Pointer(&x))&^0xfff == uintptr(unsafe.Pointer(&z))&^0xfff {
-		t.Error("C int* argument on stack")
-	}
-	if uintptr(unsafe.Pointer(&y))&^0xfff == uintptr(unsafe.Pointer(&z))&^0xfff {
-		t.Error("C intptr argument on stack")
-	}
-	if uintptr(unsafe.Pointer(&v))&^0xfff == uintptr(unsafe.Pointer(&z))&^0xfff {
-		t.Error("C void* argument on stack")
-	}
-	if uintptr(unsafe.Pointer(&si))&^0xfff == uintptr(unsafe.Pointer(&z))&^0xfff {
-		t.Error("C struct field pointer on stack")
-	}
-}
diff --git a/libgo/misc/cgo/test/issue11925.go b/libgo/misc/cgo/test/issue11925.go
deleted file mode 100644
index c5c8a269f79..00000000000
--- a/libgo/misc/cgo/test/issue11925.go
+++ /dev/null
@@ -1,37 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 11925.  Structs with zero-length trailing fields are now
-// padded by the Go compiler.
-
-package cgotest
-
-/*
-struct a11925 {
-	int i;
-	char a[0];
-	char b[0];
-};
-
-struct b11925 {
-	int i;
-	char a[0];
-	char b[];
-};
-*/
-import "C"
-
-import (
-	"testing"
-	"unsafe"
-)
-
-func test11925(t *testing.T) {
-	if C.sizeof_struct_a11925 != unsafe.Sizeof(C.struct_a11925{}) {
-		t.Errorf("size of a changed: C %d, Go %d", C.sizeof_struct_a11925, unsafe.Sizeof(C.struct_a11925{}))
-	}
-	if C.sizeof_struct_b11925 != unsafe.Sizeof(C.struct_b11925{}) {
-		t.Errorf("size of b changed: C %d, Go %d", C.sizeof_struct_b11925, unsafe.Sizeof(C.struct_b11925{}))
-	}
-}
diff --git a/libgo/misc/cgo/test/issue12030.go b/libgo/misc/cgo/test/issue12030.go
deleted file mode 100644
index f863c58aa2a..00000000000
--- a/libgo/misc/cgo/test/issue12030.go
+++ /dev/null
@@ -1,35 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 12030. sprintf is defined in both ntdll and msvcrt,
-// Normally we want the one in the msvcrt.
-
-package cgotest
-
-/*
-#include <stdio.h>
-#include <stdlib.h>
-void issue12030conv(char *buf, double x) {
-	sprintf(buf, "d=%g", x);
-}
-*/
-import "C"
-
-import (
-	"fmt"
-	"testing"
-	"unsafe"
-)
-
-func test12030(t *testing.T) {
-	buf := (*C.char)(C.malloc(256))
-	defer C.free(unsafe.Pointer(buf))
-	for _, f := range []float64{1.0, 2.0, 3.14} {
-		C.issue12030conv(buf, C.double(f))
-		got := C.GoString(buf)
-		if want := fmt.Sprintf("d=%g", f); got != want {
-			t.Fatalf("C.sprintf failed for %g: %q != %q", f, got, want)
-		}
-	}
-}
diff --git a/libgo/misc/cgo/test/issue1222.go b/libgo/misc/cgo/test/issue1222.go
deleted file mode 100644
index 4868da8e185..00000000000
--- a/libgo/misc/cgo/test/issue1222.go
+++ /dev/null
@@ -1,29 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This file contains test cases for cgo.
-
-package cgotest
-
-/*
-// issue 1222
-typedef union {
-	long align;
-} xxpthread_mutex_t;
-
-struct ibv_async_event {
-	union {
-		int x;
-	} element;
-};
-
-struct ibv_context {
-	xxpthread_mutex_t mutex;
-};
-*/
-import "C"
-
-type AsyncEvent struct {
-	event C.struct_ibv_async_event
-}
diff --git a/libgo/misc/cgo/test/issue1328.go b/libgo/misc/cgo/test/issue1328.go
deleted file mode 100644
index 2401c10e300..00000000000
--- a/libgo/misc/cgo/test/issue1328.go
+++ /dev/null
@@ -1,30 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-import "testing"
-
-// extern void BackIntoGo(void);
-// void IntoC(void);
-import "C"
-
-//export BackIntoGo
-func BackIntoGo() {
-	x := 1
-
-	for i := 0; i < 10000; i++ {
-		xvariadic(x)
-		if x != 1 {
-			panic("x is not 1?")
-		}
-	}
-}
-
-func xvariadic(x ...interface{}) {
-}
-
-func test1328(t *testing.T) {
-	C.IntoC()
-}
diff --git a/libgo/misc/cgo/test/issue13930.go b/libgo/misc/cgo/test/issue13930.go
deleted file mode 100644
index c4a08ee7c9e..00000000000
--- a/libgo/misc/cgo/test/issue13930.go
+++ /dev/null
@@ -1,13 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 13930.  Test that cgo's multiple-value special form for
-// C function calls works in variable declaration statements.
-
-package cgotest
-
-// #include <stdlib.h>
-import "C"
-
-var _, _ = C.abs(0)
diff --git a/libgo/misc/cgo/test/issue14838.go b/libgo/misc/cgo/test/issue14838.go
deleted file mode 100644
index c8e1681295e..00000000000
--- a/libgo/misc/cgo/test/issue14838.go
+++ /dev/null
@@ -1,37 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 14838. add CBytes function
-
-package cgotest
-
-/*
-#include <stdlib.h>
-
-int check_cbytes(char *b, size_t l) {
-	int i;
-	for (i = 0; i < l; i++) {
-		if (b[i] != i) {
-			return 0;
-		}
-	}
-	return 1;
-}
-*/
-import "C"
-
-import (
-	"testing"
-	"unsafe"
-)
-
-func test14838(t *testing.T) {
-	data := []byte{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
-	cData := C.CBytes(data)
-	defer C.free(cData)
-
-	if C.check_cbytes((*C.char)(cData), C.size_t(len(data))) == 0 {
-		t.Fatalf("mismatched data: expected %v, got %v", data, (*(*[10]byte)(unsafe.Pointer(cData)))[:])
-	}
-}
diff --git a/libgo/misc/cgo/test/issue1560.go b/libgo/misc/cgo/test/issue1560.go
deleted file mode 100644
index 30f61522257..00000000000
--- a/libgo/misc/cgo/test/issue1560.go
+++ /dev/null
@@ -1,50 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-// mysleep returns the absolute start time in ms.
-long long mysleep(int seconds);
-
-// twoSleep returns the absolute start time of the first sleep
-// in ms.
-long long twoSleep(int);
-*/
-import "C"
-
-import (
-	"testing"
-	"time"
-)
-
-var sleepDone = make(chan int64)
-
-// parallelSleep returns the absolute difference between the start time
-// of the two sleeps.
-func parallelSleep(n int) int64 {
-	t := int64(C.twoSleep(C.int(n))) - <-sleepDone
-	if t < 0 {
-		return -t
-	}
-	return t
-}
-
-//export BackgroundSleep
-func BackgroundSleep(n int32) {
-	go func() {
-		sleepDone <- int64(C.mysleep(C.int(n)))
-	}()
-}
-
-func testParallelSleep(t *testing.T) {
-	sleepSec := 1
-	dt := time.Duration(parallelSleep(sleepSec)) * time.Millisecond
-	t.Logf("difference in start time for two sleep(%d) is %v", sleepSec, dt)
-	// bug used to run sleeps in serial, producing a 2*sleepSec-second delay.
-	// we detect if the start times of those sleeps are > 0.5*sleepSec-second.
-	if dt >= time.Duration(sleepSec)*time.Second/2 {
-		t.Fatalf("parallel %d-second sleeps slept for %f seconds", sleepSec, dt.Seconds())
-	}
-}
diff --git a/libgo/misc/cgo/test/issue1635.go b/libgo/misc/cgo/test/issue1635.go
deleted file mode 100644
index 25899271c93..00000000000
--- a/libgo/misc/cgo/test/issue1635.go
+++ /dev/null
@@ -1,38 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-// Mac OS X's gcc will generate scattered relocation 2/1 for
-// this function on Darwin/386, and 8l couldn't handle it.
-// this example is in issue 1635
-#include <stdio.h>
-void scatter() {
-	void *p = scatter;
-	printf("scatter = %p\n", p);
-}
-
-// Adding this explicit extern declaration makes this a test for
-// https://gcc.gnu.org/PR68072 aka https://golang.org/issue/13344 .
-// It used to cause a cgo error when building with GCC 6.
-extern int hola;
-
-// this example is in issue 3253
-int hola = 0;
-int testHola() { return hola; }
-*/
-import "C"
-
-import "testing"
-
-func test1635(t *testing.T) {
-	C.scatter()
-	if v := C.hola; v != 0 {
-		t.Fatalf("C.hola is %d, should be 0", v)
-	}
-	if v := C.testHola(); v != 0 {
-		t.Fatalf("C.testHola() is %d, should be 0", v)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue17065.go b/libgo/misc/cgo/test/issue17065.go
deleted file mode 100644
index ede30bc3e63..00000000000
--- a/libgo/misc/cgo/test/issue17065.go
+++ /dev/null
@@ -1,29 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-// Test that C symbols larger than a page play nicely with the race detector.
-// See issue 17065.
-
-int ii[65537];
-*/
-import "C"
-
-import (
-	"runtime"
-	"testing"
-)
-
-var sink C.int
-
-func test17065(t *testing.T) {
-	if runtime.GOOS == "darwin" {
-		t.Skip("broken on darwin; issue 17065")
-	}
-	for i := range C.ii {
-		sink = C.ii[i]
-	}
-}
diff --git a/libgo/misc/cgo/test/issue17537.go b/libgo/misc/cgo/test/issue17537.go
deleted file mode 100644
index 777104e5122..00000000000
--- a/libgo/misc/cgo/test/issue17537.go
+++ /dev/null
@@ -1,58 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 17537.  The void* cast introduced by cgo to avoid problems
-// with const/volatile qualifiers breaks C preprocessor macros that
-// emulate functions.
-
-package cgotest
-
-/*
-#include <stdlib.h>
-
-typedef struct {
-	int i;
-} S17537;
-
-int I17537(S17537 *p);
-
-#define I17537(p) ((p)->i)
-
-// Calling this function used to fail without the cast.
-const int F17537(const char **p) {
-	return **p;
-}
-
-// Calling this function used to trigger an error from the C compiler
-// (issue 18298).
-void F18298(const void *const *p) {
-}
-
-// Test that conversions between typedefs work as they used to.
-typedef const void *T18298_1;
-struct S18298 { int i; };
-typedef const struct S18298 *T18298_2;
-void G18298(T18298_1 t) {
-}
-*/
-import "C"
-
-import "testing"
-
-func test17537(t *testing.T) {
-	v := C.S17537{i: 17537}
-	if got, want := C.I17537(&v), C.int(17537); got != want {
-		t.Errorf("got %d, want %d", got, want)
-	}
-
-	p := (*C.char)(C.malloc(1))
-	*p = 17
-	if got, want := C.F17537(&p), C.int(17); got != want {
-		t.Errorf("got %d, want %d", got, want)
-	}
-
-	C.F18298(nil)
-	var v18298 C.T18298_2
-	C.G18298(C.T18298_1(v18298))
-}
diff --git a/libgo/misc/cgo/test/issue18126.go b/libgo/misc/cgo/test/issue18126.go
deleted file mode 100644
index ac94a66aab7..00000000000
--- a/libgo/misc/cgo/test/issue18126.go
+++ /dev/null
@@ -1,26 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 18126: cgo check of void function returning errno.
-
-package cgotest
-
-/*
-#include <stdlib.h>
-
-void Issue18126C(void **p) {
-}
-*/
-import "C"
-
-import (
-	"testing"
-)
-
-func test18126(t *testing.T) {
-	p := C.malloc(1)
-	_, err := C.Issue18126C(&p)
-	C.free(p)
-	_ = err
-}
diff --git a/libgo/misc/cgo/test/issue18146.go b/libgo/misc/cgo/test/issue18146.go
index 8b7bb77b63b..196d98f5079 100644
--- a/libgo/misc/cgo/test/issue18146.go
+++ b/libgo/misc/cgo/test/issue18146.go
@@ -8,8 +8,6 @@
 
 package cgotest
 
-import "C"
-
 import (
 	"bytes"
 	"crypto/md5"
@@ -46,12 +44,12 @@ func test18146(t *testing.T) {
 	switch runtime.GOOS {
 	default:
 		setNproc = false
+	case "aix":
+		nproc = 9
 	case "linux":
 		nproc = 6
 	case "darwin", "dragonfly", "freebsd", "netbsd", "openbsd":
 		nproc = 7
-	case "aix":
-		nproc = 9
 	}
 	if setNproc {
 		var rlim syscall.Rlimit
diff --git a/libgo/misc/cgo/test/issue18720.go b/libgo/misc/cgo/test/issue18720.go
deleted file mode 100644
index 3d64003be74..00000000000
--- a/libgo/misc/cgo/test/issue18720.go
+++ /dev/null
@@ -1,54 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-#define HELLO "hello"
-#define WORLD "world"
-#define HELLO_WORLD HELLO "\000" WORLD
-
-struct foo { char c; };
-#define SIZE_OF(x) sizeof(x)
-#define SIZE_OF_FOO SIZE_OF(struct foo)
-#define VAR1 VAR
-#define VAR var
-int var = 5;
-
-#define ADDR &var
-
-#define CALL fn()
-int fn(void) {
-	return ++var;
-}
-*/
-import "C"
-import "testing"
-
-func test18720(t *testing.T) {
-	if got, want := C.HELLO_WORLD, "hello\000world"; got != want {
-		t.Errorf("C.HELLO_WORLD == %q, expected %q", got, want)
-	}
-
-	if got, want := C.VAR1, C.int(5); got != want {
-		t.Errorf("C.VAR1 == %v, expected %v", got, want)
-	}
-
-	if got, want := *C.ADDR, C.int(5); got != want {
-		t.Errorf("*C.ADDR == %v, expected %v", got, want)
-	}
-
-	if got, want := C.CALL, C.int(6); got != want {
-		t.Errorf("C.CALL == %v, expected %v", got, want)
-	}
-
-	if got, want := C.CALL, C.int(7); got != want {
-		t.Errorf("C.CALL == %v, expected %v", got, want)
-	}
-
-	// Issue 20125.
-	if got, want := C.SIZE_OF_FOO, 1; got != want {
-		t.Errorf("C.SIZE_OF_FOO == %v, expected %v", got, want)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue20129.go b/libgo/misc/cgo/test/issue20129.go
deleted file mode 100644
index e69e0e16efa..00000000000
--- a/libgo/misc/cgo/test/issue20129.go
+++ /dev/null
@@ -1,33 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-int issue20129 = 0;
-typedef void issue20129Void;
-issue20129Void issue20129Foo() {
-	issue20129 = 1;
-}
-typedef issue20129Void issue20129Void2;
-issue20129Void2 issue20129Bar() {
-	issue20129 = 2;
-}
-*/
-import "C"
-import "testing"
-
-func test20129(t *testing.T) {
-	if C.issue20129 != 0 {
-		t.Fatal("test is broken")
-	}
-	C.issue20129Foo()
-	if C.issue20129 != 1 {
-		t.Errorf("got %v but expected %v", C.issue20129, 1)
-	}
-	C.issue20129Bar()
-	if C.issue20129 != 2 {
-		t.Errorf("got %v but expected %v", C.issue20129, 2)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue20369.go b/libgo/misc/cgo/test/issue20369.go
deleted file mode 100644
index 37b4b78dfe1..00000000000
--- a/libgo/misc/cgo/test/issue20369.go
+++ /dev/null
@@ -1,20 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-#define UINT64_MAX        18446744073709551615ULL
-*/
-import "C"
-import (
-	"math"
-	"testing"
-)
-
-func test20369(t *testing.T) {
-	if C.UINT64_MAX != math.MaxUint64 {
-		t.Fatalf("got %v, want %v", uint64(C.UINT64_MAX), uint64(math.MaxUint64))
-	}
-}
diff --git a/libgo/misc/cgo/test/issue20910.go b/libgo/misc/cgo/test/issue20910.go
deleted file mode 100644
index 69d7d9249ac..00000000000
--- a/libgo/misc/cgo/test/issue20910.go
+++ /dev/null
@@ -1,19 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-//void callMulti(void);
-import "C"
-
-import "testing"
-
-//export multi
-func multi() (*C.char, C.int) {
-	return C.CString("multi"), 0
-}
-
-func test20910(t *testing.T) {
-	C.callMulti()
-}
diff --git a/libgo/misc/cgo/test/issue21708.go b/libgo/misc/cgo/test/issue21708.go
deleted file mode 100644
index d413e3c57a9..00000000000
--- a/libgo/misc/cgo/test/issue21708.go
+++ /dev/null
@@ -1,16 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-// #include <stdint.h>
-// #define CAST_TO_INT64 (int64_t)(-1)
-import "C"
-import "testing"
-
-func test21708(t *testing.T) {
-	if got, want := C.CAST_TO_INT64, -1; got != want {
-		t.Errorf("C.CAST_TO_INT64 == %v, expected %v", got, want)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue21809.go b/libgo/misc/cgo/test/issue21809.go
deleted file mode 100644
index a3a6b88897e..00000000000
--- a/libgo/misc/cgo/test/issue21809.go
+++ /dev/null
@@ -1,45 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-// Issue 21809.  Compile C `typedef` to go type aliases.
-
-// typedef long MySigned_t;
-// /* tests alias-to-alias */
-// typedef MySigned_t MySigned2_t;
-//
-// long takes_long(long x) { return x * x; }
-// MySigned_t takes_typedef(MySigned_t x) { return x * x; }
-import "C"
-
-import "testing"
-
-func test21809(t *testing.T) {
-	longVar := C.long(3)
-	typedefVar := C.MySigned_t(4)
-	typedefTypedefVar := C.MySigned2_t(5)
-
-	// all three should be considered identical to `long`
-	if ret := C.takes_long(longVar); ret != 9 {
-		t.Errorf("got %v but expected %v", ret, 9)
-	}
-	if ret := C.takes_long(typedefVar); ret != 16 {
-		t.Errorf("got %v but expected %v", ret, 16)
-	}
-	if ret := C.takes_long(typedefTypedefVar); ret != 25 {
-		t.Errorf("got %v but expected %v", ret, 25)
-	}
-
-	// They should also be identical to the typedef'd type
-	if ret := C.takes_typedef(longVar); ret != 9 {
-		t.Errorf("got %v but expected %v", ret, 9)
-	}
-	if ret := C.takes_typedef(typedefVar); ret != 16 {
-		t.Errorf("got %v but expected %v", ret, 16)
-	}
-	if ret := C.takes_typedef(typedefTypedefVar); ret != 25 {
-		t.Errorf("got %v but expected %v", ret, 25)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue22958.go b/libgo/misc/cgo/test/issue22958.go
deleted file mode 100644
index a5f058fdae1..00000000000
--- a/libgo/misc/cgo/test/issue22958.go
+++ /dev/null
@@ -1,24 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-// Test handling of bitfields.
-
-/*
-typedef struct {
-	unsigned long long f8  : 8;
-	unsigned long long f16 : 16;
-	unsigned long long f24 : 24;
-	unsigned long long f32 : 32;
-	unsigned long long f40 : 40;
-	unsigned long long f48 : 48;
-	unsigned long long f56 : 56;
-	unsigned long long f64 : 64;
-} issue22958Type;
-*/
-import "C"
-
-// Nothing to run, just make sure this compiles.
-var Vissue22958 C.issue22958Type
diff --git a/libgo/misc/cgo/test/issue23356.go b/libgo/misc/cgo/test/issue23356.go
deleted file mode 100644
index 1c390120c86..00000000000
--- a/libgo/misc/cgo/test/issue23356.go
+++ /dev/null
@@ -1,19 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-// int a(void) { return 5; };
-// int r(void) { return 3; };
-import "C"
-import "testing"
-
-func test23356(t *testing.T) {
-	if got, want := C.a(), C.int(5); got != want {
-		t.Errorf("C.a() == %v, expected %v", got, want)
-	}
-	if got, want := C.r(), C.int(3); got != want {
-		t.Errorf("C.r() == %v, expected %v", got, want)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue23720.go b/libgo/misc/cgo/test/issue23720.go
deleted file mode 100644
index 934fff3420a..00000000000
--- a/libgo/misc/cgo/test/issue23720.go
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Test that we can pass compatible typedefs.
-// No runtime test; just make sure it compiles.
-
-package cgotest
-
-/*
-typedef int *issue23720A;
-
-typedef const int *issue23720B;
-
-void issue23720F(issue23720B a) {}
-*/
-import "C"
-
-func Issue23720F() {
-	var x C.issue23720A
-	C.issue23720F(x)
-}
diff --git a/libgo/misc/cgo/test/issue24206.go b/libgo/misc/cgo/test/issue24206.go
deleted file mode 100644
index 5fec68e8803..00000000000
--- a/libgo/misc/cgo/test/issue24206.go
+++ /dev/null
@@ -1,54 +0,0 @@
-// +build amd64,linux
-
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-// Test that C.GoString uses IndexByte in safe manner.
-
-/*
-#include <sys/mman.h>
-
-// Returns string with null byte at the last valid address
-char* dangerousString1() {
-	int pageSize = 4096;
-	char *data = mmap(0, 2 * pageSize, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, 0, 0);
-	mprotect(data + pageSize,pageSize,PROT_NONE);
-	int start = pageSize - 123 - 1; // last 123 bytes of first page + 1 null byte
-	int i = start;
-	for (; i < pageSize; i++) {
-	data[i] = 'x';
-	}
-	data[pageSize -1 ] = 0;
-	return data+start;
-}
-
-char* dangerousString2() {
-	int pageSize = 4096;
-	char *data = mmap(0, 3 * pageSize, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, 0, 0);
-	mprotect(data + 2 * pageSize,pageSize,PROT_NONE);
-	int start = pageSize - 123 - 1; // last 123 bytes of first page + 1 null byte
-	int i = start;
-	for (; i < 2 * pageSize; i++) {
-	data[i] = 'x';
-	}
-	data[2*pageSize -1 ] = 0;
-	return data+start;
-}
-*/
-import "C"
-
-import (
-	"testing"
-)
-
-func test24206(t *testing.T) {
-	if l := len(C.GoString(C.dangerousString1())); l != 123 {
-		t.Errorf("Incorrect string length - got %d, want 123", l)
-	}
-	if l := len(C.GoString(C.dangerousString2())); l != 4096+123 {
-		t.Errorf("Incorrect string length - got %d, want %d", l, 4096+123)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue24206_generic.go b/libgo/misc/cgo/test/issue24206_generic.go
deleted file mode 100644
index 27c4d65f28e..00000000000
--- a/libgo/misc/cgo/test/issue24206_generic.go
+++ /dev/null
@@ -1,13 +0,0 @@
-// +build !amd64 !linux
-
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-import "testing"
-
-func test24206(t *testing.T) {
-	t.Skip("Skipping on non-amd64 or non-linux system")
-}
diff --git a/libgo/misc/cgo/test/issue2462.go b/libgo/misc/cgo/test/issue2462.go
deleted file mode 100644
index febca1eb085..00000000000
--- a/libgo/misc/cgo/test/issue2462.go
+++ /dev/null
@@ -1,102 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-import "C"
-
-//export exportbyte
-func exportbyte() byte {
-	return 0
-}
-
-//export exportbool
-func exportbool() bool {
-	return false
-}
-
-//export exportrune
-func exportrune() rune {
-	return 0
-}
-
-//export exporterror
-func exporterror() error {
-	return nil
-}
-
-//export exportint
-func exportint() int {
-	return 0
-}
-
-//export exportuint
-func exportuint() uint {
-	return 0
-}
-
-//export exportuintptr
-func exportuintptr() uintptr {
-	return (uintptr)(0)
-}
-
-//export exportint8
-func exportint8() int8 {
-	return 0
-}
-
-//export exportuint8
-func exportuint8() uint8 {
-	return 0
-}
-
-//export exportint16
-func exportint16() int16 {
-	return 0
-}
-
-//export exportuint16
-func exportuint16() uint16 {
-	return 0
-}
-
-//export exportint32
-func exportint32() int32 {
-	return 0
-}
-
-//export exportuint32
-func exportuint32() uint32 {
-	return 0
-}
-
-//export exportint64
-func exportint64() int64 {
-	return 0
-}
-
-//export exportuint64
-func exportuint64() uint64 {
-	return 0
-}
-
-//export exportfloat32
-func exportfloat32() float32 {
-	return 0
-}
-
-//export exportfloat64
-func exportfloat64() float64 {
-	return 0
-}
-
-//export exportcomplex64
-func exportcomplex64() complex64 {
-	return 0
-}
-
-//export exportcomplex128
-func exportcomplex128() complex128 {
-	return 0
-}
diff --git a/libgo/misc/cgo/test/issue25143.go b/libgo/misc/cgo/test/issue25143.go
deleted file mode 100644
index 607bfe4ba0f..00000000000
--- a/libgo/misc/cgo/test/issue25143.go
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-import "C"
-import "testing"
-
-func issue25143sum(ns ...C.int) C.int {
-	total := C.int(0)
-	for _, n := range ns {
-		total += n
-	}
-	return total
-}
-
-func test25143(t *testing.T) {
-	if got, want := issue25143sum(1, 2, 3), C.int(6); got != want {
-		t.Errorf("issue25143sum(1, 2, 3) == %v, expected %v", got, want)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue26066.go b/libgo/misc/cgo/test/issue26066.go
deleted file mode 100644
index 21028e7479b..00000000000
--- a/libgo/misc/cgo/test/issue26066.go
+++ /dev/null
@@ -1,19 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Wrong type of constant with GCC 8 and newer.
-
-package cgotest
-
-// const unsigned long long int issue26066 = (const unsigned long long) -1;
-import "C"
-
-import "testing"
-
-func test26066(t *testing.T) {
-	var i = int64(C.issue26066)
-	if i != -1 {
-		t.Errorf("got %d, want -1", i)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue26517.go b/libgo/misc/cgo/test/issue26517.go
deleted file mode 100644
index c1bf1c9213e..00000000000
--- a/libgo/misc/cgo/test/issue26517.go
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-// Introduce two pointer types which are distinct, but have the same
-// base type. Make sure that both of those pointer types get resolved
-// correctly. Before the fix for 26517 if one of these pointer types
-// was resolved before the other one was processed, the second one
-// would never be resolved.
-// Before this issue was fixed this test failed on Windows,
-// where va_list expands to a named char* type.
-
-/*
-#include <stdarg.h>
-typedef va_list TypeOne;
-typedef char *TypeTwo;
-*/
-import "C"
-
-var a C.TypeOne
-var b C.TypeTwo
diff --git a/libgo/misc/cgo/test/issue28545.go b/libgo/misc/cgo/test/issue28545.go
deleted file mode 100644
index 8419b89c0af..00000000000
--- a/libgo/misc/cgo/test/issue28545.go
+++ /dev/null
@@ -1,26 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Failed to add type conversion for negative constant.
-// Issue 28772: Failed to add type conversion for Go constant set to C constant.
-// No runtime test; just make sure it compiles.
-
-package cgotest
-
-/*
-#include <complex.h>
-
-#define issue28772Constant 1
-
-static void issue28545F(char **p, int n, complex double a) {}
-*/
-import "C"
-
-const issue28772Constant = C.issue28772Constant
-
-func issue28545G(p **C.char) {
-	C.issue28545F(p, -1, (0))
-	C.issue28545F(p, 2+3, complex(1, 1))
-	C.issue28545F(p, issue28772Constant, issue28772Constant2)
-}
diff --git a/libgo/misc/cgo/test/issue28772.go b/libgo/misc/cgo/test/issue28772.go
deleted file mode 100644
index bed786bf306..00000000000
--- a/libgo/misc/cgo/test/issue28772.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-// Constants didn't work if defined in different source file.
-
-// #define issue28772Constant2 2
-import "C"
-
-const issue28772Constant2 = C.issue28772Constant2
diff --git a/libgo/misc/cgo/test/issue28896.go b/libgo/misc/cgo/test/issue28896.go
deleted file mode 100644
index 8796040f18e..00000000000
--- a/libgo/misc/cgo/test/issue28896.go
+++ /dev/null
@@ -1,83 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// cgo was incorrectly adding padding after a packed struct.
-
-package cgotest
-
-/*
-#include <stddef.h>
-#include <stdint.h>
-#include <stdlib.h>
-
-typedef struct {
-	void *f1;
-	uint32_t f2;
-} __attribute__((__packed__)) innerPacked;
-
-typedef struct {
-	innerPacked g1;
-	uint64_t g2;
-} outerPacked;
-
-typedef struct {
-	void *f1;
-	uint32_t f2;
-} innerUnpacked;
-
-typedef struct {
-	innerUnpacked g1;
-	uint64_t g2;
-} outerUnpacked;
-
-size_t offset(int x) {
-	switch (x) {
-	case 0:
-		return offsetof(innerPacked, f2);
-	case 1:
-		return offsetof(outerPacked, g2);
-	case 2:
-		return offsetof(innerUnpacked, f2);
-	case 3:
-		return offsetof(outerUnpacked, g2);
-	default:
-		abort();
-	}
-}
-*/
-import "C"
-
-import (
-	"testing"
-	"unsafe"
-)
-
-func offset(i int) uintptr {
-	var pi C.innerPacked
-	var po C.outerPacked
-	var ui C.innerUnpacked
-	var uo C.outerUnpacked
-	switch i {
-	case 0:
-		return unsafe.Offsetof(pi.f2)
-	case 1:
-		return unsafe.Offsetof(po.g2)
-	case 2:
-		return unsafe.Offsetof(ui.f2)
-	case 3:
-		return unsafe.Offsetof(uo.g2)
-	default:
-		panic("can't happen")
-	}
-}
-
-func test28896(t *testing.T) {
-	for i := 0; i < 4; i++ {
-		c := uintptr(C.offset(C.int(i)))
-		g := offset(i)
-		if c != g {
-			t.Errorf("%d: C: %d != Go %d", i, c, g)
-		}
-	}
-}
diff --git a/libgo/misc/cgo/test/issue29383.go b/libgo/misc/cgo/test/issue29383.go
deleted file mode 100644
index 462c9a37df2..00000000000
--- a/libgo/misc/cgo/test/issue29383.go
+++ /dev/null
@@ -1,19 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// cgo's /*line*/ comments failed when inserted after '/',
-// because the result looked like a "//" comment.
-// No runtime test; just make sure it compiles.
-
-package cgotest
-
-// #include <stddef.h>
-import "C"
-
-func Issue29383(n, size uint) int {
-	if ^C.size_t(0)/C.size_t(n) < C.size_t(size) {
-		return 0
-	}
-	return 0
-}
diff --git a/libgo/misc/cgo/test/issue29748.go b/libgo/misc/cgo/test/issue29748.go
deleted file mode 100644
index 8229b3bcf08..00000000000
--- a/libgo/misc/cgo/test/issue29748.go
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Error handling a struct initializer that requires pointer checking.
-// Compilation test only, nothing to run.
-
-package cgotest
-
-// typedef struct { char **p; } S29748;
-// static int f29748(S29748 *p) { return 0; }
-import "C"
-
-var Vissue29748 = C.f29748(&C.S29748{
-	nil,
-})
-
-func Fissue299748() {
-	C.f29748(&C.S29748{
-		nil,
-	})
-}
diff --git a/libgo/misc/cgo/test/issue29781.go b/libgo/misc/cgo/test/issue29781.go
deleted file mode 100644
index 0fd8c08b8eb..00000000000
--- a/libgo/misc/cgo/test/issue29781.go
+++ /dev/null
@@ -1,17 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Error with newline inserted into constant expression.
-// Compilation test only, nothing to run.
-
-package cgotest
-
-// static void issue29781F(char **p, int n) {}
-// #define ISSUE29781C 0
-import "C"
-
-func issue29781G() {
-	var p *C.char
-	C.issue29781F(&p, C.ISSUE29781C+1)
-}
diff --git a/libgo/misc/cgo/test/issue30065.go b/libgo/misc/cgo/test/issue30065.go
deleted file mode 100644
index 396d437f7ab..00000000000
--- a/libgo/misc/cgo/test/issue30065.go
+++ /dev/null
@@ -1,38 +0,0 @@
-// Copyright 2019 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Don't make a private copy of an array when taking the address of an
-// element.
-
-package cgotest
-
-// #include <string.h>
-import "C"
-
-import (
-	"testing"
-	"unsafe"
-)
-
-func test30065(t *testing.T) {
-	var a [256]byte
-	b := []byte("a")
-	C.memcpy(unsafe.Pointer(&a), unsafe.Pointer(&b[0]), 1)
-	if a[0] != 'a' {
-		t.Errorf("&a failed: got %c, want %c", a[0], 'a')
-	}
-
-	b = []byte("b")
-	C.memcpy(unsafe.Pointer(&a[0]), unsafe.Pointer(&b[0]), 1)
-	if a[0] != 'b' {
-		t.Errorf("&a[0] failed: got %c, want %c", a[0], 'b')
-	}
-
-	d := make([]byte, 256)
-	b = []byte("c")
-	C.memcpy(unsafe.Pointer(&d[0]), unsafe.Pointer(&b[0]), 1)
-	if d[0] != 'c' {
-		t.Errorf("&d[0] failed: got %c, want %c", d[0], 'c')
-	}
-}
diff --git a/libgo/misc/cgo/test/issue3250.go b/libgo/misc/cgo/test/issue3250.go
deleted file mode 100644
index f85c16b2dce..00000000000
--- a/libgo/misc/cgo/test/issue3250.go
+++ /dev/null
@@ -1,95 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build !windows
-
-package cgotest
-
-/*
-#include <signal.h>
-#include <pthread.h>
-#include <unistd.h>
-#include <stdlib.h>
-
-static void *thread(void *p) {
-	const int M = 100;
-	int i;
-	(void)p;
-	for (i = 0; i < M; i++) {
-		pthread_kill(pthread_self(), SIGCHLD);
-		usleep(rand() % 20 + 5);
-	}
-	return NULL;
-}
-void testSendSIG() {
-	const int N = 20;
-	int i;
-	pthread_t tid[N];
-	for (i = 0; i < N; i++) {
-		usleep(rand() % 200 + 100);
-		pthread_create(&tid[i], 0, thread, NULL);
-	}
-	for (i = 0; i < N; i++)
-		pthread_join(tid[i], 0);
-}
-*/
-import "C"
-
-import (
-	"os"
-	"os/signal"
-	"syscall"
-	"testing"
-	"time"
-)
-
-func test3250(t *testing.T) {
-	t.Skip("skipped, see golang.org/issue/5885")
-	const (
-		thres = 1
-		sig   = syscall.SIGCHLD
-	)
-	type result struct {
-		n   int
-		sig os.Signal
-	}
-	var (
-		sigCh     = make(chan os.Signal, 10)
-		waitStart = make(chan struct{})
-		waitDone  = make(chan result)
-	)
-
-	signal.Notify(sigCh, sig)
-
-	go func() {
-		n := 0
-		alarm := time.After(time.Second * 3)
-		for {
-			select {
-			case <-waitStart:
-				waitStart = nil
-			case v := <-sigCh:
-				n++
-				if v != sig || n > thres {
-					waitDone <- result{n, v}
-					return
-				}
-			case <-alarm:
-				waitDone <- result{n, sig}
-				return
-			}
-		}
-	}()
-
-	waitStart <- struct{}{}
-	C.testSendSIG()
-	r := <-waitDone
-	if r.sig != sig {
-		t.Fatalf("received signal %v, but want %v", r.sig, sig)
-	}
-	t.Logf("got %d signals\n", r.n)
-	if r.n <= thres {
-		t.Fatalf("expected more than %d", thres)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue3261.go b/libgo/misc/cgo/test/issue3261.go
deleted file mode 100644
index 71375698d37..00000000000
--- a/libgo/misc/cgo/test/issue3261.go
+++ /dev/null
@@ -1,49 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-// libgcc on ARM might be compiled as thumb code, but our 5l
-// can't handle that, so we have to disable this test on arm.
-#ifdef __ARMEL__
-#include <stdio.h>
-int vabs(int x) {
-	puts("testLibgcc is disabled on ARM because 5l cannot handle thumb library.");
-	return (x < 0) ? -x : x;
-}
-#elif defined(__arm64__) && defined(__clang__)
-#include <stdio.h>
-int vabs(int x) {
-	puts("testLibgcc is disabled on ARM64 with clang due to lack of libgcc.");
-	return (x < 0) ? -x : x;
-}
-#else
-int __absvsi2(int); // dummy prototype for libgcc function
-// we shouldn't name the function abs, as gcc might use
-// the builtin one.
-int vabs(int x) { return __absvsi2(x); }
-#endif
-*/
-import "C"
-
-import "testing"
-
-func testLibgcc(t *testing.T) {
-	var table = []struct {
-		in, out C.int
-	}{
-		{0, 0},
-		{1, 1},
-		{-42, 42},
-		{1000300, 1000300},
-		{1 - 1<<31, 1<<31 - 1},
-	}
-	for _, v := range table {
-		if o := C.vabs(v.in); o != v.out {
-			t.Fatalf("abs(%d) got %d, should be %d", v.in, o, v.out)
-			return
-		}
-	}
-}
diff --git a/libgo/misc/cgo/test/issue3729.go b/libgo/misc/cgo/test/issue3729.go
deleted file mode 100644
index 947b90a00de..00000000000
--- a/libgo/misc/cgo/test/issue3729.go
+++ /dev/null
@@ -1,47 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 3729:	cmd/cgo: access errno from void C function
-// void f(void) returns [0]byte, error in Go world.
-
-// +build !windows
-
-package cgotest
-
-/*
-#include <errno.h>
-
-void g(void) {
-	errno = E2BIG;
-}
-
-// try to pass some non-trivial arguments to function g2
-const char _expA = 0x42;
-const float _expB = 3.14159;
-const short _expC = 0x55aa;
-const int _expD = 0xdeadbeef;
-void g2(int x, char a, float b, short c, int d) {
-	if (a == _expA && b == _expB && c == _expC && d == _expD)
-		errno = x;
-	else
-		errno = -1;
-}
-*/
-import "C"
-
-import (
-	"syscall"
-	"testing"
-)
-
-func test3729(t *testing.T) {
-	_, e := C.g()
-	if e != syscall.E2BIG {
-		t.Errorf("got %q, expect %q", e, syscall.E2BIG)
-	}
-	_, e = C.g2(C.EINVAL, C._expA, C._expB, C._expC, C._expD)
-	if e != syscall.EINVAL {
-		t.Errorf("got %q, expect %q", e, syscall.EINVAL)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue3729w.go b/libgo/misc/cgo/test/issue3729w.go
deleted file mode 100644
index 69296b506e7..00000000000
--- a/libgo/misc/cgo/test/issue3729w.go
+++ /dev/null
@@ -1,16 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 3729:	cmd/cgo: access errno from void C function
-// void f(void) returns [0]byte, error in Go world.
-
-// +build windows
-
-package cgotest
-
-import "testing"
-
-func test3729(t *testing.T) {
-	t.Log("skip errno test on Windows")
-}
diff --git a/libgo/misc/cgo/test/issue3741.go b/libgo/misc/cgo/test/issue3741.go
deleted file mode 100644
index 314038c1fe8..00000000000
--- a/libgo/misc/cgo/test/issue3741.go
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-import "C"
-
-//export exportSliceIn
-func exportSliceIn(s []byte) bool {
-	return len(s) == cap(s)
-}
-
-//export exportSliceOut
-func exportSliceOut() []byte {
-	return []byte{1}
-}
-
-//export exportSliceInOut
-func exportSliceInOut(s []byte) []byte {
-	return s
-}
diff --git a/libgo/misc/cgo/test/issue3775.go b/libgo/misc/cgo/test/issue3775.go
deleted file mode 100644
index 5aca7602c03..00000000000
--- a/libgo/misc/cgo/test/issue3775.go
+++ /dev/null
@@ -1,39 +0,0 @@
-// +build !android
-
-package cgotest
-
-/*
-void lockOSThreadCallback(void);
-inline static void lockOSThreadC(void)
-{
-        lockOSThreadCallback();
-}
-int usleep(unsigned usec);
-*/
-import "C"
-
-import (
-	"runtime"
-	"testing"
-)
-
-func init() {
-	// Same as test3775 but run during init so that
-	// there are two levels of internal runtime lock
-	// (1 for init, 1 for cgo).
-	// This would have been broken by CL 11663043.
-	C.lockOSThreadC()
-}
-
-func test3775(t *testing.T) {
-	// Used to panic because of the UnlockOSThread below.
-	C.lockOSThreadC()
-}
-
-//export lockOSThreadCallback
-func lockOSThreadCallback() {
-	runtime.LockOSThread()
-	runtime.UnlockOSThread()
-	go C.usleep(10000)
-	runtime.Gosched()
-}
diff --git a/libgo/misc/cgo/test/issue3945.go b/libgo/misc/cgo/test/issue3945.go
deleted file mode 100644
index 2f9fe23b8dc..00000000000
--- a/libgo/misc/cgo/test/issue3945.go
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-// Test that cgo reserves enough stack space during cgo call.
-// See https://golang.org/issue/3945 for details.
-
-// #include <stdio.h>
-//
-// void say() {
-//    printf("%s from C\n", "hello");
-// }
-//
-import "C"
-
-import "testing"
-
-func testPrintf(t *testing.T) {
-	C.say()
-}
diff --git a/libgo/misc/cgo/test/issue4054a.go b/libgo/misc/cgo/test/issue4054a.go
deleted file mode 100644
index 2abdac59047..00000000000
--- a/libgo/misc/cgo/test/issue4054a.go
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-typedef enum {
-	A = 0,
-	B,
-	C,
-	D,
-	E,
-	F,
-	G,
-	H,
-	I,
-	J,
-} issue4054a;
-*/
-import "C"
-
-var issue4054a = []int{C.A, C.B, C.C, C.D, C.E, C.F, C.G, C.H, C.I, C.J}
diff --git a/libgo/misc/cgo/test/issue4054b.go b/libgo/misc/cgo/test/issue4054b.go
deleted file mode 100644
index 048964c8937..00000000000
--- a/libgo/misc/cgo/test/issue4054b.go
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-typedef enum {
-	A = 0,
-	B,
-	C,
-	D,
-	E,
-	F,
-	G,
-	H,
-	I,
-	J,
-} issue4054b;
-*/
-import "C"
-
-var issue4054b = []int{C.A, C.B, C.C, C.D, C.E, C.F, C.G, C.H, C.I, C.J}
diff --git a/libgo/misc/cgo/test/issue4339.go b/libgo/misc/cgo/test/issue4339.go
deleted file mode 100644
index 3715fde5757..00000000000
--- a/libgo/misc/cgo/test/issue4339.go
+++ /dev/null
@@ -1,17 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-// We've historically permitted #include <>, so test it here.  Issue 29333.
-#include <issue4339.h>
-*/
-import "C"
-
-import "testing"
-
-func test4339(t *testing.T) {
-	C.handle4339(&C.exported4339)
-}
diff --git a/libgo/misc/cgo/test/issue4417.go b/libgo/misc/cgo/test/issue4417.go
deleted file mode 100644
index 9b182870d8e..00000000000
--- a/libgo/misc/cgo/test/issue4417.go
+++ /dev/null
@@ -1,42 +0,0 @@
-// Copyright 2012 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 4417:	cmd/cgo: bool alignment/padding issue.
-// bool alignment is wrong and causing wrong arguments when calling functions.
-//
-
-package cgotest
-
-/*
-#include <stdbool.h>
-
-static int c_bool(bool a, bool b, int c, bool d, bool e)  {
-   return c;
-}
-*/
-import "C"
-import "testing"
-
-func testBoolAlign(t *testing.T) {
-	b := C.c_bool(true, true, 10, true, false)
-	if b != 10 {
-		t.Fatalf("found %d expected 10\n", b)
-	}
-	b = C.c_bool(true, true, 5, true, true)
-	if b != 5 {
-		t.Fatalf("found %d expected 5\n", b)
-	}
-	b = C.c_bool(true, true, 3, true, false)
-	if b != 3 {
-		t.Fatalf("found %d expected 3\n", b)
-	}
-	b = C.c_bool(false, false, 1, true, false)
-	if b != 1 {
-		t.Fatalf("found %d expected 1\n", b)
-	}
-	b = C.c_bool(false, true, 200, true, false)
-	if b != 200 {
-		t.Fatalf("found %d expected 200\n", b)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue4857.go b/libgo/misc/cgo/test/issue4857.go
deleted file mode 100644
index b18979b5f7a..00000000000
--- a/libgo/misc/cgo/test/issue4857.go
+++ /dev/null
@@ -1,15 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-#cgo CFLAGS: -Werror
-const struct { int a; } *issue4857() { return (void *)0; }
-*/
-import "C"
-
-func test4857() {
-	_ = C.issue4857()
-}
diff --git a/libgo/misc/cgo/test/issue5227.go b/libgo/misc/cgo/test/issue5227.go
deleted file mode 100644
index 53c3bf12d74..00000000000
--- a/libgo/misc/cgo/test/issue5227.go
+++ /dev/null
@@ -1,38 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 5227: linker incorrectly treats common symbols and
-// leaves them undefined.
-
-package cgotest
-
-/*
-typedef struct {
-        int Count;
-} Fontinfo;
-
-Fontinfo SansTypeface;
-
-extern void init();
-
-Fontinfo loadfont() {
-        Fontinfo f = {0};
-        return f;
-}
-
-void init() {
-        SansTypeface = loadfont();
-}
-*/
-import "C"
-
-import "testing"
-
-func test5227(t *testing.T) {
-	C.init()
-}
-
-func selectfont() C.Fontinfo {
-	return C.SansTypeface
-}
diff --git a/libgo/misc/cgo/test/issue5242.go b/libgo/misc/cgo/test/issue5242.go
deleted file mode 100644
index c81cd409199..00000000000
--- a/libgo/misc/cgo/test/issue5242.go
+++ /dev/null
@@ -1,31 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 5242.  Cgo incorrectly computed the alignment of structs
-// with no Go accessible fields as 0, and then panicked on
-// modulo-by-zero computations.
-
-package cgotest
-
-/*
-typedef struct {
-} foo;
-
-typedef struct {
-	int x : 1;
-} bar;
-
-int issue5242(foo f, bar b) {
-	return 5242;
-}
-*/
-import "C"
-
-import "testing"
-
-func test5242(t *testing.T) {
-	if got := C.issue5242(C.foo{}, C.bar{}); got != 5242 {
-		t.Errorf("got %v", got)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue5337.go b/libgo/misc/cgo/test/issue5337.go
deleted file mode 100644
index 9041d95168d..00000000000
--- a/libgo/misc/cgo/test/issue5337.go
+++ /dev/null
@@ -1,31 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build !windows
-
-package cgotest
-
-/*
-#include <signal.h>
-#include <pthread.h>
-
-static void *thread1(void *p) {
-	(void)p;
-	pthread_kill(pthread_self(), SIGPROF);
-	return NULL;
-}
-void test5337() {
-	pthread_t tid;
-	pthread_create(&tid, 0, thread1, NULL);
-	pthread_join(tid, 0);
-}
-*/
-import "C"
-
-import "testing"
-
-// Verify that we can withstand SIGPROF received on foreign threads
-func test5337(t *testing.T) {
-	C.test5337()
-}
diff --git a/libgo/misc/cgo/test/issue5337w.go b/libgo/misc/cgo/test/issue5337w.go
deleted file mode 100644
index 7b467577007..00000000000
--- a/libgo/misc/cgo/test/issue5337w.go
+++ /dev/null
@@ -1,11 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build windows
-
-package cgotest
-
-import "testing"
-
-func test5337(t *testing.T) {}
diff --git a/libgo/misc/cgo/test/issue5548.go b/libgo/misc/cgo/test/issue5548.go
deleted file mode 100644
index 0710da79507..00000000000
--- a/libgo/misc/cgo/test/issue5548.go
+++ /dev/null
@@ -1,27 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-import "testing"
-
-/*
-extern int issue5548_in_c(void);
-*/
-import "C"
-
-//export issue5548FromC
-func issue5548FromC(s string, i int) int {
-	if len(s) == 4 && s == "test" && i == 42 {
-		return 12345
-	}
-	println("got", len(s), i)
-	return 9876
-}
-
-func test5548(t *testing.T) {
-	if x := C.issue5548_in_c(); x != 12345 {
-		t.Errorf("issue5548_in_c = %d, want %d", x, 12345)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue5603.go b/libgo/misc/cgo/test/issue5603.go
deleted file mode 100644
index ab84339e101..00000000000
--- a/libgo/misc/cgo/test/issue5603.go
+++ /dev/null
@@ -1,32 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-const long long issue5603exp = 0x12345678;
-long long issue5603foo0() { return issue5603exp; }
-long long issue5603foo1(void *p) { return issue5603exp; }
-long long issue5603foo2(void *p, void *q) { return issue5603exp; }
-long long issue5603foo3(void *p, void *q, void *r) { return issue5603exp; }
-long long issue5603foo4(void *p, void *q, void *r, void *s) { return issue5603exp; }
-*/
-import "C"
-
-import "testing"
-
-func test5603(t *testing.T) {
-	var x [5]int64
-	exp := int64(C.issue5603exp)
-	x[0] = int64(C.issue5603foo0())
-	x[1] = int64(C.issue5603foo1(nil))
-	x[2] = int64(C.issue5603foo2(nil, nil))
-	x[3] = int64(C.issue5603foo3(nil, nil, nil))
-	x[4] = int64(C.issue5603foo4(nil, nil, nil, nil))
-	for i, v := range x {
-		if v != exp {
-			t.Errorf("issue5603foo%d() returns %v, expected %v", i, v, exp)
-		}
-	}
-}
diff --git a/libgo/misc/cgo/test/issue5740.go b/libgo/misc/cgo/test/issue5740.go
deleted file mode 100644
index 059e316119d..00000000000
--- a/libgo/misc/cgo/test/issue5740.go
+++ /dev/null
@@ -1,15 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-// int test5740a(void), test5740b(void);
-import "C"
-import "testing"
-
-func test5740(t *testing.T) {
-	if v := C.test5740a() + C.test5740b(); v != 5 {
-		t.Errorf("expected 5, got %v", v)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue5986.go b/libgo/misc/cgo/test/issue5986.go
deleted file mode 100644
index 9be1614233e..00000000000
--- a/libgo/misc/cgo/test/issue5986.go
+++ /dev/null
@@ -1,33 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-#cgo LDFLAGS: -lm
-#include <stdio.h>
-#include <math.h>
-
-static void output5986()
-{
-    int current_row = 0, row_count = 0;
-    double sum_squares = 0;
-    double d;
-    do {
-        if (current_row == 10) {
-            current_row = 0;
-        }
-        ++row_count;
-    }
-    while (current_row++ != 1);
-    d =  sqrt(sum_squares / row_count);
-    printf("sqrt is: %g\n", d);
-}
-*/
-import "C"
-import "testing"
-
-func test5986(t *testing.T) {
-	C.output5986()
-}
diff --git a/libgo/misc/cgo/test/issue6128.go b/libgo/misc/cgo/test/issue6128.go
deleted file mode 100644
index 9832d799b94..00000000000
--- a/libgo/misc/cgo/test/issue6128.go
+++ /dev/null
@@ -1,20 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-// Test handling of #defined names in clang.
-// golang.org/issue/6128.
-
-/*
-// NOTE: Must use hex, or else a shortcut for decimals
-// in cgo avoids trying to pass this to clang.
-#define X 0x1
-*/
-import "C"
-
-func test6128() {
-	// nothing to run, just make sure this compiles.
-	_ = C.X
-}
diff --git a/libgo/misc/cgo/test/issue6390.go b/libgo/misc/cgo/test/issue6390.go
deleted file mode 100644
index 5642899c587..00000000000
--- a/libgo/misc/cgo/test/issue6390.go
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-// #include <stdlib.h>
-import "C"
-
-import "testing"
-
-func test6390(t *testing.T) {
-	p1 := C.malloc(1024)
-	if p1 == nil {
-		t.Fatalf("C.malloc(1024) returned nil")
-	}
-	p2 := C.malloc(0)
-	if p2 == nil {
-		t.Fatalf("C.malloc(0) returned nil")
-	}
-	C.free(p1)
-	C.free(p2)
-}
diff --git a/libgo/misc/cgo/test/issue6472.go b/libgo/misc/cgo/test/issue6472.go
deleted file mode 100644
index d416a05e29d..00000000000
--- a/libgo/misc/cgo/test/issue6472.go
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-typedef struct
-{
-        struct
-        {
-            int x;
-        } y[16];
-} z;
-*/
-import "C"
-
-func test6472() {
-	// nothing to run, just make sure this compiles
-	s := new(C.z)
-	println(s.y[0].x)
-}
diff --git a/libgo/misc/cgo/test/issue6506.go b/libgo/misc/cgo/test/issue6506.go
deleted file mode 100644
index c54b54b64fc..00000000000
--- a/libgo/misc/cgo/test/issue6506.go
+++ /dev/null
@@ -1,36 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-// Test handling of size_t in the face of incorrect clang debug information.
-// golang.org/issue/6506.
-
-/*
-#include <stdlib.h>
-#include <string.h>
-*/
-import "C"
-
-func test6506() {
-	// nothing to run, just make sure this compiles
-	var x C.size_t
-
-	C.calloc(x, x)
-	C.malloc(x)
-	C.realloc(nil, x)
-	C.memcpy(nil, nil, x)
-	C.memcmp(nil, nil, x)
-	C.memmove(nil, nil, x)
-	C.strncpy(nil, nil, x)
-	C.strncmp(nil, nil, x)
-	C.strncat(nil, nil, x)
-	x = C.strxfrm(nil, nil, x)
-	C.memchr(nil, 0, x)
-	x = C.strcspn(nil, nil)
-	x = C.strspn(nil, nil)
-	C.memset(nil, 0, x)
-	x = C.strlen(nil)
-	_ = x
-}
diff --git a/libgo/misc/cgo/test/issue6612.go b/libgo/misc/cgo/test/issue6612.go
deleted file mode 100644
index 15a12fab38f..00000000000
--- a/libgo/misc/cgo/test/issue6612.go
+++ /dev/null
@@ -1,90 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// golang.org/issue/6612
-// Test new scheme for deciding whether C.name is an expression, type, constant.
-// Clang silences some warnings when the name is a #defined macro, so test those too
-// (even though we now use errors exclusively, not warnings).
-
-package cgotest
-
-/*
-void myfunc(void) {}
-int myvar = 5;
-const char *mytext = "abcdef";
-typedef int mytype;
-enum {
-	myenum = 1234,
-};
-
-#define myfunc_def myfunc
-#define myvar_def myvar
-#define mytext_def mytext
-#define mytype_def mytype
-#define myenum_def myenum
-#define myint_def 12345
-#define myfloat_def 1.5
-#define mystring_def "hello"
-*/
-import "C"
-
-import "testing"
-
-func testNaming(t *testing.T) {
-	C.myfunc()
-	C.myfunc_def()
-	if v := C.myvar; v != 5 {
-		t.Errorf("C.myvar = %d, want 5", v)
-	}
-	if v := C.myvar_def; v != 5 {
-		t.Errorf("C.myvar_def = %d, want 5", v)
-	}
-	if s := C.GoString(C.mytext); s != "abcdef" {
-		t.Errorf("C.mytext = %q, want %q", s, "abcdef")
-	}
-	if s := C.GoString(C.mytext_def); s != "abcdef" {
-		t.Errorf("C.mytext_def = %q, want %q", s, "abcdef")
-	}
-	if c := C.myenum; c != 1234 {
-		t.Errorf("C.myenum = %v, want 1234", c)
-	}
-	if c := C.myenum_def; c != 1234 {
-		t.Errorf("C.myenum_def = %v, want 1234", c)
-	}
-	{
-		const c = C.myenum
-		if c != 1234 {
-			t.Errorf("C.myenum as const = %v, want 1234", c)
-		}
-	}
-	{
-		const c = C.myenum_def
-		if c != 1234 {
-			t.Errorf("C.myenum as const = %v, want 1234", c)
-		}
-	}
-	if c := C.myint_def; c != 12345 {
-		t.Errorf("C.myint_def = %v, want 12345", c)
-	}
-	{
-		const c = C.myint_def
-		if c != 12345 {
-			t.Errorf("C.myint as const = %v, want 12345", c)
-		}
-	}
-
-	if c := C.myfloat_def; c != 1.5 {
-		t.Errorf("C.myint_def = %v, want 1.5", c)
-	}
-	{
-		const c = C.myfloat_def
-		if c != 1.5 {
-			t.Errorf("C.myint as const = %v, want 1.5", c)
-		}
-	}
-
-	if s := C.mystring_def; s != "hello" {
-		t.Errorf("C.mystring_def = %q, want %q", s, "hello")
-	}
-}
diff --git a/libgo/misc/cgo/test/issue6833.go b/libgo/misc/cgo/test/issue6833.go
deleted file mode 100644
index de60dbfcf20..00000000000
--- a/libgo/misc/cgo/test/issue6833.go
+++ /dev/null
@@ -1,27 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-extern unsigned long long issue6833Func(unsigned int, unsigned long long);
-*/
-import "C"
-
-import "testing"
-
-//export GoIssue6833Func
-func GoIssue6833Func(aui uint, aui64 uint64) uint64 {
-	return aui64 + uint64(aui)
-}
-
-func test6833(t *testing.T) {
-	ui := 7
-	ull := uint64(0x4000300020001000)
-	v := uint64(C.issue6833Func(C.uint(ui), C.ulonglong(ull)))
-	exp := uint64(ui) + ull
-	if v != exp {
-		t.Errorf("issue6833Func() returns %x, expected %x", v, exp)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue6907.go b/libgo/misc/cgo/test/issue6907.go
deleted file mode 100644
index 00495ab8e2e..00000000000
--- a/libgo/misc/cgo/test/issue6907.go
+++ /dev/null
@@ -1,33 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-#include <stdlib.h>
-#include <string.h>
-
-char* Issue6907CopyString(_GoString_ s) {
-	size_t n;
-	const char *p;
-	char *r;
-
-	n = _GoStringLen(s);
-	p = _GoStringPtr(s);
-	r = malloc(n + 1);
-	memmove(r, p, n);
-	r[n] = '\0';
-	return r;
-}
-*/
-import "C"
-
-import "testing"
-
-func test6907(t *testing.T) {
-	want := "yarn"
-	if got := C.GoString(C.Issue6907CopyString(want)); got != want {
-		t.Errorf("C.GoString(C.Issue6907CopyString(%q)) == %q, want %q", want, got, want)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue6907export.go b/libgo/misc/cgo/test/issue6907export.go
deleted file mode 100644
index d41899e1a62..00000000000
--- a/libgo/misc/cgo/test/issue6907export.go
+++ /dev/null
@@ -1,30 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-extern int CheckIssue6907C(_GoString_);
-*/
-import "C"
-
-import (
-	"testing"
-)
-
-const CString = "C string"
-
-//export CheckIssue6907Go
-func CheckIssue6907Go(s string) C.int {
-	if s == CString {
-		return 1
-	}
-	return 0
-}
-
-func test6907Go(t *testing.T) {
-	if got := C.CheckIssue6907C(CString); got != 1 {
-		t.Errorf("C.CheckIssue6907C() == %d, want %d", got, 1)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue7560.go b/libgo/misc/cgo/test/issue7560.go
deleted file mode 100644
index f36d8a10234..00000000000
--- a/libgo/misc/cgo/test/issue7560.go
+++ /dev/null
@@ -1,44 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-#include <stdint.h>
-
-typedef struct {
-	char x;
-	long y;
-} __attribute__((__packed__)) misaligned;
-
-int
-offset7560(void)
-{
-	return (uintptr_t)&((misaligned*)0)->y;
-}
-*/
-import "C"
-
-import (
-	"reflect"
-	"testing"
-)
-
-func test7560(t *testing.T) {
-	// some mingw don't implement __packed__ correctly.
-	if C.offset7560() != 1 {
-		t.Skip("C compiler did not pack struct")
-	}
-
-	// C.misaligned should have x but then a padding field to get to the end of the struct.
-	// There should not be a field named 'y'.
-	var v C.misaligned
-	rt := reflect.TypeOf(&v).Elem()
-	if rt.NumField() != 2 || rt.Field(0).Name != "x" || rt.Field(1).Name != "_" {
-		t.Errorf("unexpected fields in C.misaligned:\n")
-		for i := 0; i < rt.NumField(); i++ {
-			t.Logf("%+v\n", rt.Field(i))
-		}
-	}
-}
diff --git a/libgo/misc/cgo/test/issue7665.go b/libgo/misc/cgo/test/issue7665.go
deleted file mode 100644
index ce0345845f9..00000000000
--- a/libgo/misc/cgo/test/issue7665.go
+++ /dev/null
@@ -1,25 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-import (
-	"testing"
-	"unsafe"
-)
-
-// extern void f7665(void);
-import "C"
-
-//export f7665
-func f7665() {}
-
-var bad7665 unsafe.Pointer = C.f7665
-var good7665 uintptr = uintptr(C.f7665)
-
-func test7665(t *testing.T) {
-	if bad7665 == nil || uintptr(bad7665) != good7665 {
-		t.Errorf("ptrs = %p, %#x, want same non-nil pointer", bad7665, good7665)
-	}
-}
diff --git a/libgo/misc/cgo/test/issue7786.go b/libgo/misc/cgo/test/issue7786.go
deleted file mode 100644
index 1344e9eda62..00000000000
--- a/libgo/misc/cgo/test/issue7786.go
+++ /dev/null
@@ -1,51 +0,0 @@
-// Copyright 2013 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 7786. No runtime test, just make sure that typedef and struct/union/class are interchangeable at compile time.
-
-package cgotest
-
-// struct test7786;
-// typedef struct test7786 typedef_test7786;
-// void f7786(struct test7786 *ctx) {}
-// void g7786(typedef_test7786 *ctx) {}
-//
-// typedef struct body7786 typedef_body7786;
-// struct body7786 { int x; };
-// void b7786(struct body7786 *ctx) {}
-// void c7786(typedef_body7786 *ctx) {}
-//
-// typedef union union7786 typedef_union7786;
-// void u7786(union union7786 *ctx) {}
-// void v7786(typedef_union7786 *ctx) {}
-import "C"
-
-func f() {
-	var x1 *C.typedef_test7786
-	var x2 *C.struct_test7786
-	x1 = x2
-	x2 = x1
-	C.f7786(x1)
-	C.f7786(x2)
-	C.g7786(x1)
-	C.g7786(x2)
-
-	var b1 *C.typedef_body7786
-	var b2 *C.struct_body7786
-	b1 = b2
-	b2 = b1
-	C.b7786(b1)
-	C.b7786(b2)
-	C.c7786(b1)
-	C.c7786(b2)
-
-	var u1 *C.typedef_union7786
-	var u2 *C.union_union7786
-	u1 = u2
-	u2 = u1
-	C.u7786(u1)
-	C.u7786(u2)
-	C.v7786(u1)
-	C.v7786(u2)
-}
diff --git a/libgo/misc/cgo/test/issue7978.go b/libgo/misc/cgo/test/issue7978.go
deleted file mode 100644
index f0809d35d80..00000000000
--- a/libgo/misc/cgo/test/issue7978.go
+++ /dev/null
@@ -1,115 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 7978.  Stack tracing didn't work during cgo code after calling a Go
-// callback.  Make sure GC works and the stack trace is correct.
-
-package cgotest
-
-/*
-#include <stdint.h>
-
-void issue7978cb(void);
-
-// use ugly atomic variable sync since that doesn't require calling back into
-// Go code or OS dependencies
-static void issue7978c(uint32_t *sync) {
-	while(__atomic_load_n(sync, __ATOMIC_SEQ_CST) != 0)
-		;
-	__atomic_add_fetch(sync, 1, __ATOMIC_SEQ_CST);
-	while(__atomic_load_n(sync, __ATOMIC_SEQ_CST) != 2)
-		;
-	issue7978cb();
-	__atomic_add_fetch(sync, 1, __ATOMIC_SEQ_CST);
-	while(__atomic_load_n(sync, __ATOMIC_SEQ_CST) != 6)
-		;
-}
-*/
-import "C"
-
-import (
-	"runtime"
-	"runtime/debug"
-	"strings"
-	"sync/atomic"
-	"testing"
-)
-
-var issue7978sync uint32
-
-func issue7978check(t *testing.T, wantFunc string, badFunc string, depth int) {
-	runtime.GC()
-	buf := make([]byte, 65536)
-	trace := string(buf[:runtime.Stack(buf, true)])
-	for _, goroutine := range strings.Split(trace, "\n\n") {
-		if strings.Contains(goroutine, "test.issue7978go") {
-			trace := strings.Split(goroutine, "\n")
-			// look for the expected function in the stack
-			for i := 0; i < depth; i++ {
-				if badFunc != "" && strings.Contains(trace[1+2*i], badFunc) {
-					t.Errorf("bad stack: found %s in the stack:\n%s", badFunc, goroutine)
-					return
-				}
-				if strings.Contains(trace[1+2*i], wantFunc) {
-					return
-				}
-			}
-			t.Errorf("bad stack: didn't find %s in the stack:\n%s", wantFunc, goroutine)
-			return
-		}
-	}
-	t.Errorf("bad stack: goroutine not found. Full stack dump:\n%s", trace)
-}
-
-func issue7978wait(store uint32, wait uint32) {
-	if store != 0 {
-		atomic.StoreUint32(&issue7978sync, store)
-	}
-	for atomic.LoadUint32(&issue7978sync) != wait {
-		runtime.Gosched()
-	}
-}
-
-//export issue7978cb
-func issue7978cb() {
-	// Force a stack growth from the callback to put extra
-	// pressure on the runtime. See issue #17785.
-	growStack(64)
-	issue7978wait(3, 4)
-}
-
-func growStack(n int) int {
-	var buf [128]int
-	if n == 0 {
-		return 0
-	}
-	return buf[growStack(n-1)]
-}
-
-func issue7978go() {
-	C.issue7978c((*C.uint32_t)(&issue7978sync))
-	issue7978wait(7, 8)
-}
-
-func test7978(t *testing.T) {
-	if runtime.Compiler == "gccgo" {
-		t.Skip("gccgo can not do stack traces of C code")
-	}
-	debug.SetTraceback("2")
-	issue7978sync = 0
-	go issue7978go()
-	// test in c code, before callback
-	issue7978wait(0, 1)
-	issue7978check(t, "_Cfunc_issue7978c(", "", 1)
-	// test in go code, during callback
-	issue7978wait(2, 3)
-	issue7978check(t, "test.issue7978cb(", "test.issue7978go", 3)
-	// test in c code, after callback
-	issue7978wait(4, 5)
-	issue7978check(t, "_Cfunc_issue7978c(", "_cgoexpwrap", 1)
-	// test in go code, after return from cgo
-	issue7978wait(6, 7)
-	issue7978check(t, "test.issue7978go(", "", 3)
-	atomic.StoreUint32(&issue7978sync, 8)
-}
diff --git a/libgo/misc/cgo/test/issue8092.go b/libgo/misc/cgo/test/issue8092.go
deleted file mode 100644
index 19123e79cfa..00000000000
--- a/libgo/misc/cgo/test/issue8092.go
+++ /dev/null
@@ -1,36 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 8092. Test that linker defined symbols (e.g., text, data) don't
-// conflict with C symbols.
-
-package cgotest
-
-/*
-char text[] = "text";
-char data[] = "data";
-char *ctext(void) { return text; }
-char *cdata(void) { return data; }
-*/
-import "C"
-
-import "testing"
-
-func test8092(t *testing.T) {
-	tests := []struct {
-		s    string
-		a, b *C.char
-	}{
-		{"text", &C.text[0], C.ctext()},
-		{"data", &C.data[0], C.cdata()},
-	}
-	for _, test := range tests {
-		if test.a != test.b {
-			t.Errorf("%s: pointer mismatch: %v != %v", test.s, test.a, test.b)
-		}
-		if got := C.GoString(test.a); got != test.s {
-			t.Errorf("%s: points at %#v, want %#v", test.s, got, test.s)
-		}
-	}
-}
diff --git a/libgo/misc/cgo/test/issue8331a.go b/libgo/misc/cgo/test/issue8331a.go
deleted file mode 100644
index 92e2579e7ae..00000000000
--- a/libgo/misc/cgo/test/issue8331a.go
+++ /dev/null
@@ -1,15 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 8331.  A typedef of an unnamed struct is the same struct when
-// #include'd twice.  No runtime test; just make sure it compiles.
-
-package cgotest
-
-// #include "issue8331.h"
-import "C"
-
-func issue8331a() C.issue8331 {
-	return issue8331Var
-}
diff --git a/libgo/misc/cgo/test/issue8331b.go b/libgo/misc/cgo/test/issue8331b.go
deleted file mode 100644
index 5324aa2a175..00000000000
--- a/libgo/misc/cgo/test/issue8331b.go
+++ /dev/null
@@ -1,13 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 8331.  A typedef of an unnamed struct is the same struct when
-// #include'd twice.  No runtime test; just make sure it compiles.
-
-package cgotest
-
-// #include "issue8331.h"
-import "C"
-
-var issue8331Var C.issue8331
diff --git a/libgo/misc/cgo/test/issue8428.go b/libgo/misc/cgo/test/issue8428.go
deleted file mode 100644
index 2e5a555b582..00000000000
--- a/libgo/misc/cgo/test/issue8428.go
+++ /dev/null
@@ -1,55 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// This test fails on older versions of OS X because they use older buggy
-// versions of Clang that emit ambiguous DWARF info.  See issue 8611.
-// +build !darwin
-
-package cgotest
-
-// Issue 8428.  Cgo inconsistently translated zero size arrays.
-
-/*
-struct issue8428one {
-	char b;
-	char rest[];
-};
-
-struct issue8428two {
-	void *p;
-	char b;
-	char rest[0];
-	char pad;
-};
-
-struct issue8428three {
-	char w[1][2][3][0];
-	char x[2][3][0][1];
-	char y[3][0][1][2];
-	char z[0][1][2][3];
-};
-*/
-import "C"
-
-import "unsafe"
-
-var _ = C.struct_issue8428one{
-	b: C.char(0),
-	// The trailing rest field is not available in cgo.
-	// See issue 11925.
-	// rest: [0]C.char{},
-}
-
-var _ = C.struct_issue8428two{
-	p:    unsafe.Pointer(nil),
-	b:    C.char(0),
-	rest: [0]C.char{},
-}
-
-var _ = C.struct_issue8428three{
-	w: [1][2][3][0]C.char{},
-	x: [2][3][0][1]C.char{},
-	y: [3][0][1][2]C.char{},
-	z: [0][1][2][3]C.char{},
-}
diff --git a/libgo/misc/cgo/test/issue8441.go b/libgo/misc/cgo/test/issue8441.go
deleted file mode 100644
index 4489ca9eb67..00000000000
--- a/libgo/misc/cgo/test/issue8441.go
+++ /dev/null
@@ -1,27 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Issue 8368 and 8441.  Recursive struct definitions didn't work.
-// No runtime test; just make sure it compiles.
-
-package cgotest
-
-/*
-typedef struct one one;
-typedef struct two two;
-struct one {
-	two *x;
-};
-struct two {
-	one *x;
-};
-*/
-import "C"
-
-func issue8368(one *C.struct_one, two *C.struct_two) {
-}
-
-func issue8441(one *C.one, two *C.two) {
-	issue8441(two.x, one.x)
-}
diff --git a/libgo/misc/cgo/test/issue8811.go b/libgo/misc/cgo/test/issue8811.go
deleted file mode 100644
index f812732cfd7..00000000000
--- a/libgo/misc/cgo/test/issue8811.go
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package cgotest
-
-/*
-extern int issue8811Initialized;
-extern void issue8811Init();
-
-void issue8811Execute() {
-	if(!issue8811Initialized)
-		issue8811Init();
-}
-*/
-import "C"
-
-import "testing"
-
-func test8811(t *testing.T) {
-	C.issue8811Execute()
-}
diff --git a/libgo/misc/cgo/test/issue9557.go b/libgo/misc/cgo/test/issue9557.go
deleted file mode 100644
index 4e8922a69c6..00000000000
--- a/libgo/misc/cgo/test/issue9557.go
+++ /dev/null
@@ -1,36 +0,0 @@
-// Copyright 2015 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// cgo rewrote C.var to *_Cvar_var, but left
-// C.var.field as _Cvar.var.field.  It now rewrites
-// the latter as (*_Cvar_var).field.
-// See https://golang.org/issue/9557.
-
-package cgotest
-
-// struct issue9557_t {
-//   int a;
-// } test9557bar = { 42 };
-//
-// struct issue9557_t *issue9557foo = &test9557bar;
-import "C"
-import "testing"
-
-func test9557(t *testing.T) {
-	// implicitly dereference a Go variable
-	foo := C.issue9557foo
-	if v := foo.a; v != 42 {
-		t.Fatalf("foo.a expected 42, but got %d", v)
-	}
-
-	// explicitly dereference a C variable
-	if v := (*C.issue9557foo).a; v != 42 {
-		t.Fatalf("(*C.issue9557foo).a expected 42, but is %d", v)
-	}
-
-	// implicitly dereference a C variable
-	if v := C.issue9557foo.a; v != 42 {
-		t.Fatalf("C.issue9557foo.a expected 42, but is %d", v)
-	}
-}
diff --git a/libgo/misc/cgo/test/overlaydir_test.go b/libgo/misc/cgo/test/overlaydir_test.go
new file mode 100644
index 00000000000..1b5c67de70f
--- /dev/null
+++ b/libgo/misc/cgo/test/overlaydir_test.go
@@ -0,0 +1,81 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cgotest
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// overlayDir makes a minimal-overhead copy of srcRoot in which new files may be added.
+//
+// TODO: Once we no longer need to support the misc module in GOPATH mode,
+// factor this function out into a package to reduce duplication.
+func overlayDir(dstRoot, srcRoot string) error {
+	dstRoot = filepath.Clean(dstRoot)
+	if err := os.MkdirAll(dstRoot, 0777); err != nil {
+		return err
+	}
+
+	symBase, err := filepath.Rel(srcRoot, dstRoot)
+	if err != nil {
+		symBase, err = filepath.Abs(srcRoot)
+		if err != nil {
+			return err
+		}
+	}
+
+	return filepath.Walk(srcRoot, func(srcPath string, info os.FileInfo, err error) error {
+		if err != nil || srcPath == srcRoot {
+			return err
+		}
+
+		suffix := strings.TrimPrefix(srcPath, srcRoot)
+		for len(suffix) > 0 && suffix[0] == filepath.Separator {
+			suffix = suffix[1:]
+		}
+		dstPath := filepath.Join(dstRoot, suffix)
+
+		perm := info.Mode() & os.ModePerm
+		if info.Mode()&os.ModeSymlink != 0 {
+			info, err = os.Stat(srcPath)
+			if err != nil {
+				return err
+			}
+			perm = info.Mode() & os.ModePerm
+		}
+
+		// Always copy directories (don't symlink them).
+		// If we add a file in the overlay, we don't want to add it in the original.
+		if info.IsDir() {
+			return os.Mkdir(dstPath, perm)
+		}
+
+		// If the OS supports symlinks, use them instead of copying bytes.
+		if err := os.Symlink(filepath.Join(symBase, suffix), dstPath); err == nil {
+			return nil
+		}
+
+		// Otherwise, copy the bytes.
+		src, err := os.Open(srcPath)
+		if err != nil {
+			return err
+		}
+		defer src.Close()
+
+		dst, err := os.OpenFile(dstPath, os.O_WRONLY|os.O_CREATE|os.O_EXCL, perm)
+		if err != nil {
+			return err
+		}
+
+		_, err = io.Copy(dst, src)
+		if closeErr := dst.Close(); err == nil {
+			err = closeErr
+		}
+		return err
+	})
+}
diff --git a/libgo/misc/cgo/test/pkg_test.go b/libgo/misc/cgo/test/pkg_test.go
new file mode 100644
index 00000000000..08e075c022c
--- /dev/null
+++ b/libgo/misc/cgo/test/pkg_test.go
@@ -0,0 +1,69 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cgotest
+
+import (
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+)
+
+// TestCrossPackageTests compiles and runs tests that depend on imports of other
+// local packages, using source code stored in the testdata directory.
+//
+// The tests in the misc directory tree do not have a valid import path in
+// GOPATH mode, so they previously used relative imports. However, relative
+// imports do not work in module mode. In order to make the test work in both
+// modes, we synthesize a GOPATH in which the module paths are equivalent, and
+// run the tests as a subprocess.
+//
+// If and when we no longer support these tests in GOPATH mode, we can remove
+// this shim and move the tests currently located in testdata back into the
+// parent directory.
+func TestCrossPackageTests(t *testing.T) {
+	switch runtime.GOOS {
+	case "android":
+		t.Skip("Can't exec cmd/go subprocess on Android.")
+	case "darwin":
+		switch runtime.GOARCH {
+		case "arm", "arm64":
+			t.Skip("Can't exec cmd/go subprocess on iOS.")
+		}
+	}
+
+	GOPATH, err := ioutil.TempDir("", "cgotest")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(GOPATH)
+
+	modRoot := filepath.Join(GOPATH, "src", "cgotest")
+	if err := overlayDir(modRoot, "testdata"); err != nil {
+		t.Fatal(err)
+	}
+	if err := ioutil.WriteFile(filepath.Join(modRoot, "go.mod"), []byte("module cgotest\n"), 0666); err != nil {
+		t.Fatal(err)
+	}
+
+	cmd := exec.Command("go", "test")
+	if testing.Verbose() {
+		cmd.Args = append(cmd.Args, "-v")
+	}
+	if testing.Short() {
+		cmd.Args = append(cmd.Args, "-short")
+	}
+	cmd.Dir = modRoot
+	cmd.Env = append(os.Environ(), "GOPATH="+GOPATH, "PWD="+cmd.Dir)
+	out, err := cmd.CombinedOutput()
+	if err == nil {
+		t.Logf("%s:\n%s", strings.Join(cmd.Args, " "), out)
+	} else {
+		t.Fatalf("%s: %s\n%s", strings.Join(cmd.Args, " "), err, out)
+	}
+}
diff --git a/libgo/misc/cgo/test/sigaltstack.go b/libgo/misc/cgo/test/sigaltstack.go
index 2b7a1ec9ad0..2c9b81ced7a 100644
--- a/libgo/misc/cgo/test/sigaltstack.go
+++ b/libgo/misc/cgo/test/sigaltstack.go
@@ -55,7 +55,7 @@ import (
 
 func testSigaltstack(t *testing.T) {
 	switch {
-	case runtime.GOOS == "solaris", runtime.GOOS == "darwin" && (runtime.GOARCH == "arm" || runtime.GOARCH == "arm64"):
+	case runtime.GOOS == "solaris", runtime.GOOS == "illumos", runtime.GOOS == "darwin" && (runtime.GOARCH == "arm" || runtime.GOARCH == "arm64"):
 		t.Skipf("switching signal stack not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
 	case runtime.GOOS == "darwin" && runtime.GOARCH == "386":
 		t.Skipf("sigaltstack fails on darwin/386")
diff --git a/libgo/misc/cgo/test/test.go b/libgo/misc/cgo/test/test.go
new file mode 100644
index 00000000000..2d060bfeac4
--- /dev/null
+++ b/libgo/misc/cgo/test/test.go
@@ -0,0 +1,2104 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test cases for cgo.
+// Both the import "C" prologue and the main file are sorted by issue number.
+// This file contains C definitions (not just declarations)
+// and so it must NOT contain any //export directives on Go functions.
+// See testx.go for exports.
+
+package cgotest
+
+/*
+#include <complex.h>
+#include <math.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <errno.h>
+#cgo LDFLAGS: -lm
+
+#ifndef WIN32
+#include <pthread.h>
+#include <signal.h>
+#endif
+
+// alignment tests
+
+typedef unsigned char Uint8;
+typedef unsigned short Uint16;
+
+typedef enum {
+ MOD1 = 0x0000,
+ MODX = 0x8000
+} SDLMod;
+
+typedef enum {
+ A1 = 1,
+ B1 = 322,
+ SDLK_LAST
+} SDLKey;
+
+typedef struct SDL_keysym {
+	Uint8 scancode;
+	SDLKey sym;
+	SDLMod mod;
+	Uint16 unicode;
+} SDL_keysym;
+
+typedef struct SDL_KeyboardEvent {
+	Uint8 typ;
+	Uint8 which;
+	Uint8 state;
+	SDL_keysym keysym;
+} SDL_KeyboardEvent;
+
+void makeEvent(SDL_KeyboardEvent *event) {
+ unsigned char *p;
+ int i;
+
+ p = (unsigned char*)event;
+ for (i=0; i<sizeof *event; i++) {
+   p[i] = i;
+ }
+}
+
+int same(SDL_KeyboardEvent* e, Uint8 typ, Uint8 which, Uint8 state, Uint8 scan, SDLKey sym, SDLMod mod, Uint16 uni) {
+  return e->typ == typ && e->which == which && e->state == state && e->keysym.scancode == scan && e->keysym.sym == sym && e->keysym.mod == mod && e->keysym.unicode == uni;
+}
+
+void cTest(SDL_KeyboardEvent *event) {
+ printf("C: %#x %#x %#x %#x %#x %#x %#x\n", event->typ, event->which, event->state,
+   event->keysym.scancode, event->keysym.sym, event->keysym.mod, event->keysym.unicode);
+ fflush(stdout);
+}
+
+// api
+
+const char *greeting = "hello, world";
+
+// basic test cases
+
+#define SHIFT(x, y)  ((x)<<(y))
+#define KILO SHIFT(1, 10)
+#define UINT32VAL 0xc008427bU
+
+enum E {
+	Enum1 = 1,
+	Enum2 = 2,
+};
+
+typedef unsigned char cgo_uuid_t[20];
+
+void uuid_generate(cgo_uuid_t x) {
+	x[0] = 0;
+}
+
+struct S {
+	int x;
+};
+
+const char *cstr = "abcefghijklmnopqrstuvwxyzABCEFGHIJKLMNOPQRSTUVWXYZ1234567890";
+
+extern enum E myConstFunc(struct S* const ctx, int const id, struct S **const filter);
+
+enum E myConstFunc(struct S *const ctx, int const id, struct S **const filter) { return 0; }
+
+int add(int x, int y) {
+	return x+y;
+};
+
+// complex alignment
+
+struct {
+	float x;
+	_Complex float y;
+} cplxAlign = { 3.14, 2.17 };
+
+// constants and pointer checking
+
+#define CheckConstVal 0
+
+typedef struct {
+	int *p;
+} CheckConstStruct;
+
+static void CheckConstFunc(CheckConstStruct *p, int e) {}
+
+// duplicate symbol
+
+int base_symbol = 0;
+#define alias_one base_symbol
+#define alias_two base_symbol
+
+// function pointer variables
+
+typedef int (*intFunc) ();
+
+int
+bridge_int_func(intFunc f)
+{
+	return f();
+}
+
+int fortytwo()
+{
+	return 42;
+}
+
+// issue 1222
+typedef union {
+	long align;
+} xxpthread_mutex_t;
+struct ibv_async_event {
+	union {
+		int x;
+	} element;
+};
+struct ibv_context {
+	xxpthread_mutex_t mutex;
+};
+
+// issue 1635
+// Mac OS X's gcc will generate scattered relocation 2/1 for
+// this function on Darwin/386, and 8l couldn't handle it.
+// this example is in issue 1635
+void scatter() {
+	void *p = scatter;
+	printf("scatter = %p\n", p);
+}
+
+// Adding this explicit extern declaration makes this a test for
+// https://gcc.gnu.org/PR68072 aka https://golang.org/issue/13344 .
+// It used to cause a cgo error when building with GCC 6.
+extern int hola;
+
+// this example is in issue 3253
+int hola = 0;
+int testHola() { return hola; }
+
+// issue 3250
+#ifdef WIN32
+void testSendSIG() {}
+#else
+static void *thread(void *p) {
+	const int M = 100;
+	int i;
+	(void)p;
+	for (i = 0; i < M; i++) {
+		pthread_kill(pthread_self(), SIGCHLD);
+		usleep(rand() % 20 + 5);
+	}
+	return NULL;
+}
+void testSendSIG() {
+	const int N = 20;
+	int i;
+	pthread_t tid[N];
+	for (i = 0; i < N; i++) {
+		usleep(rand() % 200 + 100);
+		pthread_create(&tid[i], 0, thread, NULL);
+	}
+	for (i = 0; i < N; i++)
+		pthread_join(tid[i], 0);
+}
+#endif
+
+// issue 3261
+// libgcc on ARM might be compiled as thumb code, but our 5l
+// can't handle that, so we have to disable this test on arm.
+#ifdef __ARMEL__
+int vabs(int x) {
+	puts("testLibgcc is disabled on ARM because 5l cannot handle thumb library.");
+	return (x < 0) ? -x : x;
+}
+#elif defined(__arm64__) && defined(__clang__)
+int vabs(int x) {
+	puts("testLibgcc is disabled on ARM64 with clang due to lack of libgcc.");
+	return (x < 0) ? -x : x;
+}
+#else
+int __absvsi2(int); // dummy prototype for libgcc function
+// we shouldn't name the function abs, as gcc might use
+// the builtin one.
+int vabs(int x) { return __absvsi2(x); }
+#endif
+
+
+// issue 3729
+// access errno from void C function
+const char _expA = 0x42;
+const float _expB = 3.14159;
+const short _expC = 0x55aa;
+const int _expD = 0xdeadbeef;
+
+#ifdef WIN32
+void g(void) {}
+void g2(int x, char a, float b, short c, int d) {}
+#else
+
+void g(void) {
+	errno = E2BIG;
+}
+
+// try to pass some non-trivial arguments to function g2
+void g2(int x, char a, float b, short c, int d) {
+	if (a == _expA && b == _expB && c == _expC && d == _expD)
+		errno = x;
+	else
+		errno = -1;
+}
+#endif
+
+// issue 3945
+// Test that cgo reserves enough stack space during cgo call.
+// See https://golang.org/issue/3945 for details.
+void say() {
+	printf("%s from C\n", "hello");
+}
+
+// issue 4054 part 1 - other half in testx.go
+
+typedef enum {
+	A = 0,
+	B,
+	C,
+	D,
+	E,
+	F,
+	G,
+	H,
+	II,
+	J,
+} issue4054a;
+
+// issue 4339
+// We've historically permitted #include <>, so test it here.  Issue 29333.
+#include <issue4339.h>
+
+// issue 4417
+// cmd/cgo: bool alignment/padding issue.
+// bool alignment is wrong and causing wrong arguments when calling functions.
+static int c_bool(bool a, bool b, int c, bool d, bool e)  {
+   return c;
+}
+
+// issue 4857
+#cgo CFLAGS: -Werror
+const struct { int a; } *issue4857() { return (void *)0; }
+
+// issue 5224
+// Test that the #cgo CFLAGS directive works,
+// with and without platform filters.
+#cgo CFLAGS: -DCOMMON_VALUE=123
+#cgo windows CFLAGS: -DIS_WINDOWS=1
+#cgo !windows CFLAGS: -DIS_WINDOWS=0
+int common = COMMON_VALUE;
+int is_windows = IS_WINDOWS;
+
+// issue 5227
+// linker incorrectly treats common symbols and
+// leaves them undefined.
+
+typedef struct {
+        int Count;
+} Fontinfo;
+
+Fontinfo SansTypeface;
+
+extern void init();
+
+Fontinfo loadfont() {
+        Fontinfo f = {0};
+        return f;
+}
+
+void init() {
+        SansTypeface = loadfont();
+}
+
+// issue 5242
+// Cgo incorrectly computed the alignment of structs
+// with no Go accessible fields as 0, and then panicked on
+// modulo-by-zero computations.
+typedef struct {
+} foo;
+
+typedef struct {
+	int x : 1;
+} bar;
+
+int issue5242(foo f, bar b) {
+	return 5242;
+}
+
+// issue 5337
+// Verify that we can withstand SIGPROF received on foreign threads
+
+#ifdef WIN32
+void test5337() {}
+#else
+static void *thread1(void *p) {
+	(void)p;
+	pthread_kill(pthread_self(), SIGPROF);
+	return NULL;
+}
+void test5337() {
+	pthread_t tid;
+	pthread_create(&tid, 0, thread1, NULL);
+	pthread_join(tid, 0);
+}
+#endif
+
+// issue 5603
+
+const long long issue5603exp = 0x12345678;
+long long issue5603foo0() { return issue5603exp; }
+long long issue5603foo1(void *p) { return issue5603exp; }
+long long issue5603foo2(void *p, void *q) { return issue5603exp; }
+long long issue5603foo3(void *p, void *q, void *r) { return issue5603exp; }
+long long issue5603foo4(void *p, void *q, void *r, void *s) { return issue5603exp; }
+
+// issue 5740
+
+int test5740a(void), test5740b(void);
+
+// issue 5986
+static void output5986()
+{
+    int current_row = 0, row_count = 0;
+    double sum_squares = 0;
+    double d;
+    do {
+        if (current_row == 10) {
+            current_row = 0;
+        }
+        ++row_count;
+    }
+    while (current_row++ != 1);
+    d =  sqrt(sum_squares / row_count);
+    printf("sqrt is: %g\n", d);
+}
+
+// issue 6128
+// Test handling of #defined names in clang.
+// NOTE: Must use hex, or else a shortcut for decimals
+// in cgo avoids trying to pass this to clang.
+#define X 0x1
+
+// issue 6472
+typedef struct
+{
+        struct
+        {
+            int x;
+        } y[16];
+} z;
+
+// issue 6612
+// Test new scheme for deciding whether C.name is an expression, type, constant.
+// Clang silences some warnings when the name is a #defined macro, so test those too
+// (even though we now use errors exclusively, not warnings).
+
+void myfunc(void) {}
+int myvar = 5;
+const char *mytext = "abcdef";
+typedef int mytype;
+enum {
+	myenum = 1234,
+};
+
+#define myfunc_def myfunc
+#define myvar_def myvar
+#define mytext_def mytext
+#define mytype_def mytype
+#define myenum_def myenum
+#define myint_def 12345
+#define myfloat_def 1.5
+#define mystring_def "hello"
+
+// issue 6907
+char* Issue6907CopyString(_GoString_ s) {
+	size_t n;
+	const char *p;
+	char *r;
+
+	n = _GoStringLen(s);
+	p = _GoStringPtr(s);
+	r = malloc(n + 1);
+	memmove(r, p, n);
+	r[n] = '\0';
+	return r;
+}
+
+// issue 7560
+typedef struct {
+	char x;
+	long y;
+} __attribute__((__packed__)) misaligned;
+
+int
+offset7560(void)
+{
+	return (uintptr_t)&((misaligned*)0)->y;
+}
+
+// issue 7786
+// No runtime test, just make sure that typedef and struct/union/class are interchangeable at compile time.
+
+struct test7786;
+typedef struct test7786 typedef_test7786;
+void f7786(struct test7786 *ctx) {}
+void g7786(typedef_test7786 *ctx) {}
+
+typedef struct body7786 typedef_body7786;
+struct body7786 { int x; };
+void b7786(struct body7786 *ctx) {}
+void c7786(typedef_body7786 *ctx) {}
+
+typedef union union7786 typedef_union7786;
+void u7786(union union7786 *ctx) {}
+void v7786(typedef_union7786 *ctx) {}
+
+// issue 8092
+// Test that linker defined symbols (e.g., text, data) don't
+// conflict with C symbols.
+char text[] = "text";
+char data[] = "data";
+char *ctext(void) { return text; }
+char *cdata(void) { return data; }
+
+// issue 8428
+// Cgo inconsistently translated zero size arrays.
+
+struct issue8428one {
+	char b;
+	char rest[];
+};
+
+struct issue8428two {
+	void *p;
+	char b;
+	char rest[0];
+	char pad;
+};
+
+struct issue8428three {
+	char w[1][2][3][0];
+	char x[2][3][0][1];
+	char y[3][0][1][2];
+	char z[0][1][2][3];
+};
+
+// issue 8331 part 1 - part 2 in testx.go
+// A typedef of an unnamed struct is the same struct when
+// #include'd twice.  No runtime test; just make sure it compiles.
+#include "issue8331.h"
+
+// issue 8368 and 8441
+// Recursive struct definitions didn't work.
+// No runtime test; just make sure it compiles.
+typedef struct one one;
+typedef struct two two;
+struct one {
+	two *x;
+};
+struct two {
+	one *x;
+};
+
+// issue 8811
+
+extern int issue8811Initialized;
+extern void issue8811Init();
+
+void issue8811Execute() {
+	if(!issue8811Initialized)
+		issue8811Init();
+}
+
+// issue 9557
+
+struct issue9557_t {
+  int a;
+} test9557bar = { 42 };
+struct issue9557_t *issue9557foo = &test9557bar;
+
+// issue 10303
+// Pointers passed to C were not marked as escaping (bug in cgo).
+
+typedef int *intptr;
+
+void setintstar(int *x) {
+	*x = 1;
+}
+
+void setintptr(intptr x) {
+	*x = 1;
+}
+
+void setvoidptr(void *x) {
+	*(int*)x = 1;
+}
+
+typedef struct Struct Struct;
+struct Struct {
+	int *P;
+};
+
+void setstruct(Struct s) {
+	*s.P = 1;
+}
+
+// issue 11925
+// Structs with zero-length trailing fields are now padded by the Go compiler.
+
+struct a11925 {
+	int i;
+	char a[0];
+	char b[0];
+};
+
+struct b11925 {
+	int i;
+	char a[0];
+	char b[];
+};
+
+// issue 12030
+void issue12030conv(char *buf, double x) {
+	sprintf(buf, "d=%g", x);
+}
+
+// issue 14838
+
+int check_cbytes(char *b, size_t l) {
+	int i;
+	for (i = 0; i < l; i++) {
+		if (b[i] != i) {
+			return 0;
+		}
+	}
+	return 1;
+}
+
+// issue 17065
+// Test that C symbols larger than a page play nicely with the race detector.
+int ii[65537];
+
+// issue 17537
+// The void* cast introduced by cgo to avoid problems
+// with const/volatile qualifiers breaks C preprocessor macros that
+// emulate functions.
+
+typedef struct {
+	int i;
+} S17537;
+
+int I17537(S17537 *p);
+
+#define I17537(p) ((p)->i)
+
+// Calling this function used to fail without the cast.
+const int F17537(const char **p) {
+	return **p;
+}
+
+// issue 17723
+// API compatibility checks
+
+typedef char *cstring_pointer;
+static void cstring_pointer_fun(cstring_pointer dummy) { }
+const char *api_hello = "hello!";
+
+// Calling this function used to trigger an error from the C compiler
+// (issue 18298).
+void F18298(const void *const *p) {
+}
+
+// Test that conversions between typedefs work as they used to.
+typedef const void *T18298_1;
+struct S18298 { int i; };
+typedef const struct S18298 *T18298_2;
+void G18298(T18298_1 t) {
+}
+
+// issue 18126
+// cgo check of void function returning errno.
+void Issue18126C(void **p) {}
+
+// issue 18720
+
+#define HELLO "hello"
+#define WORLD "world"
+#define HELLO_WORLD HELLO "\000" WORLD
+
+struct foo { char c; };
+#define SIZE_OF(x) sizeof(x)
+#define SIZE_OF_FOO SIZE_OF(struct foo)
+#define VAR1 VAR
+#define VAR var
+int var = 5;
+
+#define ADDR &var
+
+#define CALL fn()
+int fn(void) {
+	return ++var;
+}
+
+// issue 20129
+
+int issue20129 = 0;
+typedef void issue20129Void;
+issue20129Void issue20129Foo() {
+	issue20129 = 1;
+}
+typedef issue20129Void issue20129Void2;
+issue20129Void2 issue20129Bar() {
+	issue20129 = 2;
+}
+
+// issue 20369
+#define XUINT64_MAX        18446744073709551615ULL
+
+// issue 21668
+// Fail to guess the kind of the constant "x".
+// No runtime test; just make sure it compiles.
+const int x21668 = 42;
+
+// issue 21708
+#define CAST_TO_INT64 (int64_t)(-1)
+
+// issue 21809
+// Compile C `typedef` to go type aliases.
+
+typedef long MySigned_t;
+// tests alias-to-alias
+typedef MySigned_t MySigned2_t;
+long takes_long(long x) { return x * x; }
+MySigned_t takes_typedef(MySigned_t x) { return x * x; }
+
+// issue 22906
+
+// It's going to be hard to include a whole real JVM to test this.
+// So we'll simulate a really easy JVM using just the parts we need.
+// This is the relevant part of jni.h.
+
+struct _jobject;
+
+typedef struct _jobject *jobject;
+typedef jobject jclass;
+typedef jobject jthrowable;
+typedef jobject jstring;
+typedef jobject jarray;
+typedef jarray jbooleanArray;
+typedef jarray jbyteArray;
+typedef jarray jcharArray;
+typedef jarray jshortArray;
+typedef jarray jintArray;
+typedef jarray jlongArray;
+typedef jarray jfloatArray;
+typedef jarray jdoubleArray;
+typedef jarray jobjectArray;
+
+typedef jobject jweak;
+
+// Note: jvalue is already a non-pointer type due to it being a C union.
+
+// issue 22958
+
+typedef struct {
+	unsigned long long f8  : 8;
+	unsigned long long f16 : 16;
+	unsigned long long f24 : 24;
+	unsigned long long f32 : 32;
+	unsigned long long f40 : 40;
+	unsigned long long f48 : 48;
+	unsigned long long f56 : 56;
+	unsigned long long f64 : 64;
+} issue22958Type;
+
+// issue 23356
+int a(void) { return 5; };
+int r(void) { return 3; };
+
+// issue 23720
+typedef int *issue23720A;
+typedef const int *issue23720B;
+void issue23720F(issue23720B a) {}
+
+// issue 24206
+#if defined(__linux__) && defined(__x86_64__)
+#include <sys/mman.h>
+// Returns string with null byte at the last valid address
+char* dangerousString1() {
+	int pageSize = 4096;
+	char *data = mmap(0, 2 * pageSize, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, 0, 0);
+	mprotect(data + pageSize,pageSize,PROT_NONE);
+	int start = pageSize - 123 - 1; // last 123 bytes of first page + 1 null byte
+	int i = start;
+	for (; i < pageSize; i++) {
+	data[i] = 'x';
+	}
+	data[pageSize -1 ] = 0;
+	return data+start;
+}
+
+char* dangerousString2() {
+	int pageSize = 4096;
+	char *data = mmap(0, 3 * pageSize, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, 0, 0);
+	mprotect(data + 2 * pageSize,pageSize,PROT_NONE);
+	int start = pageSize - 123 - 1; // last 123 bytes of first page + 1 null byte
+	int i = start;
+	for (; i < 2 * pageSize; i++) {
+	data[i] = 'x';
+	}
+	data[2*pageSize -1 ] = 0;
+	return data+start;
+}
+#else
+char *dangerousString1() { return NULL; }
+char *dangerousString2() { return NULL; }
+#endif
+
+// issue 26066
+const unsigned long long int issue26066 = (const unsigned long long) -1;
+
+// issue 26517
+// Introduce two pointer types which are distinct, but have the same
+// base type. Make sure that both of those pointer types get resolved
+// correctly. Before the fix for 26517 if one of these pointer types
+// was resolved before the other one was processed, the second one
+// would never be resolved.
+// Before this issue was fixed this test failed on Windows,
+// where va_list expands to a named char* type.
+typedef va_list TypeOne;
+typedef char *TypeTwo;
+
+// issue 28540
+
+static void twoargs1(void *p, int n) {}
+static void *twoargs2() { return 0; }
+static int twoargs3(void * p) { return 0; }
+
+// issue 28545
+// Failed to add type conversion for negative constant.
+
+static void issue28545F(char **p, int n, complex double a) {}
+
+// issue 28772 part 1 - part 2 in testx.go
+// Failed to add type conversion for Go constant set to C constant.
+// No runtime test; just make sure it compiles.
+
+#define issue28772Constant 1
+
+// issue 28896
+// cgo was incorrectly adding padding after a packed struct.
+typedef struct {
+	void *f1;
+	uint32_t f2;
+} __attribute__((__packed__)) innerPacked;
+
+typedef struct {
+	innerPacked g1;
+	uint64_t g2;
+} outerPacked;
+
+typedef struct {
+	void *f1;
+	uint32_t f2;
+} innerUnpacked;
+
+typedef struct {
+	innerUnpacked g1;
+	uint64_t g2;
+} outerUnpacked;
+
+size_t offset(int x) {
+	switch (x) {
+	case 0:
+		return offsetof(innerPacked, f2);
+	case 1:
+		return offsetof(outerPacked, g2);
+	case 2:
+		return offsetof(innerUnpacked, f2);
+	case 3:
+		return offsetof(outerUnpacked, g2);
+	default:
+		abort();
+	}
+}
+
+// issue 29748
+
+typedef struct { char **p; } S29748;
+static int f29748(S29748 *p) { return 0; }
+
+// issue 29781
+// Error with newline inserted into constant expression.
+// Compilation test only, nothing to run.
+
+static void issue29781F(char **p, int n) {}
+#define ISSUE29781C 0
+
+// issue 31093
+static uint16_t issue31093F(uint16_t v) { return v; }
+
+// issue 32579
+typedef struct S32579 { unsigned char data[1]; } S32579;
+*/
+import "C"
+
+import (
+	"context"
+	"fmt"
+	"math"
+	"math/rand"
+	"os"
+	"os/signal"
+	"reflect"
+	"runtime"
+	"sync"
+	"syscall"
+	"testing"
+	"time"
+	"unsafe"
+)
+
+// alignment
+
+func testAlign(t *testing.T) {
+	var evt C.SDL_KeyboardEvent
+	C.makeEvent(&evt)
+	if C.same(&evt, evt.typ, evt.which, evt.state, evt.keysym.scancode, evt.keysym.sym, evt.keysym.mod, evt.keysym.unicode) == 0 {
+		t.Error("*** bad alignment")
+		C.cTest(&evt)
+		t.Errorf("Go: %#x %#x %#x %#x %#x %#x %#x\n",
+			evt.typ, evt.which, evt.state, evt.keysym.scancode,
+			evt.keysym.sym, evt.keysym.mod, evt.keysym.unicode)
+		t.Error(evt)
+	}
+}
+
+// api
+
+const greeting = "hello, world"
+
+type testPair struct {
+	Name      string
+	Got, Want interface{}
+}
+
+var testPairs = []testPair{
+	{"GoString", C.GoString(C.greeting), greeting},
+	{"GoStringN", C.GoStringN(C.greeting, 5), greeting[:5]},
+	{"GoBytes", C.GoBytes(unsafe.Pointer(C.greeting), 5), []byte(greeting[:5])},
+}
+
+func testHelpers(t *testing.T) {
+	for _, pair := range testPairs {
+		if !reflect.DeepEqual(pair.Got, pair.Want) {
+			t.Errorf("%s: got %#v, want %#v", pair.Name, pair.Got, pair.Want)
+		}
+	}
+}
+
+// basic test cases
+
+const EINVAL = C.EINVAL /* test #define */
+
+var KILO = C.KILO
+
+func uuidgen() {
+	var uuid C.cgo_uuid_t
+	C.uuid_generate(&uuid[0])
+}
+
+func Strtol(s string, base int) (int, error) {
+	p := C.CString(s)
+	n, err := C.strtol(p, nil, C.int(base))
+	C.free(unsafe.Pointer(p))
+	return int(n), err
+}
+
+func Atol(s string) int {
+	p := C.CString(s)
+	n := C.atol(p)
+	C.free(unsafe.Pointer(p))
+	return int(n)
+}
+
+func testConst(t *testing.T) {
+	C.myConstFunc(nil, 0, nil)
+}
+
+func testEnum(t *testing.T) {
+	if C.Enum1 != 1 || C.Enum2 != 2 {
+		t.Error("bad enum", C.Enum1, C.Enum2)
+	}
+}
+
+func testAtol(t *testing.T) {
+	l := Atol("123")
+	if l != 123 {
+		t.Error("Atol 123: ", l)
+	}
+}
+
+func testErrno(t *testing.T) {
+	p := C.CString("no-such-file")
+	m := C.CString("r")
+	f, err := C.fopen(p, m)
+	C.free(unsafe.Pointer(p))
+	C.free(unsafe.Pointer(m))
+	if err == nil {
+		C.fclose(f)
+		t.Fatalf("C.fopen: should fail")
+	}
+	if err != syscall.ENOENT {
+		t.Fatalf("C.fopen: unexpected error: %v", err)
+	}
+}
+
+func testMultipleAssign(t *testing.T) {
+	p := C.CString("234")
+	n, m := C.strtol(p, nil, 345), C.strtol(p, nil, 10)
+	if runtime.GOOS == "openbsd" {
+		// Bug in OpenBSD strtol(3) - base > 36 succeeds.
+		if (n != 0 && n != 239089) || m != 234 {
+			t.Fatal("Strtol x2: ", n, m)
+		}
+	} else if n != 0 || m != 234 {
+		t.Fatal("Strtol x2: ", n, m)
+	}
+	C.free(unsafe.Pointer(p))
+}
+
+var (
+	cuint  = (C.uint)(0)
+	culong C.ulong
+	cchar  C.char
+)
+
+type Context struct {
+	ctx *C.struct_ibv_context
+}
+
+func benchCgoCall(b *testing.B) {
+	const x = C.int(2)
+	const y = C.int(3)
+	for i := 0; i < b.N; i++ {
+		C.add(x, y)
+	}
+}
+
+var sinkString string
+
+func benchGoString(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		sinkString = C.GoString(C.cstr)
+	}
+	const want = "abcefghijklmnopqrstuvwxyzABCEFGHIJKLMNOPQRSTUVWXYZ1234567890"
+	if sinkString != want {
+		b.Fatalf("%q != %q", sinkString, want)
+	}
+}
+
+// Static (build-time) test that syntax traversal visits all operands of s[i:j:k].
+func sliceOperands(array [2000]int) {
+	_ = array[C.KILO:C.KILO:C.KILO] // no type error
+}
+
+// set in cgo_thread_lock.go init
+var testThreadLockFunc = func(*testing.T) {}
+
+// complex alignment
+
+func TestComplexAlign(t *testing.T) {
+	if C.cplxAlign.x != 3.14 {
+		t.Errorf("got %v, expected 3.14", C.cplxAlign.x)
+	}
+	if C.cplxAlign.y != 2.17 {
+		t.Errorf("got %v, expected 2.17", C.cplxAlign.y)
+	}
+}
+
+// constants and pointer checking
+
+func testCheckConst(t *testing.T) {
+	// The test is that this compiles successfully.
+	p := C.malloc(C.size_t(unsafe.Sizeof(C.int(0))))
+	defer C.free(p)
+	C.CheckConstFunc(&C.CheckConstStruct{(*C.int)(p)}, C.CheckConstVal)
+}
+
+// duplicate symbol
+
+func duplicateSymbols() {
+	fmt.Printf("%v %v %v\n", C.base_symbol, C.alias_one, C.alias_two)
+}
+
+// environment
+
+// This is really an os package test but here for convenience.
+func testSetEnv(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		// Go uses SetEnvironmentVariable on windows. However,
+		// C runtime takes a *copy* at process startup of the
+		// OS environment, and stores it in environ/envp.
+		// It is this copy that	getenv/putenv manipulate.
+		t.Logf("skipping test")
+		return
+	}
+	const key = "CGO_OS_TEST_KEY"
+	const val = "CGO_OS_TEST_VALUE"
+	os.Setenv(key, val)
+	keyc := C.CString(key)
+	defer C.free(unsafe.Pointer(keyc))
+	v := C.getenv(keyc)
+	if uintptr(unsafe.Pointer(v)) == 0 {
+		t.Fatal("getenv returned NULL")
+	}
+	vs := C.GoString(v)
+	if vs != val {
+		t.Fatalf("getenv() = %q; want %q", vs, val)
+	}
+}
+
+// function pointer variables
+
+func callBridge(f C.intFunc) int {
+	return int(C.bridge_int_func(f))
+}
+
+func callCBridge(f C.intFunc) C.int {
+	return C.bridge_int_func(f)
+}
+
+func testFpVar(t *testing.T) {
+	const expected = 42
+	f := C.intFunc(C.fortytwo)
+	res1 := C.bridge_int_func(f)
+	if r1 := int(res1); r1 != expected {
+		t.Errorf("got %d, want %d", r1, expected)
+	}
+	res2 := callCBridge(f)
+	if r2 := int(res2); r2 != expected {
+		t.Errorf("got %d, want %d", r2, expected)
+	}
+	r3 := callBridge(f)
+	if r3 != expected {
+		t.Errorf("got %d, want %d", r3, expected)
+	}
+}
+
+// issue 1222
+type AsyncEvent struct {
+	event C.struct_ibv_async_event
+}
+
+// issue 1635
+
+func test1635(t *testing.T) {
+	C.scatter()
+	if v := C.hola; v != 0 {
+		t.Fatalf("C.hola is %d, should be 0", v)
+	}
+	if v := C.testHola(); v != 0 {
+		t.Fatalf("C.testHola() is %d, should be 0", v)
+	}
+}
+
+// issue 2470
+
+func testUnsignedInt(t *testing.T) {
+	a := (int64)(C.UINT32VAL)
+	b := (int64)(0xc008427b)
+	if a != b {
+		t.Errorf("Incorrect unsigned int - got %x, want %x", a, b)
+	}
+}
+
+// issue 3250
+
+func test3250(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("not applicable on windows")
+	}
+
+	t.Skip("skipped, see golang.org/issue/5885")
+	var (
+		thres = 1
+		sig   = syscall_dot_SIGCHLD
+	)
+	type result struct {
+		n   int
+		sig os.Signal
+	}
+	var (
+		sigCh     = make(chan os.Signal, 10)
+		waitStart = make(chan struct{})
+		waitDone  = make(chan result)
+	)
+
+	signal.Notify(sigCh, sig)
+
+	go func() {
+		n := 0
+		alarm := time.After(time.Second * 3)
+		for {
+			select {
+			case <-waitStart:
+				waitStart = nil
+			case v := <-sigCh:
+				n++
+				if v != sig || n > thres {
+					waitDone <- result{n, v}
+					return
+				}
+			case <-alarm:
+				waitDone <- result{n, sig}
+				return
+			}
+		}
+	}()
+
+	waitStart <- struct{}{}
+	C.testSendSIG()
+	r := <-waitDone
+	if r.sig != sig {
+		t.Fatalf("received signal %v, but want %v", r.sig, sig)
+	}
+	t.Logf("got %d signals\n", r.n)
+	if r.n <= thres {
+		t.Fatalf("expected more than %d", thres)
+	}
+}
+
+// issue 3261
+
+func testLibgcc(t *testing.T) {
+	var table = []struct {
+		in, out C.int
+	}{
+		{0, 0},
+		{1, 1},
+		{-42, 42},
+		{1000300, 1000300},
+		{1 - 1<<31, 1<<31 - 1},
+	}
+	for _, v := range table {
+		if o := C.vabs(v.in); o != v.out {
+			t.Fatalf("abs(%d) got %d, should be %d", v.in, o, v.out)
+			return
+		}
+	}
+}
+
+// issue 3729
+
+func test3729(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("skipping on windows")
+	}
+
+	_, e := C.g()
+	if e != syscall.E2BIG {
+		t.Errorf("got %q, expect %q", e, syscall.E2BIG)
+	}
+	_, e = C.g2(C.EINVAL, C._expA, C._expB, C._expC, C._expD)
+	if e != syscall.EINVAL {
+		t.Errorf("got %q, expect %q", e, syscall.EINVAL)
+	}
+}
+
+// issue 3945
+
+func testPrintf(t *testing.T) {
+	C.say()
+}
+
+// issue 4054
+
+var issue4054a = []int{C.A, C.B, C.C, C.D, C.E, C.F, C.G, C.H, C.I, C.J}
+
+// issue 4339
+
+func test4339(t *testing.T) {
+	C.handle4339(&C.exported4339)
+}
+
+// issue 4417
+
+func testBoolAlign(t *testing.T) {
+	b := C.c_bool(true, true, 10, true, false)
+	if b != 10 {
+		t.Fatalf("found %d expected 10\n", b)
+	}
+	b = C.c_bool(true, true, 5, true, true)
+	if b != 5 {
+		t.Fatalf("found %d expected 5\n", b)
+	}
+	b = C.c_bool(true, true, 3, true, false)
+	if b != 3 {
+		t.Fatalf("found %d expected 3\n", b)
+	}
+	b = C.c_bool(false, false, 1, true, false)
+	if b != 1 {
+		t.Fatalf("found %d expected 1\n", b)
+	}
+	b = C.c_bool(false, true, 200, true, false)
+	if b != 200 {
+		t.Fatalf("found %d expected 200\n", b)
+	}
+}
+
+// issue 4857
+
+func test4857() {
+	_ = C.issue4857()
+}
+
+// issue 5224
+
+func testCflags(t *testing.T) {
+	is_windows := C.is_windows == 1
+	if is_windows != (runtime.GOOS == "windows") {
+		t.Errorf("is_windows: %v, runtime.GOOS: %s", is_windows, runtime.GOOS)
+	}
+	if C.common != 123 {
+		t.Errorf("common: %v (expected 123)", C.common)
+	}
+}
+
+// issue 5227
+
+func test5227(t *testing.T) {
+	C.init()
+}
+
+func selectfont() C.Fontinfo {
+	return C.SansTypeface
+}
+
+// issue 5242
+
+func test5242(t *testing.T) {
+	if got := C.issue5242(C.foo{}, C.bar{}); got != 5242 {
+		t.Errorf("got %v", got)
+	}
+}
+
+func test5603(t *testing.T) {
+	var x [5]int64
+	exp := int64(C.issue5603exp)
+	x[0] = int64(C.issue5603foo0())
+	x[1] = int64(C.issue5603foo1(nil))
+	x[2] = int64(C.issue5603foo2(nil, nil))
+	x[3] = int64(C.issue5603foo3(nil, nil, nil))
+	x[4] = int64(C.issue5603foo4(nil, nil, nil, nil))
+	for i, v := range x {
+		if v != exp {
+			t.Errorf("issue5603foo%d() returns %v, expected %v", i, v, exp)
+		}
+	}
+}
+
+// issue 5337
+
+func test5337(t *testing.T) {
+	C.test5337()
+}
+
+// issue 5740
+
+func test5740(t *testing.T) {
+	if v := C.test5740a() + C.test5740b(); v != 5 {
+		t.Errorf("expected 5, got %v", v)
+	}
+}
+
+// issue 5986
+
+func test5986(t *testing.T) {
+	C.output5986()
+}
+
+// issue 6128
+
+func test6128() {
+	// nothing to run, just make sure this compiles.
+	_ = C.X
+}
+
+// issue 6390
+
+func test6390(t *testing.T) {
+	p1 := C.malloc(1024)
+	if p1 == nil {
+		t.Fatalf("C.malloc(1024) returned nil")
+	}
+	p2 := C.malloc(0)
+	if p2 == nil {
+		t.Fatalf("C.malloc(0) returned nil")
+	}
+	C.free(p1)
+	C.free(p2)
+}
+
+func test6472() {
+	// nothing to run, just make sure this compiles
+	s := new(C.z)
+	println(s.y[0].x)
+}
+
+// issue 6506
+
+func test6506() {
+	// nothing to run, just make sure this compiles
+	var x C.size_t
+
+	C.calloc(x, x)
+	C.malloc(x)
+	C.realloc(nil, x)
+	C.memcpy(nil, nil, x)
+	C.memcmp(nil, nil, x)
+	C.memmove(nil, nil, x)
+	C.strncpy(nil, nil, x)
+	C.strncmp(nil, nil, x)
+	C.strncat(nil, nil, x)
+	x = C.strxfrm(nil, nil, x)
+	C.memchr(nil, 0, x)
+	x = C.strcspn(nil, nil)
+	x = C.strspn(nil, nil)
+	C.memset(nil, 0, x)
+	x = C.strlen(nil)
+	_ = x
+}
+
+// issue 6612
+
+func testNaming(t *testing.T) {
+	C.myfunc()
+	C.myfunc_def()
+	if v := C.myvar; v != 5 {
+		t.Errorf("C.myvar = %d, want 5", v)
+	}
+	if v := C.myvar_def; v != 5 {
+		t.Errorf("C.myvar_def = %d, want 5", v)
+	}
+	if s := C.GoString(C.mytext); s != "abcdef" {
+		t.Errorf("C.mytext = %q, want %q", s, "abcdef")
+	}
+	if s := C.GoString(C.mytext_def); s != "abcdef" {
+		t.Errorf("C.mytext_def = %q, want %q", s, "abcdef")
+	}
+	if c := C.myenum; c != 1234 {
+		t.Errorf("C.myenum = %v, want 1234", c)
+	}
+	if c := C.myenum_def; c != 1234 {
+		t.Errorf("C.myenum_def = %v, want 1234", c)
+	}
+	{
+		const c = C.myenum
+		if c != 1234 {
+			t.Errorf("C.myenum as const = %v, want 1234", c)
+		}
+	}
+	{
+		const c = C.myenum_def
+		if c != 1234 {
+			t.Errorf("C.myenum as const = %v, want 1234", c)
+		}
+	}
+	if c := C.myint_def; c != 12345 {
+		t.Errorf("C.myint_def = %v, want 12345", c)
+	}
+	{
+		const c = C.myint_def
+		if c != 12345 {
+			t.Errorf("C.myint as const = %v, want 12345", c)
+		}
+	}
+
+	if c := C.myfloat_def; c != 1.5 {
+		t.Errorf("C.myint_def = %v, want 1.5", c)
+	}
+	{
+		const c = C.myfloat_def
+		if c != 1.5 {
+			t.Errorf("C.myint as const = %v, want 1.5", c)
+		}
+	}
+
+	if s := C.mystring_def; s != "hello" {
+		t.Errorf("C.mystring_def = %q, want %q", s, "hello")
+	}
+}
+
+// issue 6907
+
+func test6907(t *testing.T) {
+	want := "yarn"
+	if got := C.GoString(C.Issue6907CopyString(want)); got != want {
+		t.Errorf("C.GoString(C.Issue6907CopyString(%q)) == %q, want %q", want, got, want)
+	}
+}
+
+// issue 7560
+
+func test7560(t *testing.T) {
+	// some mingw don't implement __packed__ correctly.
+	if C.offset7560() != 1 {
+		t.Skip("C compiler did not pack struct")
+	}
+
+	// C.misaligned should have x but then a padding field to get to the end of the struct.
+	// There should not be a field named 'y'.
+	var v C.misaligned
+	rt := reflect.TypeOf(&v).Elem()
+	if rt.NumField() != 2 || rt.Field(0).Name != "x" || rt.Field(1).Name != "_" {
+		t.Errorf("unexpected fields in C.misaligned:\n")
+		for i := 0; i < rt.NumField(); i++ {
+			t.Logf("%+v\n", rt.Field(i))
+		}
+	}
+}
+
+// issue 7786
+
+func f() {
+	var x1 *C.typedef_test7786
+	var x2 *C.struct_test7786
+	x1 = x2
+	x2 = x1
+	C.f7786(x1)
+	C.f7786(x2)
+	C.g7786(x1)
+	C.g7786(x2)
+
+	var b1 *C.typedef_body7786
+	var b2 *C.struct_body7786
+	b1 = b2
+	b2 = b1
+	C.b7786(b1)
+	C.b7786(b2)
+	C.c7786(b1)
+	C.c7786(b2)
+
+	var u1 *C.typedef_union7786
+	var u2 *C.union_union7786
+	u1 = u2
+	u2 = u1
+	C.u7786(u1)
+	C.u7786(u2)
+	C.v7786(u1)
+	C.v7786(u2)
+}
+
+// issue 8092
+
+func test8092(t *testing.T) {
+	tests := []struct {
+		s    string
+		a, b *C.char
+	}{
+		{"text", &C.text[0], C.ctext()},
+		{"data", &C.data[0], C.cdata()},
+	}
+	for _, test := range tests {
+		if test.a != test.b {
+			t.Errorf("%s: pointer mismatch: %v != %v", test.s, test.a, test.b)
+		}
+		if got := C.GoString(test.a); got != test.s {
+			t.Errorf("%s: points at %#v, want %#v", test.s, got, test.s)
+		}
+	}
+}
+
+// issues 8368 and 8441
+
+func issue8368(one *C.struct_one, two *C.struct_two) {
+}
+
+func issue8441(one *C.one, two *C.two) {
+	issue8441(two.x, one.x)
+}
+
+// issue 8428
+
+var _ = C.struct_issue8428one{
+	b: C.char(0),
+	// The trailing rest field is not available in cgo.
+	// See issue 11925.
+	// rest: [0]C.char{},
+}
+
+var _ = C.struct_issue8428two{
+	p:    unsafe.Pointer(nil),
+	b:    C.char(0),
+	rest: [0]C.char{},
+}
+
+var _ = C.struct_issue8428three{
+	w: [1][2][3][0]C.char{},
+	x: [2][3][0][1]C.char{},
+	y: [3][0][1][2]C.char{},
+	z: [0][1][2][3]C.char{},
+}
+
+// issue 8811
+
+func test8811(t *testing.T) {
+	C.issue8811Execute()
+}
+
+// issue 9557
+
+func test9557(t *testing.T) {
+	// implicitly dereference a Go variable
+	foo := C.issue9557foo
+	if v := foo.a; v != 42 {
+		t.Fatalf("foo.a expected 42, but got %d", v)
+	}
+
+	// explicitly dereference a C variable
+	if v := (*C.issue9557foo).a; v != 42 {
+		t.Fatalf("(*C.issue9557foo).a expected 42, but is %d", v)
+	}
+
+	// implicitly dereference a C variable
+	if v := C.issue9557foo.a; v != 42 {
+		t.Fatalf("C.issue9557foo.a expected 42, but is %d", v)
+	}
+}
+
+// issue 8331 part 1
+
+func issue8331a() C.issue8331 {
+	return issue8331Var
+}
+
+// issue 10303
+
+func test10303(t *testing.T, n int) {
+	if runtime.Compiler == "gccgo" {
+		t.Skip("gccgo permits C pointers on the stack")
+	}
+
+	// Run at a few different stack depths just to avoid an unlucky pass
+	// due to variables ending up on different pages.
+	if n > 0 {
+		test10303(t, n-1)
+	}
+	if t.Failed() {
+		return
+	}
+	var x, y, z, v, si C.int
+	var s C.Struct
+	C.setintstar(&x)
+	C.setintptr(&y)
+	C.setvoidptr(unsafe.Pointer(&v))
+	s.P = &si
+	C.setstruct(s)
+
+	if uintptr(unsafe.Pointer(&x))&^0xfff == uintptr(unsafe.Pointer(&z))&^0xfff {
+		t.Error("C int* argument on stack")
+	}
+	if uintptr(unsafe.Pointer(&y))&^0xfff == uintptr(unsafe.Pointer(&z))&^0xfff {
+		t.Error("C intptr argument on stack")
+	}
+	if uintptr(unsafe.Pointer(&v))&^0xfff == uintptr(unsafe.Pointer(&z))&^0xfff {
+		t.Error("C void* argument on stack")
+	}
+	if uintptr(unsafe.Pointer(&si))&^0xfff == uintptr(unsafe.Pointer(&z))&^0xfff {
+		t.Error("C struct field pointer on stack")
+	}
+}
+
+// issue 11925
+
+func test11925(t *testing.T) {
+	if C.sizeof_struct_a11925 != unsafe.Sizeof(C.struct_a11925{}) {
+		t.Errorf("size of a changed: C %d, Go %d", C.sizeof_struct_a11925, unsafe.Sizeof(C.struct_a11925{}))
+	}
+	if C.sizeof_struct_b11925 != unsafe.Sizeof(C.struct_b11925{}) {
+		t.Errorf("size of b changed: C %d, Go %d", C.sizeof_struct_b11925, unsafe.Sizeof(C.struct_b11925{}))
+	}
+}
+
+// issue 12030
+
+func test12030(t *testing.T) {
+	buf := (*C.char)(C.malloc(256))
+	defer C.free(unsafe.Pointer(buf))
+	for _, f := range []float64{1.0, 2.0, 3.14} {
+		C.issue12030conv(buf, C.double(f))
+		got := C.GoString(buf)
+		if want := fmt.Sprintf("d=%g", f); got != want {
+			t.Fatalf("C.sprintf failed for %g: %q != %q", f, got, want)
+		}
+	}
+}
+
+// issue 13402
+
+var _ C.complexfloat
+var _ C.complexdouble
+
+// issue 13930
+// Test that cgo's multiple-value special form for
+// C function calls works in variable declaration statements.
+
+var _, _ = C.abs(0)
+
+// issue 14838
+
+func test14838(t *testing.T) {
+	data := []byte{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
+	cData := C.CBytes(data)
+	defer C.free(cData)
+
+	if C.check_cbytes((*C.char)(cData), C.size_t(len(data))) == 0 {
+		t.Fatalf("mismatched data: expected %v, got %v", data, (*(*[10]byte)(unsafe.Pointer(cData)))[:])
+	}
+}
+
+// issue 17065
+
+var sink C.int
+
+func test17065(t *testing.T) {
+	if runtime.GOOS == "darwin" {
+		t.Skip("broken on darwin; issue 17065")
+	}
+	for i := range C.ii {
+		sink = C.ii[i]
+	}
+}
+
+// issue 17537
+
+func test17537(t *testing.T) {
+	v := C.S17537{i: 17537}
+	if got, want := C.I17537(&v), C.int(17537); got != want {
+		t.Errorf("got %d, want %d", got, want)
+	}
+
+	p := (*C.char)(C.malloc(1))
+	*p = 17
+	if got, want := C.F17537(&p), C.int(17); got != want {
+		t.Errorf("got %d, want %d", got, want)
+	}
+
+	C.F18298(nil)
+	var v18298 C.T18298_2
+	C.G18298(C.T18298_1(v18298))
+}
+
+// issue 17723
+
+func testAPI() {
+	var cs *C.char
+	cs = C.CString("hello")
+	defer C.free(unsafe.Pointer(cs))
+	var s string
+	s = C.GoString((*C.char)(C.api_hello))
+	s = C.GoStringN((*C.char)(C.api_hello), C.int(6))
+	var b []byte
+	b = C.GoBytes(unsafe.Pointer(C.api_hello), C.int(6))
+	_, _ = s, b
+	C.cstring_pointer_fun(nil)
+}
+
+// issue 18126
+
+func test18126(t *testing.T) {
+	p := C.malloc(1)
+	_, err := C.Issue18126C(&p)
+	C.free(p)
+	_ = err
+}
+
+// issue 18720
+
+func test18720(t *testing.T) {
+	if got, want := C.HELLO_WORLD, "hello\000world"; got != want {
+		t.Errorf("C.HELLO_WORLD == %q, expected %q", got, want)
+	}
+
+	if got, want := C.VAR1, C.int(5); got != want {
+		t.Errorf("C.VAR1 == %v, expected %v", got, want)
+	}
+
+	if got, want := *C.ADDR, C.int(5); got != want {
+		t.Errorf("*C.ADDR == %v, expected %v", got, want)
+	}
+
+	if got, want := C.CALL, C.int(6); got != want {
+		t.Errorf("C.CALL == %v, expected %v", got, want)
+	}
+
+	if got, want := C.CALL, C.int(7); got != want {
+		t.Errorf("C.CALL == %v, expected %v", got, want)
+	}
+
+	// Issue 20125.
+	if got, want := C.SIZE_OF_FOO, 1; got != want {
+		t.Errorf("C.SIZE_OF_FOO == %v, expected %v", got, want)
+	}
+}
+
+// issue 20129
+
+func test20129(t *testing.T) {
+	if C.issue20129 != 0 {
+		t.Fatal("test is broken")
+	}
+	C.issue20129Foo()
+	if C.issue20129 != 1 {
+		t.Errorf("got %v but expected %v", C.issue20129, 1)
+	}
+	C.issue20129Bar()
+	if C.issue20129 != 2 {
+		t.Errorf("got %v but expected %v", C.issue20129, 2)
+	}
+}
+
+// issue 20369
+
+func test20369(t *testing.T) {
+	if C.XUINT64_MAX != math.MaxUint64 {
+		t.Fatalf("got %v, want %v", uint64(C.XUINT64_MAX), uint64(math.MaxUint64))
+	}
+}
+
+// issue 21668
+
+var issue21668_X = C.x21668
+
+// issue 21708
+
+func test21708(t *testing.T) {
+	if got, want := C.CAST_TO_INT64, -1; got != want {
+		t.Errorf("C.CAST_TO_INT64 == %v, expected %v", got, want)
+	}
+}
+
+// issue 21809
+
+func test21809(t *testing.T) {
+	longVar := C.long(3)
+	typedefVar := C.MySigned_t(4)
+	typedefTypedefVar := C.MySigned2_t(5)
+
+	// all three should be considered identical to `long`
+	if ret := C.takes_long(longVar); ret != 9 {
+		t.Errorf("got %v but expected %v", ret, 9)
+	}
+	if ret := C.takes_long(typedefVar); ret != 16 {
+		t.Errorf("got %v but expected %v", ret, 16)
+	}
+	if ret := C.takes_long(typedefTypedefVar); ret != 25 {
+		t.Errorf("got %v but expected %v", ret, 25)
+	}
+
+	// They should also be identical to the typedef'd type
+	if ret := C.takes_typedef(longVar); ret != 9 {
+		t.Errorf("got %v but expected %v", ret, 9)
+	}
+	if ret := C.takes_typedef(typedefVar); ret != 16 {
+		t.Errorf("got %v but expected %v", ret, 16)
+	}
+	if ret := C.takes_typedef(typedefTypedefVar); ret != 25 {
+		t.Errorf("got %v but expected %v", ret, 25)
+	}
+}
+
+// issue 22906
+
+func test22906(t *testing.T) {
+	var x1 C.jobject = 0 // Note: 0, not nil. That makes sure we use uintptr for these types.
+	_ = x1
+	var x2 C.jclass = 0
+	_ = x2
+	var x3 C.jthrowable = 0
+	_ = x3
+	var x4 C.jstring = 0
+	_ = x4
+	var x5 C.jarray = 0
+	_ = x5
+	var x6 C.jbooleanArray = 0
+	_ = x6
+	var x7 C.jbyteArray = 0
+	_ = x7
+	var x8 C.jcharArray = 0
+	_ = x8
+	var x9 C.jshortArray = 0
+	_ = x9
+	var x10 C.jintArray = 0
+	_ = x10
+	var x11 C.jlongArray = 0
+	_ = x11
+	var x12 C.jfloatArray = 0
+	_ = x12
+	var x13 C.jdoubleArray = 0
+	_ = x13
+	var x14 C.jobjectArray = 0
+	_ = x14
+	var x15 C.jweak = 0
+	_ = x15
+}
+
+// issue 22958
+// Nothing to run, just make sure this compiles.
+var Vissue22958 C.issue22958Type
+
+func test23356(t *testing.T) {
+	if got, want := C.a(), C.int(5); got != want {
+		t.Errorf("C.a() == %v, expected %v", got, want)
+	}
+	if got, want := C.r(), C.int(3); got != want {
+		t.Errorf("C.r() == %v, expected %v", got, want)
+	}
+}
+
+// issue 23720
+
+func Issue23720F() {
+	var x C.issue23720A
+	C.issue23720F(x)
+}
+
+// issue 24206
+
+func test24206(t *testing.T) {
+	if runtime.GOOS != "linux" || runtime.GOARCH != "amd64" {
+		t.Skipf("skipping on %s/%s", runtime.GOOS, runtime.GOARCH)
+	}
+
+	if l := len(C.GoString(C.dangerousString1())); l != 123 {
+		t.Errorf("Incorrect string length - got %d, want 123", l)
+	}
+	if l := len(C.GoString(C.dangerousString2())); l != 4096+123 {
+		t.Errorf("Incorrect string length - got %d, want %d", l, 4096+123)
+	}
+}
+
+// issue 25143
+
+func issue25143sum(ns ...C.int) C.int {
+	total := C.int(0)
+	for _, n := range ns {
+		total += n
+	}
+	return total
+}
+
+func test25143(t *testing.T) {
+	if got, want := issue25143sum(1, 2, 3), C.int(6); got != want {
+		t.Errorf("issue25143sum(1, 2, 3) == %v, expected %v", got, want)
+	}
+}
+
+// issue 26066
+// Wrong type of constant with GCC 8 and newer.
+
+func test26066(t *testing.T) {
+	var i = int64(C.issue26066)
+	if i != -1 {
+		t.Errorf("got %d, want -1", i)
+	}
+}
+
+// issue 26517
+var a C.TypeOne
+var b C.TypeTwo
+
+// issue 27660
+// Stress the interaction between the race detector and cgo in an
+// attempt to reproduce the memory corruption described in #27660.
+// The bug was very timing sensitive; at the time of writing this
+// test would only trigger the bug about once out of every five runs.
+
+func test27660(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	ints := make([]int, 100)
+	locks := make([]sync.Mutex, 100)
+	// Slowly create threads so that ThreadSanitizer is forced to
+	// frequently resize its SyncClocks.
+	for i := 0; i < 100; i++ {
+		go func() {
+			for ctx.Err() == nil {
+				// Sleep in C for long enough that it is likely that the runtime
+				// will retake this goroutine's currently wired P.
+				C.usleep(1000 /* 1ms */)
+				runtime.Gosched() // avoid starvation (see #28701)
+			}
+		}()
+		go func() {
+			// Trigger lots of synchronization and memory reads/writes to
+			// increase the likelihood that the race described in #27660
+			// results in corruption of ThreadSanitizer's internal state
+			// and thus an assertion failure or segfault.
+			i := 0
+			for ctx.Err() == nil {
+				j := rand.Intn(100)
+				locks[j].Lock()
+				ints[j]++
+				locks[j].Unlock()
+				// Avoid making the loop unpreemptible
+				// for gccgo.
+				if i%0x1000000 == 0 {
+					runtime.Gosched()
+				}
+				i++
+			}
+		}()
+		time.Sleep(time.Millisecond)
+	}
+}
+
+// issue 28540
+
+func twoargsF() {
+	v := []string{}
+	C.twoargs1(C.twoargs2(), C.twoargs3(unsafe.Pointer(&v)))
+}
+
+// issue 28545
+
+func issue28545G(p **C.char) {
+	C.issue28545F(p, -1, (0))
+	C.issue28545F(p, 2+3, complex(1, 1))
+	C.issue28545F(p, issue28772Constant, issue28772Constant2)
+}
+
+// issue 28772 part 1 - part 2 in testx.go
+
+const issue28772Constant = C.issue28772Constant
+
+// issue 28896
+
+func offset(i int) uintptr {
+	var pi C.innerPacked
+	var po C.outerPacked
+	var ui C.innerUnpacked
+	var uo C.outerUnpacked
+	switch i {
+	case 0:
+		return unsafe.Offsetof(pi.f2)
+	case 1:
+		return unsafe.Offsetof(po.g2)
+	case 2:
+		return unsafe.Offsetof(ui.f2)
+	case 3:
+		return unsafe.Offsetof(uo.g2)
+	default:
+		panic("can't happen")
+	}
+}
+
+func test28896(t *testing.T) {
+	for i := 0; i < 4; i++ {
+		c := uintptr(C.offset(C.int(i)))
+		g := offset(i)
+		if c != g {
+			t.Errorf("%d: C: %d != Go %d", i, c, g)
+		}
+	}
+}
+
+// issue 29383
+// cgo's /*line*/ comments failed when inserted after '/',
+// because the result looked like a "//" comment.
+// No runtime test; just make sure it compiles.
+
+func Issue29383(n, size uint) int {
+	if ^C.size_t(0)/C.size_t(n) < C.size_t(size) {
+		return 0
+	}
+	return 0
+}
+
+// issue 29748
+// Error handling a struct initializer that requires pointer checking.
+// Compilation test only, nothing to run.
+
+var Vissue29748 = C.f29748(&C.S29748{
+	nil,
+})
+
+func Fissue299748() {
+	C.f29748(&C.S29748{
+		nil,
+	})
+}
+
+// issue 29781
+
+var issue29781X struct{ X int }
+
+func issue29781F(...int) int { return 0 }
+
+func issue29781G() {
+	var p *C.char
+	C.issue29781F(&p, C.ISSUE29781C+1)
+	C.issue29781F(nil, (C.int)(
+		0))
+	C.issue29781F(&p, (C.int)(0))
+	C.issue29781F(&p, (C.int)(
+		0))
+	C.issue29781F(&p, (C.int)(issue29781X.
+		X))
+}
+
+// issue 30065
+
+func test30065(t *testing.T) {
+	var a [256]byte
+	b := []byte("a")
+	C.memcpy(unsafe.Pointer(&a), unsafe.Pointer(&b[0]), 1)
+	if a[0] != 'a' {
+		t.Errorf("&a failed: got %c, want %c", a[0], 'a')
+	}
+
+	b = []byte("b")
+	C.memcpy(unsafe.Pointer(&a[0]), unsafe.Pointer(&b[0]), 1)
+	if a[0] != 'b' {
+		t.Errorf("&a[0] failed: got %c, want %c", a[0], 'b')
+	}
+
+	d := make([]byte, 256)
+	b = []byte("c")
+	C.memcpy(unsafe.Pointer(&d[0]), unsafe.Pointer(&b[0]), 1)
+	if d[0] != 'c' {
+		t.Errorf("&d[0] failed: got %c, want %c", d[0], 'c')
+	}
+}
+
+// issue 31093
+// No runtime test; just make sure it compiles.
+
+func Issue31093() {
+	C.issue31093F(C.ushort(0))
+}
+
+// issue 32579
+
+func test32579(t *testing.T) {
+	var s [1]C.struct_S32579
+	C.memset(unsafe.Pointer(&s[0].data[0]), 1, 1)
+	if s[0].data[0] != 1 {
+		t.Errorf("&s[0].data[0] failed: got %d, want %d", s[0].data[0], 1)
+	}
+}
diff --git a/libgo/misc/cgo/test/test22906.go b/libgo/misc/cgo/test/test22906.go
deleted file mode 100644
index 02bae9cfa7d..00000000000
--- a/libgo/misc/cgo/test/test22906.go
+++ /dev/null
@@ -1,74 +0,0 @@
-// Copyright 2017 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build cgo
-
-package cgotest
-
-/*
-
-// It's going to be hard to include a whole real JVM to test this.
-// So we'll simulate a really easy JVM using just the parts we need.
-
-// This is the relevant part of jni.h.
-
-struct _jobject;
-
-typedef struct _jobject *jobject;
-typedef jobject jclass;
-typedef jobject jthrowable;
-typedef jobject jstring;
-typedef jobject jarray;
-typedef jarray jbooleanArray;
-typedef jarray jbyteArray;
-typedef jarray jcharArray;
-typedef jarray jshortArray;
-typedef jarray jintArray;
-typedef jarray jlongArray;
-typedef jarray jfloatArray;
-typedef jarray jdoubleArray;
-typedef jarray jobjectArray;
-
-typedef jobject jweak;
-
-// Note: jvalue is already a non-pointer type due to it being a C union.
-
-*/
-import "C"
-import (
-	"testing"
-)
-
-func test22906(t *testing.T) {
-	var x1 C.jobject = 0 // Note: 0, not nil. That makes sure we use uintptr for these types.
-	_ = x1
-	var x2 C.jclass = 0
-	_ = x2
-	var x3 C.jthrowable = 0
-	_ = x3
-	var x4 C.jstring = 0
-	_ = x4
-	var x5 C.jarray = 0
-	_ = x5
-	var x6 C.jbooleanArray = 0
-	_ = x6
-	var x7 C.jbyteArray = 0
-	_ = x7
-	var x8 C.jcharArray = 0
-	_ = x8
-	var x9 C.jshortArray = 0
-	_ = x9
-	var x10 C.jintArray = 0
-	_ = x10
-	var x11 C.jlongArray = 0
-	_ = x11
-	var x12 C.jfloatArray = 0
-	_ = x12
-	var x13 C.jdoubleArray = 0
-	_ = x13
-	var x14 C.jobjectArray = 0
-	_ = x14
-	var x15 C.jweak = 0
-	_ = x15
-}
diff --git a/libgo/misc/cgo/test/test27660.go b/libgo/misc/cgo/test/test27660.go
deleted file mode 100644
index 0345aa7312b..00000000000
--- a/libgo/misc/cgo/test/test27660.go
+++ /dev/null
@@ -1,61 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Stress the interaction between the race detector and cgo in an
-// attempt to reproduce the memory corruption described in #27660.
-// The bug was very timing sensitive; at the time of writing this
-// test would only trigger the bug about once out of every five runs.
-
-package cgotest
-
-// #include <unistd.h>
-import "C"
-
-import (
-	"context"
-	"math/rand"
-	"runtime"
-	"sync"
-	"testing"
-	"time"
-)
-
-func test27660(t *testing.T) {
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	ints := make([]int, 100)
-	locks := make([]sync.Mutex, 100)
-	// Slowly create threads so that ThreadSanitizer is forced to
-	// frequently resize its SyncClocks.
-	for i := 0; i < 100; i++ {
-		go func() {
-			for ctx.Err() == nil {
-				// Sleep in C for long enough that it is likely that the runtime
-				// will retake this goroutine's currently wired P.
-				C.usleep(1000 /* 1ms */)
-				runtime.Gosched() // avoid starvation (see #28701)
-			}
-		}()
-		go func() {
-			// Trigger lots of synchronization and memory reads/writes to
-			// increase the likelihood that the race described in #27660
-			// results in corruption of ThreadSanitizer's internal state
-			// and thus an assertion failure or segfault.
-			i := 0
-			for ctx.Err() == nil {
-				j := rand.Intn(100)
-				locks[j].Lock()
-				ints[j]++
-				locks[j].Unlock()
-				// Avoid making the loop unpreemptible
-				// for gccgo.
-				if i%0x1000000 == 0 {
-					runtime.Gosched()
-				}
-				i++
-			}
-		}()
-		time.Sleep(time.Millisecond)
-	}
-}
diff --git a/libgo/misc/cgo/test/test_unix.go b/libgo/misc/cgo/test/test_unix.go
new file mode 100644
index 00000000000..4a234469dbc
--- /dev/null
+++ b/libgo/misc/cgo/test/test_unix.go
@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !windows
+
+package cgotest
+
+import "syscall"
+
+var syscall_dot_SIGCHLD = syscall.SIGCHLD
diff --git a/libgo/misc/cgo/test/issue13402.go b/libgo/misc/cgo/test/test_windows.go
index 3af24c2d3c2..7bfb33a83c3 100644
--- a/libgo/misc/cgo/test/issue13402.go
+++ b/libgo/misc/cgo/test/test_windows.go
@@ -1,10 +1,9 @@
-// Copyright 2015 The Go Authors. All rights reserved.
+// Copyright 2019 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
 package cgotest
 
-import "C"
+import "syscall"
 
-var _ C.complexfloat
-var _ C.complexdouble
+var syscall_dot_SIGCHLD syscall.Signal
diff --git a/libgo/misc/cgo/test/issue3250w.go b/libgo/misc/cgo/test/testdata/cgo_linux_test.go
index c2193aa1f1c..5cef09fbe77 100644
--- a/libgo/misc/cgo/test/issue3250w.go
+++ b/libgo/misc/cgo/test/testdata/cgo_linux_test.go
@@ -1,11 +1,9 @@
-// Copyright 2013 The Go Authors. All rights reserved.
+// Copyright 2012 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build windows
-
 package cgotest
 
 import "testing"
 
-func test3250(t *testing.T) {}
+func Test9400(t *testing.T) { test9400(t) }
diff --git a/libgo/misc/cgo/test/testdata/cgo_test.go b/libgo/misc/cgo/test/testdata/cgo_test.go
new file mode 100644
index 00000000000..ffa076f4eeb
--- /dev/null
+++ b/libgo/misc/cgo/test/testdata/cgo_test.go
@@ -0,0 +1,18 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cgotest
+
+import "testing"
+
+// The actual test functions are in non-_test.go files
+// so that they can use cgo (import "C").
+// These wrappers are here for gotest to find.
+
+func Test8756(t *testing.T)     { test8756(t) }
+func Test9026(t *testing.T)     { test9026(t) }
+func Test9510(t *testing.T)     { test9510(t) }
+func Test20266(t *testing.T)    { test20266(t) }
+func Test26213(t *testing.T)    { test26213(t) }
+func TestGCC68255(t *testing.T) { testGCC68255(t) }
diff --git a/libgo/misc/cgo/test/gcc68255.go b/libgo/misc/cgo/test/testdata/gcc68255.go
index 23e103dc109..b431462349c 100644
--- a/libgo/misc/cgo/test/gcc68255.go
+++ b/libgo/misc/cgo/test/testdata/gcc68255.go
@@ -7,7 +7,7 @@ package cgotest
 import (
 	"testing"
 
-	"./gcc68255"
+	"cgotest/gcc68255"
 )
 
 func testGCC68255(t *testing.T) {
diff --git a/libgo/misc/cgo/test/gcc68255/a.go b/libgo/misc/cgo/test/testdata/gcc68255/a.go
index e106dee3ec0..e106dee3ec0 100644
--- a/libgo/misc/cgo/test/gcc68255/a.go
+++ b/libgo/misc/cgo/test/testdata/gcc68255/a.go
diff --git a/libgo/misc/cgo/test/gcc68255/c.c b/libgo/misc/cgo/test/testdata/gcc68255/c.c
index a4fe193825b..a4fe193825b 100644
--- a/libgo/misc/cgo/test/gcc68255/c.c
+++ b/libgo/misc/cgo/test/testdata/gcc68255/c.c
diff --git a/libgo/misc/cgo/test/gcc68255/c.h b/libgo/misc/cgo/test/testdata/gcc68255/c.h
index 05ecd8187c7..05ecd8187c7 100644
--- a/libgo/misc/cgo/test/gcc68255/c.h
+++ b/libgo/misc/cgo/test/testdata/gcc68255/c.h
diff --git a/libgo/misc/cgo/test/issue20266.go b/libgo/misc/cgo/test/testdata/issue20266.go
index 9f95086cc7b..9f95086cc7b 100644
--- a/libgo/misc/cgo/test/issue20266.go
+++ b/libgo/misc/cgo/test/testdata/issue20266.go
diff --git a/libgo/misc/cgo/test/issue20266/issue20266.h b/libgo/misc/cgo/test/testdata/issue20266/issue20266.h
index 8d3258ec6b8..8d3258ec6b8 100644
--- a/libgo/misc/cgo/test/issue20266/issue20266.h
+++ b/libgo/misc/cgo/test/testdata/issue20266/issue20266.h
diff --git a/libgo/misc/cgo/test/issue23555.go b/libgo/misc/cgo/test/testdata/issue23555.go
index 5fa44e6355d..4e944b5acd4 100644
--- a/libgo/misc/cgo/test/issue23555.go
+++ b/libgo/misc/cgo/test/testdata/issue23555.go
@@ -7,5 +7,5 @@
 
 package cgotest
 
-import _ "./issue23555a"
-import _ "./issue23555b"
+import _ "cgotest/issue23555a"
+import _ "cgotest/issue23555b"
diff --git a/libgo/misc/cgo/test/issue23555a/a.go b/libgo/misc/cgo/test/testdata/issue23555a/a.go
index cb6626bb2b0..cb6626bb2b0 100644
--- a/libgo/misc/cgo/test/issue23555a/a.go
+++ b/libgo/misc/cgo/test/testdata/issue23555a/a.go
diff --git a/libgo/misc/cgo/test/issue23555b/a.go b/libgo/misc/cgo/test/testdata/issue23555b/a.go
index cb6626bb2b0..cb6626bb2b0 100644
--- a/libgo/misc/cgo/test/issue23555b/a.go
+++ b/libgo/misc/cgo/test/testdata/issue23555b/a.go
diff --git a/libgo/misc/cgo/test/issue24161_darwin_test.go b/libgo/misc/cgo/test/testdata/issue24161_darwin_test.go
index 48072ff121d..64f44428569 100644
--- a/libgo/misc/cgo/test/issue24161_darwin_test.go
+++ b/libgo/misc/cgo/test/testdata/issue24161_darwin_test.go
@@ -15,11 +15,11 @@ package cgotest
 import (
 	"testing"
 
-	"./issue24161arg"
-	"./issue24161e0"
-	"./issue24161e1"
-	"./issue24161e2"
-	"./issue24161res"
+	"cgotest/issue24161arg"
+	"cgotest/issue24161e0"
+	"cgotest/issue24161e1"
+	"cgotest/issue24161e2"
+	"cgotest/issue24161res"
 )
 
 func Test24161Arg(t *testing.T) {
diff --git a/libgo/misc/cgo/test/issue24161arg/def.go b/libgo/misc/cgo/test/testdata/issue24161arg/def.go
index d33479a891d..d33479a891d 100644
--- a/libgo/misc/cgo/test/issue24161arg/def.go
+++ b/libgo/misc/cgo/test/testdata/issue24161arg/def.go
diff --git a/libgo/misc/cgo/test/issue24161arg/use.go b/libgo/misc/cgo/test/testdata/issue24161arg/use.go
index 3e749440131..3e749440131 100644
--- a/libgo/misc/cgo/test/issue24161arg/use.go
+++ b/libgo/misc/cgo/test/testdata/issue24161arg/use.go
diff --git a/libgo/misc/cgo/test/issue24161e0/main.go b/libgo/misc/cgo/test/testdata/issue24161e0/main.go
index cbc1deea78a..cbc1deea78a 100644
--- a/libgo/misc/cgo/test/issue24161e0/main.go
+++ b/libgo/misc/cgo/test/testdata/issue24161e0/main.go
diff --git a/libgo/misc/cgo/test/issue24161e1/main.go b/libgo/misc/cgo/test/testdata/issue24161e1/main.go
index eb48fc0059d..eb48fc0059d 100644
--- a/libgo/misc/cgo/test/issue24161e1/main.go
+++ b/libgo/misc/cgo/test/testdata/issue24161e1/main.go
diff --git a/libgo/misc/cgo/test/issue24161e2/main.go b/libgo/misc/cgo/test/testdata/issue24161e2/main.go
index 1951c863175..1951c863175 100644
--- a/libgo/misc/cgo/test/issue24161e2/main.go
+++ b/libgo/misc/cgo/test/testdata/issue24161e2/main.go
diff --git a/libgo/misc/cgo/test/issue24161res/restype.go b/libgo/misc/cgo/test/testdata/issue24161res/restype.go
index e5719f22a40..e5719f22a40 100644
--- a/libgo/misc/cgo/test/issue24161res/restype.go
+++ b/libgo/misc/cgo/test/testdata/issue24161res/restype.go
diff --git a/libgo/misc/cgo/test/issue26213/jni.h b/libgo/misc/cgo/test/testdata/issue26213/jni.h
index 0c76979a5a0..0c76979a5a0 100644
--- a/libgo/misc/cgo/test/issue26213/jni.h
+++ b/libgo/misc/cgo/test/testdata/issue26213/jni.h
diff --git a/libgo/misc/cgo/test/issue26213/test26213.go b/libgo/misc/cgo/test/testdata/issue26213/test26213.go
index 5d1f637ff96..5d1f637ff96 100644
--- a/libgo/misc/cgo/test/issue26213/test26213.go
+++ b/libgo/misc/cgo/test/testdata/issue26213/test26213.go
diff --git a/libgo/misc/cgo/test/issue26430.go b/libgo/misc/cgo/test/testdata/issue26430.go
index 3ad54209896..14c7a7c3077 100644
--- a/libgo/misc/cgo/test/issue26430.go
+++ b/libgo/misc/cgo/test/testdata/issue26430.go
@@ -7,4 +7,4 @@
 
 package cgotest
 
-import _ "./issue26430"
+import _ "cgotest/issue26430"
diff --git a/libgo/misc/cgo/test/issue26430/a.go b/libgo/misc/cgo/test/testdata/issue26430/a.go
index fbaa46b1e8d..fbaa46b1e8d 100644
--- a/libgo/misc/cgo/test/issue26430/a.go
+++ b/libgo/misc/cgo/test/testdata/issue26430/a.go
diff --git a/libgo/misc/cgo/test/issue26430/b.go b/libgo/misc/cgo/test/testdata/issue26430/b.go
index a7c527cde3e..a7c527cde3e 100644
--- a/libgo/misc/cgo/test/issue26430/b.go
+++ b/libgo/misc/cgo/test/testdata/issue26430/b.go
diff --git a/libgo/misc/cgo/test/issue26743.go b/libgo/misc/cgo/test/testdata/issue26743.go
index 35c8473a61d..000fb2bfdf0 100644
--- a/libgo/misc/cgo/test/issue26743.go
+++ b/libgo/misc/cgo/test/testdata/issue26743.go
@@ -7,4 +7,4 @@
 
 package cgotest
 
-import _ "./issue26743"
+import _ "cgotest/issue26743"
diff --git a/libgo/misc/cgo/test/issue26743/a.go b/libgo/misc/cgo/test/testdata/issue26743/a.go
index a3df1797b3b..a3df1797b3b 100644
--- a/libgo/misc/cgo/test/issue26743/a.go
+++ b/libgo/misc/cgo/test/testdata/issue26743/a.go
diff --git a/libgo/misc/cgo/test/issue26743/b.go b/libgo/misc/cgo/test/testdata/issue26743/b.go
index c5f1ae478ca..c5f1ae478ca 100644
--- a/libgo/misc/cgo/test/issue26743/b.go
+++ b/libgo/misc/cgo/test/testdata/issue26743/b.go
diff --git a/libgo/misc/cgo/test/issue27054/egl.h b/libgo/misc/cgo/test/testdata/issue27054/egl.h
index 33a759ea2a8..33a759ea2a8 100644
--- a/libgo/misc/cgo/test/issue27054/egl.h
+++ b/libgo/misc/cgo/test/testdata/issue27054/egl.h
diff --git a/libgo/misc/cgo/test/issue27054/test27054.go b/libgo/misc/cgo/test/testdata/issue27054/test27054.go
index 186f5bd6020..186f5bd6020 100644
--- a/libgo/misc/cgo/test/issue27054/test27054.go
+++ b/libgo/misc/cgo/test/testdata/issue27054/test27054.go
diff --git a/libgo/misc/cgo/test/issue27340.go b/libgo/misc/cgo/test/testdata/issue27340.go
index f8c8a87f201..337550f6089 100644
--- a/libgo/misc/cgo/test/issue27340.go
+++ b/libgo/misc/cgo/test/testdata/issue27340.go
@@ -7,6 +7,6 @@
 
 package cgotest
 
-import "./issue27340"
+import "cgotest/issue27340"
 
 var issue27340Var = issue27340.Issue27340GoFunc
diff --git a/libgo/misc/cgo/test/issue27340/a.go b/libgo/misc/cgo/test/testdata/issue27340/a.go
index f5b120c1fd8..f5b120c1fd8 100644
--- a/libgo/misc/cgo/test/issue27340/a.go
+++ b/libgo/misc/cgo/test/testdata/issue27340/a.go
diff --git a/libgo/misc/cgo/test/issue21668.go b/libgo/misc/cgo/test/testdata/issue29563.go
index f15b9202acc..84def3ca444 100644
--- a/libgo/misc/cgo/test/issue21668.go
+++ b/libgo/misc/cgo/test/testdata/issue29563.go
@@ -1,13 +1,12 @@
-// Copyright 2017 The Go Authors. All rights reserved.
+// Copyright 2019 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Fail to guess the kind of the constant "x".
+// +build !windows
+
+// Issue 29563: internal linker fails on duplicate weak symbols.
 // No runtime test; just make sure it compiles.
 
 package cgotest
 
-// const int x = 42;
-import "C"
-
-var issue21668_X = C.x
+import _ "cgotest/issue29563"
diff --git a/libgo/misc/cgo/test/testdata/issue29563/weak.go b/libgo/misc/cgo/test/testdata/issue29563/weak.go
new file mode 100644
index 00000000000..21cf635ccae
--- /dev/null
+++ b/libgo/misc/cgo/test/testdata/issue29563/weak.go
@@ -0,0 +1,13 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package issue29563
+
+//int foo1();
+//int foo2();
+import "C"
+
+func Bar() int {
+	return int(C.foo1()) + int(C.foo2())
+}
diff --git a/libgo/misc/cgo/test/testdata/issue29563/weak1.c b/libgo/misc/cgo/test/testdata/issue29563/weak1.c
new file mode 100644
index 00000000000..86a22734adc
--- /dev/null
+++ b/libgo/misc/cgo/test/testdata/issue29563/weak1.c
@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+extern int weaksym __attribute__((__weak__));
+int weaksym = 42;
+
+int foo1()
+{
+	return weaksym;
+}
diff --git a/libgo/misc/cgo/test/testdata/issue29563/weak2.c b/libgo/misc/cgo/test/testdata/issue29563/weak2.c
new file mode 100644
index 00000000000..e01eae8b58f
--- /dev/null
+++ b/libgo/misc/cgo/test/testdata/issue29563/weak2.c
@@ -0,0 +1,11 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+extern int weaksym __attribute__((__weak__));
+int weaksym = 42;
+
+int foo2()
+{
+	return weaksym;
+}
diff --git a/libgo/misc/cgo/test/issue8756.go b/libgo/misc/cgo/test/testdata/issue8756.go
index d8ee3b8213d..406c64c0f39 100644
--- a/libgo/misc/cgo/test/issue8756.go
+++ b/libgo/misc/cgo/test/testdata/issue8756.go
@@ -8,7 +8,7 @@ import "C"
 import (
 	"testing"
 
-	"./issue8756"
+	"cgotest/issue8756"
 )
 
 func test8756(t *testing.T) {
diff --git a/libgo/misc/cgo/test/issue8756/issue8756.go b/libgo/misc/cgo/test/testdata/issue8756/issue8756.go
index 5f6b7778ff6..5f6b7778ff6 100644
--- a/libgo/misc/cgo/test/issue8756/issue8756.go
+++ b/libgo/misc/cgo/test/testdata/issue8756/issue8756.go
diff --git a/libgo/misc/cgo/test/issue8828.go b/libgo/misc/cgo/test/testdata/issue8828.go
index 304797c929c..0bca0f25cf8 100644
--- a/libgo/misc/cgo/test/issue8828.go
+++ b/libgo/misc/cgo/test/testdata/issue8828.go
@@ -9,7 +9,7 @@
 
 package cgotest
 
-import "./issue8828"
+import "cgotest/issue8828"
 
 func p() {
 	issue8828.Bar()
diff --git a/libgo/misc/cgo/test/issue8828/issue8828.c b/libgo/misc/cgo/test/testdata/issue8828/issue8828.c
index 27ec23a2605..27ec23a2605 100644
--- a/libgo/misc/cgo/test/issue8828/issue8828.c
+++ b/libgo/misc/cgo/test/testdata/issue8828/issue8828.c
diff --git a/libgo/misc/cgo/test/issue8828/trivial.go b/libgo/misc/cgo/test/testdata/issue8828/trivial.go
index e7b9a4e573d..e7b9a4e573d 100644
--- a/libgo/misc/cgo/test/issue8828/trivial.go
+++ b/libgo/misc/cgo/test/testdata/issue8828/trivial.go
diff --git a/libgo/misc/cgo/test/issue9026.go b/libgo/misc/cgo/test/testdata/issue9026.go
index 8848d0e8118..3f488816550 100644
--- a/libgo/misc/cgo/test/issue9026.go
+++ b/libgo/misc/cgo/test/testdata/issue9026.go
@@ -3,7 +3,7 @@ package cgotest
 import (
 	"testing"
 
-	"./issue9026"
+	"cgotest/issue9026"
 )
 
 func test9026(t *testing.T) { issue9026.Test(t) }
diff --git a/libgo/misc/cgo/test/issue9026/issue9026.go b/libgo/misc/cgo/test/testdata/issue9026/issue9026.go
index 149c26562ad..149c26562ad 100644
--- a/libgo/misc/cgo/test/issue9026/issue9026.go
+++ b/libgo/misc/cgo/test/testdata/issue9026/issue9026.go
diff --git a/libgo/misc/cgo/test/issue9400/asm_386.s b/libgo/misc/cgo/test/testdata/issue9400/asm_386.s
index 7f158b5c39d..7f158b5c39d 100644
--- a/libgo/misc/cgo/test/issue9400/asm_386.s
+++ b/libgo/misc/cgo/test/testdata/issue9400/asm_386.s
diff --git a/libgo/misc/cgo/test/issue9400/asm_amd64x.s b/libgo/misc/cgo/test/testdata/issue9400/asm_amd64x.s
index 48b86190a59..48b86190a59 100644
--- a/libgo/misc/cgo/test/issue9400/asm_amd64x.s
+++ b/libgo/misc/cgo/test/testdata/issue9400/asm_amd64x.s
diff --git a/libgo/misc/cgo/test/issue9400/asm_arm.s b/libgo/misc/cgo/test/testdata/issue9400/asm_arm.s
index 96c278520f3..96c278520f3 100644
--- a/libgo/misc/cgo/test/issue9400/asm_arm.s
+++ b/libgo/misc/cgo/test/testdata/issue9400/asm_arm.s
diff --git a/libgo/misc/cgo/test/issue9400/asm_arm64.s b/libgo/misc/cgo/test/testdata/issue9400/asm_arm64.s
index 2ebbfcca3b6..2ebbfcca3b6 100644
--- a/libgo/misc/cgo/test/issue9400/asm_arm64.s
+++ b/libgo/misc/cgo/test/testdata/issue9400/asm_arm64.s
diff --git a/libgo/misc/cgo/test/issue9400/asm_mips64x.s b/libgo/misc/cgo/test/testdata/issue9400/asm_mips64x.s
index 63dc90605e6..63dc90605e6 100644
--- a/libgo/misc/cgo/test/issue9400/asm_mips64x.s
+++ b/libgo/misc/cgo/test/testdata/issue9400/asm_mips64x.s
diff --git a/libgo/misc/cgo/test/issue9400/asm_mipsx.s b/libgo/misc/cgo/test/testdata/issue9400/asm_mipsx.s
index 7a927351942..7a927351942 100644
--- a/libgo/misc/cgo/test/issue9400/asm_mipsx.s
+++ b/libgo/misc/cgo/test/testdata/issue9400/asm_mipsx.s
diff --git a/libgo/misc/cgo/test/issue9400/asm_ppc64x.s b/libgo/misc/cgo/test/testdata/issue9400/asm_ppc64x.s
index c88ec3b21e7..c88ec3b21e7 100644
--- a/libgo/misc/cgo/test/issue9400/asm_ppc64x.s
+++ b/libgo/misc/cgo/test/testdata/issue9400/asm_ppc64x.s
diff --git a/libgo/misc/cgo/test/issue9400/asm_s390x.s b/libgo/misc/cgo/test/testdata/issue9400/asm_s390x.s
index fc9ad724c15..fc9ad724c15 100644
--- a/libgo/misc/cgo/test/issue9400/asm_s390x.s
+++ b/libgo/misc/cgo/test/testdata/issue9400/asm_s390x.s
diff --git a/libgo/misc/cgo/test/issue9400/gccgo.go b/libgo/misc/cgo/test/testdata/issue9400/gccgo.go
index a9b62b07a04..a9b62b07a04 100644
--- a/libgo/misc/cgo/test/issue9400/gccgo.go
+++ b/libgo/misc/cgo/test/testdata/issue9400/gccgo.go
diff --git a/libgo/misc/cgo/test/issue9400/stubs.go b/libgo/misc/cgo/test/testdata/issue9400/stubs.go
index e431c5a28a0..e431c5a28a0 100644
--- a/libgo/misc/cgo/test/issue9400/stubs.go
+++ b/libgo/misc/cgo/test/testdata/issue9400/stubs.go
diff --git a/libgo/misc/cgo/test/issue9400_linux.go b/libgo/misc/cgo/test/testdata/issue9400_linux.go
index 7719535d251..e94a9bb45f5 100644
--- a/libgo/misc/cgo/test/issue9400_linux.go
+++ b/libgo/misc/cgo/test/testdata/issue9400_linux.go
@@ -18,7 +18,7 @@ import (
 	"sync/atomic"
 	"testing"
 
-	"./issue9400"
+	"cgotest/issue9400"
 )
 
 func test9400(t *testing.T) {
diff --git a/libgo/misc/cgo/test/issue9510.go b/libgo/misc/cgo/test/testdata/issue9510.go
index efd3f770b6a..2c79fab97f3 100644
--- a/libgo/misc/cgo/test/issue9510.go
+++ b/libgo/misc/cgo/test/testdata/issue9510.go
@@ -11,8 +11,8 @@ import (
 	"runtime"
 	"testing"
 
-	"./issue9510a"
-	"./issue9510b"
+	"cgotest/issue9510a"
+	"cgotest/issue9510b"
 )
 
 func test9510(t *testing.T) {
diff --git a/libgo/misc/cgo/test/issue9510a/a.go b/libgo/misc/cgo/test/testdata/issue9510a/a.go
index 1a5224b8c68..1a5224b8c68 100644
--- a/libgo/misc/cgo/test/issue9510a/a.go
+++ b/libgo/misc/cgo/test/testdata/issue9510a/a.go
diff --git a/libgo/misc/cgo/test/issue9510b/b.go b/libgo/misc/cgo/test/testdata/issue9510b/b.go
index 5016b39597e..5016b39597e 100644
--- a/libgo/misc/cgo/test/issue9510b/b.go
+++ b/libgo/misc/cgo/test/testdata/issue9510b/b.go
diff --git a/libgo/misc/cgo/test/test26213.go b/libgo/misc/cgo/test/testdata/test26213.go
index 176a7ece9c1..c80032cb3b9 100644
--- a/libgo/misc/cgo/test/test26213.go
+++ b/libgo/misc/cgo/test/testdata/test26213.go
@@ -7,7 +7,7 @@ package cgotest
 import (
 	"testing"
 
-	"./issue26213"
+	"cgotest/issue26213"
 )
 
 func test26213(t *testing.T) {
diff --git a/libgo/misc/cgo/test/testx.go b/libgo/misc/cgo/test/testx.go
new file mode 100644
index 00000000000..67def903aba
--- /dev/null
+++ b/libgo/misc/cgo/test/testx.go
@@ -0,0 +1,519 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Test cases for cgo.
+// Both the import "C" prologue and the main file are sorted by issue number.
+// This file contains //export directives on Go functions
+// and so it must NOT contain C definitions (only declarations).
+// See test.go for C definitions.
+
+package cgotest
+
+import (
+	"runtime"
+	"runtime/debug"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"testing"
+	"time"
+	"unsafe"
+)
+
+/*
+// threads
+extern void doAdd(int, int);
+
+// issue 1328
+extern void BackIntoGo(void);
+void IntoC(void);
+
+// issue 1560
+// mysleep returns the absolute start time in ms.
+long long mysleep(int seconds);
+
+// twoSleep returns the absolute start time of the first sleep
+// in ms.
+long long twoSleep(int);
+
+// issue 3775
+void lockOSThreadCallback(void);
+inline static void lockOSThreadC(void)
+{
+        lockOSThreadCallback();
+}
+int usleep(unsigned usec);
+
+// issue 4054 part 2 - part 1 in test.go
+typedef enum {
+	A = 0,
+	B,
+	C,
+	D,
+	E,
+	F,
+	G,
+	H,
+	II,
+	J,
+} issue4054b;
+
+// issue 5548
+
+extern int issue5548_in_c(void);
+
+// issue 6833
+
+extern unsigned long long issue6833Func(unsigned int, unsigned long long);
+
+// issue 6907
+
+extern int CheckIssue6907C(_GoString_);
+
+// issue 7665
+
+extern void f7665(void);
+
+// issue 7978
+// Stack tracing didn't work during cgo code after calling a Go
+// callback.  Make sure GC works and the stack trace is correct.
+
+#include <stdint.h>
+
+void issue7978cb(void);
+
+// use ugly atomic variable sync since that doesn't require calling back into
+// Go code or OS dependencies
+static void issue7978c(uint32_t *sync) {
+	while(__atomic_load_n(sync, __ATOMIC_SEQ_CST) != 0)
+		;
+	__atomic_add_fetch(sync, 1, __ATOMIC_SEQ_CST);
+	while(__atomic_load_n(sync, __ATOMIC_SEQ_CST) != 2)
+		;
+	issue7978cb();
+	__atomic_add_fetch(sync, 1, __ATOMIC_SEQ_CST);
+	while(__atomic_load_n(sync, __ATOMIC_SEQ_CST) != 6)
+		;
+}
+
+// issue 8331 part 2 - part 1 in test.go
+// A typedef of an unnamed struct is the same struct when
+// #include'd twice.  No runtime test; just make sure it compiles.
+#include "issue8331.h"
+
+// issue 20910
+void callMulti(void);
+
+// issue 28772 part 2 - part 1 in issuex.go
+#define issue28772Constant2 2
+
+*/
+import "C"
+
+// exports
+
+//export ReturnIntLong
+func ReturnIntLong() (int, C.long) {
+	return 1, 2
+}
+
+//export gc
+func gc() {
+	runtime.GC()
+}
+
+// threads
+
+var sum struct {
+	sync.Mutex
+	i int
+}
+
+//export Add
+func Add(x int) {
+	defer func() {
+		recover()
+	}()
+	sum.Lock()
+	sum.i += x
+	sum.Unlock()
+	var p *int
+	*p = 2
+}
+
+func testCthread(t *testing.T) {
+	if runtime.GOOS == "darwin" && (runtime.GOARCH == "arm" || runtime.GOARCH == "arm64") {
+		t.Skip("the iOS exec wrapper is unable to properly handle the panic from Add")
+	}
+	sum.i = 0
+	C.doAdd(10, 6)
+
+	want := 10 * (10 - 1) / 2 * 6
+	if sum.i != want {
+		t.Fatalf("sum=%d, want %d", sum.i, want)
+	}
+}
+
+// issue 1328
+
+//export BackIntoGo
+func BackIntoGo() {
+	x := 1
+
+	for i := 0; i < 10000; i++ {
+		xvariadic(x)
+		if x != 1 {
+			panic("x is not 1?")
+		}
+	}
+}
+
+func xvariadic(x ...interface{}) {
+}
+
+func test1328(t *testing.T) {
+	C.IntoC()
+}
+
+// issue 1560
+
+var sleepDone = make(chan int64)
+
+// parallelSleep returns the absolute difference between the start time
+// of the two sleeps.
+func parallelSleep(n int) int64 {
+	t := int64(C.twoSleep(C.int(n))) - <-sleepDone
+	if t < 0 {
+		return -t
+	}
+	return t
+}
+
+//export BackgroundSleep
+func BackgroundSleep(n int32) {
+	go func() {
+		sleepDone <- int64(C.mysleep(C.int(n)))
+	}()
+}
+
+func testParallelSleep(t *testing.T) {
+	sleepSec := 1
+	dt := time.Duration(parallelSleep(sleepSec)) * time.Millisecond
+	t.Logf("difference in start time for two sleep(%d) is %v", sleepSec, dt)
+	// bug used to run sleeps in serial, producing a 2*sleepSec-second delay.
+	// we detect if the start times of those sleeps are > 0.5*sleepSec-second.
+	if dt >= time.Duration(sleepSec)*time.Second/2 {
+		t.Fatalf("parallel %d-second sleeps slept for %f seconds", sleepSec, dt.Seconds())
+	}
+}
+
+// issue 2462
+
+//export exportbyte
+func exportbyte() byte {
+	return 0
+}
+
+//export exportbool
+func exportbool() bool {
+	return false
+}
+
+//export exportrune
+func exportrune() rune {
+	return 0
+}
+
+//export exporterror
+func exporterror() error {
+	return nil
+}
+
+//export exportint
+func exportint() int {
+	return 0
+}
+
+//export exportuint
+func exportuint() uint {
+	return 0
+}
+
+//export exportuintptr
+func exportuintptr() uintptr {
+	return (uintptr)(0)
+}
+
+//export exportint8
+func exportint8() int8 {
+	return 0
+}
+
+//export exportuint8
+func exportuint8() uint8 {
+	return 0
+}
+
+//export exportint16
+func exportint16() int16 {
+	return 0
+}
+
+//export exportuint16
+func exportuint16() uint16 {
+	return 0
+}
+
+//export exportint32
+func exportint32() int32 {
+	return 0
+}
+
+//export exportuint32
+func exportuint32() uint32 {
+	return 0
+}
+
+//export exportint64
+func exportint64() int64 {
+	return 0
+}
+
+//export exportuint64
+func exportuint64() uint64 {
+	return 0
+}
+
+//export exportfloat32
+func exportfloat32() float32 {
+	return 0
+}
+
+//export exportfloat64
+func exportfloat64() float64 {
+	return 0
+}
+
+//export exportcomplex64
+func exportcomplex64() complex64 {
+	return 0
+}
+
+//export exportcomplex128
+func exportcomplex128() complex128 {
+	return 0
+}
+
+// issue 3741
+
+//export exportSliceIn
+func exportSliceIn(s []byte) bool {
+	return len(s) == cap(s)
+}
+
+//export exportSliceOut
+func exportSliceOut() []byte {
+	return []byte{1}
+}
+
+//export exportSliceInOut
+func exportSliceInOut(s []byte) []byte {
+	return s
+}
+
+// issue 3775
+
+func init() {
+	if runtime.GOOS == "android" {
+		return
+	}
+	// Same as test3775 but run during init so that
+	// there are two levels of internal runtime lock
+	// (1 for init, 1 for cgo).
+	// This would have been broken by CL 11663043.
+	C.lockOSThreadC()
+}
+
+func test3775(t *testing.T) {
+	if runtime.GOOS == "android" {
+		return
+	}
+	// Used to panic because of the UnlockOSThread below.
+	C.lockOSThreadC()
+}
+
+//export lockOSThreadCallback
+func lockOSThreadCallback() {
+	runtime.LockOSThread()
+	runtime.UnlockOSThread()
+	go C.usleep(10000)
+	runtime.Gosched()
+}
+
+// issue 4054 part 2 - part 1 in test.go
+
+var issue4054b = []int{C.A, C.B, C.C, C.D, C.E, C.F, C.G, C.H, C.II, C.J}
+
+//export issue5548FromC
+func issue5548FromC(s string, i int) int {
+	if len(s) == 4 && s == "test" && i == 42 {
+		return 12345
+	}
+	println("got", len(s), i)
+	return 9876
+}
+
+func test5548(t *testing.T) {
+	if x := C.issue5548_in_c(); x != 12345 {
+		t.Errorf("issue5548_in_c = %d, want %d", x, 12345)
+	}
+}
+
+// issue 6833
+
+//export GoIssue6833Func
+func GoIssue6833Func(aui uint, aui64 uint64) uint64 {
+	return aui64 + uint64(aui)
+}
+
+func test6833(t *testing.T) {
+	ui := 7
+	ull := uint64(0x4000300020001000)
+	v := uint64(C.issue6833Func(C.uint(ui), C.ulonglong(ull)))
+	exp := uint64(ui) + ull
+	if v != exp {
+		t.Errorf("issue6833Func() returns %x, expected %x", v, exp)
+	}
+}
+
+// issue 6907
+
+const CString = "C string"
+
+//export CheckIssue6907Go
+func CheckIssue6907Go(s string) C.int {
+	if s == CString {
+		return 1
+	}
+	return 0
+}
+
+func test6907Go(t *testing.T) {
+	if got := C.CheckIssue6907C(CString); got != 1 {
+		t.Errorf("C.CheckIssue6907C() == %d, want %d", got, 1)
+	}
+}
+
+// issue 7665
+
+//export f7665
+func f7665() {}
+
+var bad7665 unsafe.Pointer = C.f7665
+var good7665 uintptr = uintptr(C.f7665)
+
+func test7665(t *testing.T) {
+	if bad7665 == nil || uintptr(bad7665) != good7665 {
+		t.Errorf("ptrs = %p, %#x, want same non-nil pointer", bad7665, good7665)
+	}
+}
+
+// issue 7978
+
+var issue7978sync uint32
+
+func issue7978check(t *testing.T, wantFunc string, badFunc string, depth int) {
+	runtime.GC()
+	buf := make([]byte, 65536)
+	trace := string(buf[:runtime.Stack(buf, true)])
+	for _, goroutine := range strings.Split(trace, "\n\n") {
+		if strings.Contains(goroutine, "test.issue7978go") {
+			trace := strings.Split(goroutine, "\n")
+			// look for the expected function in the stack
+			for i := 0; i < depth; i++ {
+				if badFunc != "" && strings.Contains(trace[1+2*i], badFunc) {
+					t.Errorf("bad stack: found %s in the stack:\n%s", badFunc, goroutine)
+					return
+				}
+				if strings.Contains(trace[1+2*i], wantFunc) {
+					return
+				}
+			}
+			t.Errorf("bad stack: didn't find %s in the stack:\n%s", wantFunc, goroutine)
+			return
+		}
+	}
+	t.Errorf("bad stack: goroutine not found. Full stack dump:\n%s", trace)
+}
+
+func issue7978wait(store uint32, wait uint32) {
+	if store != 0 {
+		atomic.StoreUint32(&issue7978sync, store)
+	}
+	for atomic.LoadUint32(&issue7978sync) != wait {
+		runtime.Gosched()
+	}
+}
+
+//export issue7978cb
+func issue7978cb() {
+	// Force a stack growth from the callback to put extra
+	// pressure on the runtime. See issue #17785.
+	growStack(64)
+	issue7978wait(3, 4)
+}
+
+func growStack(n int) int {
+	var buf [128]int
+	if n == 0 {
+		return 0
+	}
+	return buf[growStack(n-1)]
+}
+
+func issue7978go() {
+	C.issue7978c((*C.uint32_t)(&issue7978sync))
+	issue7978wait(7, 8)
+}
+
+func test7978(t *testing.T) {
+	if runtime.Compiler == "gccgo" {
+		t.Skip("gccgo can not do stack traces of C code")
+	}
+	debug.SetTraceback("2")
+	issue7978sync = 0
+	go issue7978go()
+	// test in c code, before callback
+	issue7978wait(0, 1)
+	issue7978check(t, "_Cfunc_issue7978c(", "", 1)
+	// test in go code, during callback
+	issue7978wait(2, 3)
+	issue7978check(t, "test.issue7978cb(", "test.issue7978go", 3)
+	// test in c code, after callback
+	issue7978wait(4, 5)
+	issue7978check(t, "_Cfunc_issue7978c(", "_cgoexpwrap", 1)
+	// test in go code, after return from cgo
+	issue7978wait(6, 7)
+	issue7978check(t, "test.issue7978go(", "", 3)
+	atomic.StoreUint32(&issue7978sync, 8)
+}
+
+// issue 8331 part 2
+
+var issue8331Var C.issue8331
+
+// issue 20910
+
+//export multi
+func multi() (*C.char, C.int) {
+	return C.CString("multi"), 0
+}
+
+func test20910(t *testing.T) {
+	C.callMulti()
+}
+
+// issue 28772 part 2
+
+const issue28772Constant2 = C.issue28772Constant2
diff --git a/libgo/misc/cgo/test/twoargs.go b/libgo/misc/cgo/test/twoargs.go
deleted file mode 100644
index ca0534ca310..00000000000
--- a/libgo/misc/cgo/test/twoargs.go
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Crash from call with two arguments that need pointer checking.
-// No runtime test; just make sure it compiles.
-
-package cgotest
-
-/*
-static void twoargs1(void *p, int n) {}
-static void *twoargs2() { return 0; }
-static int twoargs3(void * p) { return 0; }
-*/
-import "C"
-
-import "unsafe"
-
-func twoargsF() {
-	v := []string{}
-	C.twoargs1(C.twoargs2(), C.twoargs3(unsafe.Pointer(&v)))
-}
diff --git a/libgo/misc/cgo/testcarchive/carchive_test.go b/libgo/misc/cgo/testcarchive/carchive_test.go
index 457ac0db091..70516703d96 100644
--- a/libgo/misc/cgo/testcarchive/carchive_test.go
+++ b/libgo/misc/cgo/testcarchive/carchive_test.go
@@ -8,8 +8,10 @@ import (
 	"bufio"
 	"bytes"
 	"debug/elf"
+	"flag"
 	"fmt"
 	"io/ioutil"
+	"log"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -28,16 +30,47 @@ var bin []string
 // C compiler with args (from $(go env CC) $(go env GOGCCFLAGS)).
 var cc []string
 
-// An environment with GOPATH=$(pwd).
-var gopathEnv []string
-
 // ".exe" on Windows.
 var exeSuffix string
 
-var GOOS, GOARCH string
+var GOOS, GOARCH, GOPATH string
 var libgodir string
 
-func init() {
+func TestMain(m *testing.M) {
+	flag.Parse()
+	if testing.Short() && os.Getenv("GO_BUILDER_NAME") == "" {
+		fmt.Printf("SKIP - short mode and $GO_BUILDER_NAME not set\n")
+		os.Exit(0)
+	}
+	log.SetFlags(log.Lshortfile)
+	os.Exit(testMain(m))
+}
+
+func testMain(m *testing.M) int {
+	// We need a writable GOPATH in which to run the tests.
+	// Construct one in a temporary directory.
+	var err error
+	GOPATH, err = ioutil.TempDir("", "carchive_test")
+	if err != nil {
+		log.Panic(err)
+	}
+	defer os.RemoveAll(GOPATH)
+	os.Setenv("GOPATH", GOPATH)
+
+	// Copy testdata into GOPATH/src/testarchive, along with a go.mod file
+	// declaring the same path.
+	modRoot := filepath.Join(GOPATH, "src", "testcarchive")
+	if err := overlayDir(modRoot, "testdata"); err != nil {
+		log.Panic(err)
+	}
+	if err := os.Chdir(modRoot); err != nil {
+		log.Panic(err)
+	}
+	os.Setenv("PWD", modRoot)
+	if err := ioutil.WriteFile("go.mod", []byte("module testcarchive\n"), 0666); err != nil {
+		log.Panic(err)
+	}
+
 	GOOS = goEnv("GOOS")
 	GOARCH = goEnv("GOARCH")
 	bin = cmdToRun("./testp")
@@ -83,50 +116,41 @@ func init() {
 		// TODO(crawshaw): can we do better?
 		cc = append(cc, []string{"-framework", "CoreFoundation", "-framework", "Foundation"}...)
 	}
-	libgodir = GOOS + "_" + GOARCH
+	if GOOS == "aix" {
+		// -Wl,-bnoobjreorder is mandatory to keep the same layout
+		// in .text section.
+		cc = append(cc, "-Wl,-bnoobjreorder")
+	}
+	libbase := GOOS + "_" + GOARCH
 	if runtime.Compiler == "gccgo" {
-		libgodir = "gccgo_" + libgodir + "_fPIC"
+		libbase = "gccgo_" + libbase + "_fPIC"
 	} else {
 		switch GOOS {
 		case "darwin":
 			if GOARCH == "arm" || GOARCH == "arm64" {
-				libgodir += "_shared"
+				libbase += "_shared"
 			}
-		case "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "solaris":
-			libgodir += "_shared"
+		case "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "solaris", "illumos":
+			libbase += "_shared"
 		}
 	}
-	cc = append(cc, "-I", filepath.Join("pkg", libgodir))
-
-	// Build an environment with GOPATH=$(pwd)
-	env := os.Environ()
-	var n []string
-	for _, e := range env {
-		if !strings.HasPrefix(e, "GOPATH=") {
-			n = append(n, e)
-		}
-	}
-	dir, err := os.Getwd()
-	if err != nil {
-		fmt.Fprintln(os.Stderr, err)
-		os.Exit(2)
-	}
-	n = append(n, "GOPATH="+dir)
-	gopathEnv = n
+	libgodir = filepath.Join(GOPATH, "pkg", libbase, "testcarchive")
+	cc = append(cc, "-I", libgodir)
 
 	if GOOS == "windows" {
 		exeSuffix = ".exe"
 	}
+
+	return m.Run()
 }
 
 func goEnv(key string) string {
 	out, err := exec.Command("go", "env", key).Output()
 	if err != nil {
-		fmt.Fprintf(os.Stderr, "go env %s failed:\n%s\n", key, err)
 		if ee, ok := err.(*exec.ExitError); ok {
 			fmt.Fprintf(os.Stderr, "%s", ee.Stderr)
 		}
-		os.Exit(2)
+		log.Panicf("go env %s failed:\n%s\n", key, err)
 	}
 	return strings.TrimSpace(string(out))
 }
@@ -143,7 +167,6 @@ func cmdToRun(name string) []string {
 func testInstall(t *testing.T, exe, libgoa, libgoh string, buildcmd ...string) {
 	t.Helper()
 	cmd := exec.Command(buildcmd[0], buildcmd[1:]...)
-	cmd.Env = gopathEnv
 	t.Log(buildcmd)
 	if out, err := cmd.CombinedOutput(); err != nil {
 		t.Logf("%s", out)
@@ -204,7 +227,7 @@ func checkLineComments(t *testing.T, hdrname string) {
 }
 
 func TestInstall(t *testing.T) {
-	defer os.RemoveAll("pkg")
+	defer os.RemoveAll(filepath.Join(GOPATH, "pkg"))
 
 	libgoa := "libgo.a"
 	if runtime.Compiler == "gccgo" {
@@ -212,17 +235,17 @@ func TestInstall(t *testing.T) {
 	}
 
 	testInstall(t, "./testp1"+exeSuffix,
-		filepath.Join("pkg", libgodir, libgoa),
-		filepath.Join("pkg", libgodir, "libgo.h"),
-		"go", "install", "-i", "-buildmode=c-archive", "libgo")
+		filepath.Join(libgodir, libgoa),
+		filepath.Join(libgodir, "libgo.h"),
+		"go", "install", "-i", "-buildmode=c-archive", "./libgo")
 
 	// Test building libgo other than installing it.
 	// Header files are now present.
 	testInstall(t, "./testp2"+exeSuffix, "libgo.a", "libgo.h",
-		"go", "build", "-buildmode=c-archive", filepath.Join("src", "libgo", "libgo.go"))
+		"go", "build", "-buildmode=c-archive", filepath.Join(".", "libgo", "libgo.go"))
 
 	testInstall(t, "./testp3"+exeSuffix, "libgo.a", "libgo.h",
-		"go", "build", "-buildmode=c-archive", "-o", "libgo.a", "libgo")
+		"go", "build", "-buildmode=c-archive", "-o", "libgo.a", "./libgo")
 }
 
 func TestEarlySignalHandler(t *testing.T) {
@@ -240,11 +263,10 @@ func TestEarlySignalHandler(t *testing.T) {
 		os.Remove("libgo2.a")
 		os.Remove("libgo2.h")
 		os.Remove("testp")
-		os.RemoveAll("pkg")
+		os.RemoveAll(filepath.Join(GOPATH, "pkg"))
 	}()
 
-	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo2.a", "libgo2")
-	cmd.Env = gopathEnv
+	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo2.a", "./libgo2")
 	if out, err := cmd.CombinedOutput(); err != nil {
 		t.Logf("%s", out)
 		t.Fatal(err)
@@ -273,11 +295,10 @@ func TestSignalForwarding(t *testing.T) {
 		os.Remove("libgo2.a")
 		os.Remove("libgo2.h")
 		os.Remove("testp")
-		os.RemoveAll("pkg")
+		os.RemoveAll(filepath.Join(GOPATH, "pkg"))
 	}()
 
-	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo2.a", "libgo2")
-	cmd.Env = gopathEnv
+	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo2.a", "./libgo2")
 	if out, err := cmd.CombinedOutput(); err != nil {
 		t.Logf("%s", out)
 		t.Fatal(err)
@@ -308,8 +329,10 @@ func TestSignalForwarding(t *testing.T) {
 }
 
 func TestSignalForwardingExternal(t *testing.T) {
-	if GOOS == "freebsd" {
+	if GOOS == "freebsd" || GOOS == "aix" {
 		t.Skipf("skipping on %s/%s; signal always goes to the Go runtime", GOOS, GOARCH)
+	} else if GOOS == "darwin" && GOARCH == "amd64" {
+		t.Skipf("skipping on %s/%s: runtime does not permit SI_USER SIGSEGV", GOOS, GOARCH)
 	}
 	checkSignalForwardingTest(t)
 
@@ -317,11 +340,10 @@ func TestSignalForwardingExternal(t *testing.T) {
 		os.Remove("libgo2.a")
 		os.Remove("libgo2.h")
 		os.Remove("testp")
-		os.RemoveAll("pkg")
+		os.RemoveAll(filepath.Join(GOPATH, "pkg"))
 	}()
 
-	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo2.a", "libgo2")
-	cmd.Env = gopathEnv
+	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo2.a", "./libgo2")
 	if out, err := cmd.CombinedOutput(); err != nil {
 		t.Logf("%s", out)
 		t.Fatal(err)
@@ -433,11 +455,10 @@ func TestOsSignal(t *testing.T) {
 		os.Remove("libgo3.a")
 		os.Remove("libgo3.h")
 		os.Remove("testp")
-		os.RemoveAll("pkg")
+		os.RemoveAll(filepath.Join(GOPATH, "pkg"))
 	}()
 
-	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo3.a", "libgo3")
-	cmd.Env = gopathEnv
+	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo3.a", "./libgo3")
 	if out, err := cmd.CombinedOutput(); err != nil {
 		t.Logf("%s", out)
 		t.Fatal(err)
@@ -469,11 +490,10 @@ func TestSigaltstack(t *testing.T) {
 		os.Remove("libgo4.a")
 		os.Remove("libgo4.h")
 		os.Remove("testp")
-		os.RemoveAll("pkg")
+		os.RemoveAll(filepath.Join(GOPATH, "pkg"))
 	}()
 
-	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo4.a", "libgo4")
-	cmd.Env = gopathEnv
+	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo4.a", "./libgo4")
 	if out, err := cmd.CombinedOutput(); err != nil {
 		t.Logf("%s", out)
 		t.Fatal(err)
@@ -511,13 +531,16 @@ func TestExtar(t *testing.T) {
 	if runtime.Compiler == "gccgo" {
 		t.Skip("skipping -extar test when using gccgo")
 	}
+	if runtime.GOOS == "darwin" && (runtime.GOARCH == "arm" || runtime.GOARCH == "arm64") {
+		t.Skip("shell scripts are not executable on iOS hosts")
+	}
 
 	defer func() {
 		os.Remove("libgo4.a")
 		os.Remove("libgo4.h")
 		os.Remove("testar")
 		os.Remove("testar.ran")
-		os.RemoveAll("pkg")
+		os.RemoveAll(filepath.Join(GOPATH, "pkg"))
 	}()
 
 	os.Remove("testar")
@@ -530,8 +553,7 @@ func TestExtar(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-ldflags=-extar="+filepath.Join(dir, "testar"), "-o", "libgo4.a", "libgo4")
-	cmd.Env = gopathEnv
+	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-ldflags=-extar="+filepath.Join(dir, "testar"), "-o", "libgo4.a", "./libgo4")
 	if out, err := cmd.CombinedOutput(); err != nil {
 		t.Logf("%s", out)
 		t.Fatal(err)
@@ -555,11 +577,10 @@ func TestPIE(t *testing.T) {
 
 	defer func() {
 		os.Remove("testp" + exeSuffix)
-		os.RemoveAll("pkg")
+		os.RemoveAll(filepath.Join(GOPATH, "pkg"))
 	}()
 
-	cmd := exec.Command("go", "install", "-i", "-buildmode=c-archive", "libgo")
-	cmd.Env = gopathEnv
+	cmd := exec.Command("go", "install", "-i", "-buildmode=c-archive", "./libgo")
 	if out, err := cmd.CombinedOutput(); err != nil {
 		t.Logf("%s", out)
 		t.Fatal(err)
@@ -570,7 +591,7 @@ func TestPIE(t *testing.T) {
 		libgoa = "liblibgo.a"
 	}
 
-	ccArgs := append(cc, "-fPIE", "-pie", "-o", "testp"+exeSuffix, "main.c", "main_unix.c", filepath.Join("pkg", libgodir, libgoa))
+	ccArgs := append(cc, "-fPIE", "-pie", "-o", "testp"+exeSuffix, "main.c", "main_unix.c", filepath.Join(libgodir, libgoa))
 	if runtime.Compiler == "gccgo" {
 		ccArgs = append(ccArgs, "-lgo")
 	}
@@ -589,13 +610,15 @@ func TestPIE(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	f, err := elf.Open("testp" + exeSuffix)
-	if err != nil {
-		t.Fatal("elf.Open failed: ", err)
-	}
-	defer f.Close()
-	if hasDynTag(t, f, elf.DT_TEXTREL) {
-		t.Errorf("%s has DT_TEXTREL flag", "testp"+exeSuffix)
+	if GOOS != "aix" {
+		f, err := elf.Open("testp" + exeSuffix)
+		if err != nil {
+			t.Fatal("elf.Open failed: ", err)
+		}
+		defer f.Close()
+		if hasDynTag(t, f, elf.DT_TEXTREL) {
+			t.Errorf("%s has DT_TEXTREL flag", "testp"+exeSuffix)
+		}
 	}
 }
 
@@ -643,8 +666,7 @@ func TestSIGPROF(t *testing.T) {
 		os.Remove("libgo6.h")
 	}()
 
-	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo6.a", "libgo6")
-	cmd.Env = gopathEnv
+	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-o", "libgo6.a", "./libgo6")
 	if out, err := cmd.CombinedOutput(); err != nil {
 		t.Logf("%s", out)
 		t.Fatal(err)
@@ -683,8 +705,7 @@ func TestCompileWithoutShared(t *testing.T) {
 		os.Remove("libgo2.h")
 	}()
 
-	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-gcflags=-shared=false", "-o", "libgo2.a", "libgo2")
-	cmd.Env = gopathEnv
+	cmd := exec.Command("go", "build", "-buildmode=c-archive", "-gcflags=-shared=false", "-o", "libgo2.a", "./libgo2")
 	t.Log(cmd.Args)
 	out, err := cmd.CombinedOutput()
 	t.Logf("%s", out)
@@ -732,15 +753,14 @@ func TestCompileWithoutShared(t *testing.T) {
 
 // Test that installing a second time recreates the header files.
 func TestCachedInstall(t *testing.T) {
-	defer os.RemoveAll("pkg")
+	defer os.RemoveAll(filepath.Join(GOPATH, "pkg"))
 
-	h1 := filepath.Join("pkg", libgodir, "libgo.h")
-	h2 := filepath.Join("pkg", libgodir, "p.h")
+	h1 := filepath.Join(libgodir, "libgo.h")
+	h2 := filepath.Join(libgodir, "p.h")
 
-	buildcmd := []string{"go", "install", "-i", "-buildmode=c-archive", "libgo"}
+	buildcmd := []string{"go", "install", "-i", "-buildmode=c-archive", "./libgo"}
 
 	cmd := exec.Command(buildcmd[0], buildcmd[1:]...)
-	cmd.Env = gopathEnv
 	t.Log(buildcmd)
 	if out, err := cmd.CombinedOutput(); err != nil {
 		t.Logf("%s", out)
@@ -762,7 +782,6 @@ func TestCachedInstall(t *testing.T) {
 	}
 
 	cmd = exec.Command(buildcmd[0], buildcmd[1:]...)
-	cmd.Env = gopathEnv
 	t.Log(buildcmd)
 	if out, err := cmd.CombinedOutput(); err != nil {
 		t.Logf("%s", out)
diff --git a/libgo/misc/cgo/testcarchive/overlaydir_test.go b/libgo/misc/cgo/testcarchive/overlaydir_test.go
new file mode 100644
index 00000000000..68878e4c66a
--- /dev/null
+++ b/libgo/misc/cgo/testcarchive/overlaydir_test.go
@@ -0,0 +1,81 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package carchive_test
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// overlayDir makes a minimal-overhead copy of srcRoot in which new files may be added.
+//
+// TODO: Once we no longer need to support the misc module in GOPATH mode,
+// factor this function out into a package to reduce duplication.
+func overlayDir(dstRoot, srcRoot string) error {
+	dstRoot = filepath.Clean(dstRoot)
+	if err := os.MkdirAll(dstRoot, 0777); err != nil {
+		return err
+	}
+
+	symBase, err := filepath.Rel(srcRoot, dstRoot)
+	if err != nil {
+		symBase, err = filepath.Abs(srcRoot)
+		if err != nil {
+			return err
+		}
+	}
+
+	return filepath.Walk(srcRoot, func(srcPath string, info os.FileInfo, err error) error {
+		if err != nil || srcPath == srcRoot {
+			return err
+		}
+
+		suffix := strings.TrimPrefix(srcPath, srcRoot)
+		for len(suffix) > 0 && suffix[0] == filepath.Separator {
+			suffix = suffix[1:]
+		}
+		dstPath := filepath.Join(dstRoot, suffix)
+
+		perm := info.Mode() & os.ModePerm
+		if info.Mode()&os.ModeSymlink != 0 {
+			info, err = os.Stat(srcPath)
+			if err != nil {
+				return err
+			}
+			perm = info.Mode() & os.ModePerm
+		}
+
+		// Always copy directories (don't symlink them).
+		// If we add a file in the overlay, we don't want to add it in the original.
+		if info.IsDir() {
+			return os.Mkdir(dstPath, perm)
+		}
+
+		// If the OS supports symlinks, use them instead of copying bytes.
+		if err := os.Symlink(filepath.Join(symBase, suffix), dstPath); err == nil {
+			return nil
+		}
+
+		// Otherwise, copy the bytes.
+		src, err := os.Open(srcPath)
+		if err != nil {
+			return err
+		}
+		defer src.Close()
+
+		dst, err := os.OpenFile(dstPath, os.O_WRONLY|os.O_CREATE|os.O_EXCL, perm)
+		if err != nil {
+			return err
+		}
+
+		_, err = io.Copy(dst, src)
+		if closeErr := dst.Close(); err == nil {
+			err = closeErr
+		}
+		return err
+	})
+}
diff --git a/libgo/misc/cgo/testcarchive/src/libgo/libgo.go b/libgo/misc/cgo/testcarchive/testdata/libgo/libgo.go
index 45958a546cb..37b30c14632 100644
--- a/libgo/misc/cgo/testcarchive/src/libgo/libgo.go
+++ b/libgo/misc/cgo/testcarchive/testdata/libgo/libgo.go
@@ -10,7 +10,7 @@ import (
 	"syscall"
 	"time"
 
-	_ "p"
+	_ "testcarchive/p"
 )
 
 import "C"
diff --git a/libgo/misc/cgo/testcarchive/src/libgo2/libgo2.go b/libgo/misc/cgo/testcarchive/testdata/libgo2/libgo2.go
index 19c8e1a6dcb..19c8e1a6dcb 100644
--- a/libgo/misc/cgo/testcarchive/src/libgo2/libgo2.go
+++ b/libgo/misc/cgo/testcarchive/testdata/libgo2/libgo2.go
diff --git a/libgo/misc/cgo/testcarchive/src/libgo3/libgo3.go b/libgo/misc/cgo/testcarchive/testdata/libgo3/libgo3.go
index 3725f7ab0ff..3725f7ab0ff 100644
--- a/libgo/misc/cgo/testcarchive/src/libgo3/libgo3.go
+++ b/libgo/misc/cgo/testcarchive/testdata/libgo3/libgo3.go
diff --git a/libgo/misc/cgo/testcarchive/src/libgo4/libgo4.go b/libgo/misc/cgo/testcarchive/testdata/libgo4/libgo4.go
index 8cc1895f99f..8cc1895f99f 100644
--- a/libgo/misc/cgo/testcarchive/src/libgo4/libgo4.go
+++ b/libgo/misc/cgo/testcarchive/testdata/libgo4/libgo4.go
diff --git a/libgo/misc/cgo/testcarchive/src/libgo6/sigprof.go b/libgo/misc/cgo/testcarchive/testdata/libgo6/sigprof.go
index 4cb05dc6178..4cb05dc6178 100644
--- a/libgo/misc/cgo/testcarchive/src/libgo6/sigprof.go
+++ b/libgo/misc/cgo/testcarchive/testdata/libgo6/sigprof.go
diff --git a/libgo/misc/cgo/testcarchive/main.c b/libgo/misc/cgo/testcarchive/testdata/main.c
index 163b5398e5e..163b5398e5e 100644
--- a/libgo/misc/cgo/testcarchive/main.c
+++ b/libgo/misc/cgo/testcarchive/testdata/main.c
diff --git a/libgo/misc/cgo/testcarchive/main2.c b/libgo/misc/cgo/testcarchive/testdata/main2.c
index 769cd497e6c..769cd497e6c 100644
--- a/libgo/misc/cgo/testcarchive/main2.c
+++ b/libgo/misc/cgo/testcarchive/testdata/main2.c
diff --git a/libgo/misc/cgo/testcarchive/main3.c b/libgo/misc/cgo/testcarchive/testdata/main3.c
index 60a16cf5fc4..60a16cf5fc4 100644
--- a/libgo/misc/cgo/testcarchive/main3.c
+++ b/libgo/misc/cgo/testcarchive/testdata/main3.c
diff --git a/libgo/misc/cgo/testcarchive/main4.c b/libgo/misc/cgo/testcarchive/testdata/main4.c
index 4fd55e753d5..04f774008f1 100644
--- a/libgo/misc/cgo/testcarchive/main4.c
+++ b/libgo/misc/cgo/testcarchive/testdata/main4.c
@@ -14,6 +14,13 @@
 
 #include "libgo4.h"
 
+#ifdef _AIX
+// On AIX, CSIGSTKSZ is too small to handle Go sighandler.
+#define CSIGSTKSZ 0x4000
+#else
+#define CSIGSTKSZ SIGSTKSZ
+#endif
+
 static void die(const char* msg) {
 	perror(msg);
 	exit(EXIT_FAILURE);
@@ -53,12 +60,12 @@ static void* thread1(void* arg __attribute__ ((unused))) {
 
 	// Set up an alternate signal stack for this thread.
 	memset(&ss, 0, sizeof ss);
-	ss.ss_sp = malloc(SIGSTKSZ);
+	ss.ss_sp = malloc(CSIGSTKSZ);
 	if (ss.ss_sp == NULL) {
 		die("malloc");
 	}
 	ss.ss_flags = 0;
-	ss.ss_size = SIGSTKSZ;
+	ss.ss_size = CSIGSTKSZ;
 	if (sigaltstack(&ss, NULL) < 0) {
 		die("sigaltstack");
 	}
@@ -93,7 +100,7 @@ static void* thread1(void* arg __attribute__ ((unused))) {
 		fprintf(stderr, "sigaltstack disabled on return from Go\n");
 		ok = 0;
 	} else if (nss.ss_sp != ss.ss_sp) {
-		fprintf(stderr, "sigalstack changed on return from Go\n");
+		fprintf(stderr, "sigaltstack changed on return from Go\n");
 		ok = 0;
 	}
 
@@ -112,12 +119,12 @@ static void* thread2(void* arg __attribute__ ((unused))) {
 
 	// Set up an alternate signal stack for this thread.
 	memset(&ss, 0, sizeof ss);
-	ss.ss_sp = malloc(SIGSTKSZ);
+	ss.ss_sp = malloc(CSIGSTKSZ);
 	if (ss.ss_sp == NULL) {
 		die("malloc");
 	}
 	ss.ss_flags = 0;
-	ss.ss_size = SIGSTKSZ;
+	ss.ss_size = CSIGSTKSZ;
 	if (sigaltstack(&ss, NULL) < 0) {
 		die("sigaltstack");
 	}
@@ -150,7 +157,7 @@ static void* thread2(void* arg __attribute__ ((unused))) {
 		fprintf(stderr, "sigaltstack disabled on return from Go\n");
 		ok = 0;
 	} else if (nss.ss_sp != ss.ss_sp) {
-		fprintf(stderr, "sigalstack changed on return from Go\n");
+		fprintf(stderr, "sigaltstack changed on return from Go\n");
 		ok = 0;
 	}
 
diff --git a/libgo/misc/cgo/testcarchive/main5.c b/libgo/misc/cgo/testcarchive/testdata/main5.c
index 897b70d2fa6..d431ce01ce5 100644
--- a/libgo/misc/cgo/testcarchive/main5.c
+++ b/libgo/misc/cgo/testcarchive/testdata/main5.c
@@ -14,6 +14,8 @@
 
 #include "libgo2.h"
 
+int *nilp;
+
 int main(int argc, char** argv) {
 	int verbose;
 	int test;
@@ -39,7 +41,7 @@ int main(int argc, char** argv) {
 				printf("attempting segfault\n");
 			}
 
-			volatile int crash = *(int *) 0;
+			*nilp = 0;
 			break;
 		}
 
@@ -85,7 +87,7 @@ int main(int argc, char** argv) {
 				printf("write(2) unexpectedly succeeded\n");
 				return 0;
 			}
-			printf("did not receieve SIGPIPE\n");
+			printf("did not receive SIGPIPE\n");
 			return 0;
 		}
 		default:
diff --git a/libgo/misc/cgo/testcarchive/main6.c b/libgo/misc/cgo/testcarchive/testdata/main6.c
index 2745eb9dc5e..2745eb9dc5e 100644
--- a/libgo/misc/cgo/testcarchive/main6.c
+++ b/libgo/misc/cgo/testcarchive/testdata/main6.c
diff --git a/libgo/misc/cgo/testcarchive/main_unix.c b/libgo/misc/cgo/testcarchive/testdata/main_unix.c
index b23ac1c2428..b23ac1c2428 100644
--- a/libgo/misc/cgo/testcarchive/main_unix.c
+++ b/libgo/misc/cgo/testcarchive/testdata/main_unix.c
diff --git a/libgo/misc/cgo/testcarchive/main_windows.c b/libgo/misc/cgo/testcarchive/testdata/main_windows.c
index eded8af1a2c..eded8af1a2c 100644
--- a/libgo/misc/cgo/testcarchive/main_windows.c
+++ b/libgo/misc/cgo/testcarchive/testdata/main_windows.c
diff --git a/libgo/misc/cgo/testcarchive/src/p/p.go b/libgo/misc/cgo/testcarchive/testdata/p/p.go
index 82b445c1210..82b445c1210 100644
--- a/libgo/misc/cgo/testcarchive/src/p/p.go
+++ b/libgo/misc/cgo/testcarchive/testdata/p/p.go
diff --git a/libgo/misc/cgo/testcshared/cshared_test.go b/libgo/misc/cgo/testcshared/cshared_test.go
index e5b90ff194c..daef3a9e546 100644
--- a/libgo/misc/cgo/testcshared/cshared_test.go
+++ b/libgo/misc/cgo/testcshared/cshared_test.go
@@ -5,14 +5,16 @@
 package cshared_test
 
 import (
+	"bytes"
 	"debug/elf"
+	"flag"
 	"fmt"
 	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
-	"path"
 	"path/filepath"
+	"runtime"
 	"strings"
 	"sync"
 	"testing"
@@ -22,9 +24,6 @@ import (
 // C compiler with args (from $(go env CC) $(go env GOGCCFLAGS)).
 var cc []string
 
-// An environment with GOPATH=$(pwd).
-var gopathEnv []string
-
 // ".exe" on Windows.
 var exeSuffix string
 
@@ -33,6 +32,17 @@ var installdir, androiddir string
 var libSuffix, libgoname string
 
 func TestMain(m *testing.M) {
+	os.Exit(testMain(m))
+}
+
+func testMain(m *testing.M) int {
+	log.SetFlags(log.Lshortfile)
+	flag.Parse()
+	if testing.Short() && os.Getenv("GO_BUILDER_NAME") == "" {
+		fmt.Printf("SKIP - short mode and $GO_BUILDER_NAME not set\n")
+		os.Exit(0)
+	}
+
 	GOOS = goEnv("GOOS")
 	GOARCH = goEnv("GOARCH")
 	GOROOT = goEnv("GOROOT")
@@ -41,31 +51,17 @@ func TestMain(m *testing.M) {
 		log.Fatalf("Unable able to find GOROOT at '%s'", GOROOT)
 	}
 
-	// Directory where cgo headers and outputs will be installed.
-	// The installation directory format varies depending on the platform.
-	installdir = path.Join("pkg", fmt.Sprintf("%s_%s_testcshared", GOOS, GOARCH))
-	switch GOOS {
-	case "darwin":
-		libSuffix = "dylib"
-	case "windows":
-		libSuffix = "dll"
-	default:
-		libSuffix = "so"
-		installdir = path.Join("pkg", fmt.Sprintf("%s_%s_testcshared_shared", GOOS, GOARCH))
-	}
-
 	androiddir = fmt.Sprintf("/data/local/tmp/testcshared-%d", os.Getpid())
-	if GOOS == "android" {
-		args := append(adbCmd(), "shell", "mkdir", "-p", androiddir)
+	if runtime.GOOS != GOOS && GOOS == "android" {
+		args := append(adbCmd(), "exec-out", "mkdir", "-p", androiddir)
 		cmd := exec.Command(args[0], args[1:]...)
 		out, err := cmd.CombinedOutput()
 		if err != nil {
 			log.Fatalf("setupAndroid failed: %v\n%s\n", err, out)
 		}
+		defer cleanupAndroid()
 	}
 
-	libgoname = "libgo." + libSuffix
-
 	cc = []string{goEnv("CC")}
 
 	out := goEnv("GOGCCFLAGS")
@@ -115,39 +111,62 @@ func TestMain(m *testing.M) {
 		if GOARCH == "arm" || GOARCH == "arm64" {
 			libgodir += "_shared"
 		}
-	case "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "solaris":
+	case "dragonfly", "freebsd", "linux", "netbsd", "openbsd", "solaris", "illumos":
 		libgodir += "_shared"
 	}
 	cc = append(cc, "-I", filepath.Join("pkg", libgodir))
 
-	// Build an environment with GOPATH=$(pwd)
-	dir, err := os.Getwd()
-	if err != nil {
-		fmt.Fprintln(os.Stderr, err)
-		os.Exit(2)
-	}
-	gopathEnv = append(os.Environ(), "GOPATH="+dir)
-
 	if GOOS == "windows" {
 		exeSuffix = ".exe"
 	}
 
-	st := m.Run()
+	// Copy testdata into GOPATH/src/testcshared, along with a go.mod file
+	// declaring the same path.
 
-	os.Remove(libgoname)
-	os.RemoveAll("pkg")
-	cleanupHeaders()
-	cleanupAndroid()
+	GOPATH, err := ioutil.TempDir("", "cshared_test")
+	if err != nil {
+		log.Panic(err)
+	}
+	defer os.RemoveAll(GOPATH)
+	os.Setenv("GOPATH", GOPATH)
 
-	os.Exit(st)
+	// Copy testdata into GOPATH/src/testarchive, along with a go.mod file
+	// declaring the same path.
+	modRoot := filepath.Join(GOPATH, "src", "testcshared")
+	if err := overlayDir(modRoot, "testdata"); err != nil {
+		log.Panic(err)
+	}
+	if err := os.Chdir(modRoot); err != nil {
+		log.Panic(err)
+	}
+	os.Setenv("PWD", modRoot)
+	if err := ioutil.WriteFile("go.mod", []byte("module testcshared\n"), 0666); err != nil {
+		log.Panic(err)
+	}
+
+	// Directory where cgo headers and outputs will be installed.
+	// The installation directory format varies depending on the platform.
+	output, err := exec.Command("go", "list",
+		"-buildmode=c-shared",
+		"-installsuffix", "testcshared",
+		"-f", "{{.Target}}",
+		"./libgo").CombinedOutput()
+	if err != nil {
+		log.Panicf("go list failed: %v\n%s", err, output)
+	}
+	target := string(bytes.TrimSpace(output))
+	libgoname = filepath.Base(target)
+	installdir = filepath.Dir(target)
+	libSuffix = strings.TrimPrefix(filepath.Ext(target), ".")
+
+	return m.Run()
 }
 
 func goEnv(key string) string {
 	out, err := exec.Command("go", "env", key).Output()
 	if err != nil {
-		fmt.Fprintf(os.Stderr, "go env %s failed:\n%s", key, err)
-		fmt.Fprintf(os.Stderr, "%s", err.(*exec.ExitError).Stderr)
-		os.Exit(2)
+		log.Printf("go env %s failed:\n%s", key, err)
+		log.Panicf("%s", err.(*exec.ExitError).Stderr)
 	}
 	return strings.TrimSpace(string(out))
 }
@@ -165,7 +184,7 @@ func adbCmd() []string {
 }
 
 func adbPush(t *testing.T, filename string) {
-	if GOOS != "android" {
+	if runtime.GOOS == GOOS || GOOS != "android" {
 		return
 	}
 	args := append(adbCmd(), "push", filename, fmt.Sprintf("%s/%s", androiddir, filename))
@@ -179,7 +198,7 @@ func adbRun(t *testing.T, env []string, adbargs ...string) string {
 	if GOOS != "android" {
 		t.Fatalf("trying to run adb command when operating system is not android.")
 	}
-	args := append(adbCmd(), "shell")
+	args := append(adbCmd(), "exec-out")
 	// Propagate LD_LIBRARY_PATH to the adb shell invocation.
 	for _, e := range env {
 		if strings.Index(e, "LD_LIBRARY_PATH=") != -1 {
@@ -197,10 +216,12 @@ func adbRun(t *testing.T, env []string, adbargs ...string) string {
 	return strings.Replace(string(out), "\r", "", -1)
 }
 
-func run(t *testing.T, env []string, args ...string) string {
+func run(t *testing.T, extraEnv []string, args ...string) string {
 	t.Helper()
 	cmd := exec.Command(args[0], args[1:]...)
-	cmd.Env = env
+	if len(extraEnv) > 0 {
+		cmd.Env = append(os.Environ(), extraEnv...)
+	}
 
 	if GOOS != "windows" {
 		// TestUnexportedSymbols relies on file descriptor 30
@@ -220,12 +241,12 @@ func run(t *testing.T, env []string, args ...string) string {
 	return string(out)
 }
 
-func runExe(t *testing.T, env []string, args ...string) string {
+func runExe(t *testing.T, extraEnv []string, args ...string) string {
 	t.Helper()
-	if GOOS == "android" {
-		return adbRun(t, env, args...)
+	if runtime.GOOS != GOOS && GOOS == "android" {
+		return adbRun(t, append(os.Environ(), extraEnv...), args...)
 	}
-	return run(t, env, args...)
+	return run(t, extraEnv, args...)
 }
 
 func runCC(t *testing.T, args ...string) string {
@@ -237,9 +258,8 @@ func runCC(t *testing.T, args ...string) string {
 
 func createHeaders() error {
 	args := []string{"go", "install", "-i", "-buildmode=c-shared",
-		"-installsuffix", "testcshared", "libgo"}
+		"-installsuffix", "testcshared", "./libgo"}
 	cmd := exec.Command(args[0], args[1:]...)
-	cmd.Env = gopathEnv
 	out, err := cmd.CombinedOutput()
 	if err != nil {
 		return fmt.Errorf("command failed: %v\n%v\n%s\n", args, err, out)
@@ -248,15 +268,14 @@ func createHeaders() error {
 	args = []string{"go", "build", "-buildmode=c-shared",
 		"-installsuffix", "testcshared",
 		"-o", libgoname,
-		filepath.Join("src", "libgo", "libgo.go")}
+		filepath.Join(".", "libgo", "libgo.go")}
 	cmd = exec.Command(args[0], args[1:]...)
-	cmd.Env = gopathEnv
 	out, err = cmd.CombinedOutput()
 	if err != nil {
 		return fmt.Errorf("command failed: %v\n%v\n%s\n", args, err, out)
 	}
 
-	if GOOS == "android" {
+	if runtime.GOOS != GOOS && GOOS == "android" {
 		args = append(adbCmd(), "push", libgoname, fmt.Sprintf("%s/%s", androiddir, libgoname))
 		cmd = exec.Command(args[0], args[1:]...)
 		out, err = cmd.CombinedOutput()
@@ -282,19 +301,15 @@ func createHeadersOnce(t *testing.T) {
 	}
 }
 
-func cleanupHeaders() {
-	os.Remove("libgo.h")
-}
-
 func cleanupAndroid() {
 	if GOOS != "android" {
 		return
 	}
-	args := append(adbCmd(), "shell", "rm", "-rf", androiddir)
+	args := append(adbCmd(), "exec-out", "rm", "-rf", androiddir)
 	cmd := exec.Command(args[0], args[1:]...)
 	out, err := cmd.CombinedOutput()
 	if err != nil {
-		log.Fatalf("cleanupAndroid failed: %v\n%s\n", err, out)
+		log.Panicf("cleanupAndroid failed: %v\n%s\n", err, out)
 	}
 }
 
@@ -312,7 +327,7 @@ func TestExportedSymbols(t *testing.T) {
 
 	defer os.Remove(bin)
 
-	out := runExe(t, append(gopathEnv, "LD_LIBRARY_PATH=."), bin)
+	out := runExe(t, []string{"LD_LIBRARY_PATH=."}, bin)
 	if strings.TrimSpace(out) != "PASS" {
 		t.Error(out)
 	}
@@ -361,11 +376,11 @@ func TestUnexportedSymbols(t *testing.T) {
 	libname := "libgo2." + libSuffix
 
 	run(t,
-		gopathEnv,
+		nil,
 		"go", "build",
 		"-buildmode=c-shared",
 		"-installsuffix", "testcshared",
-		"-o", libname, "libgo2",
+		"-o", libname, "./libgo2",
 	)
 	adbPush(t, libname)
 
@@ -380,7 +395,7 @@ func TestUnexportedSymbols(t *testing.T) {
 	defer os.Remove(libname)
 	defer os.Remove(bin)
 
-	out := runExe(t, append(gopathEnv, "LD_LIBRARY_PATH=."), bin)
+	out := runExe(t, []string{"LD_LIBRARY_PATH=."}, bin)
 
 	if strings.TrimSpace(out) != "PASS" {
 		t.Error(out)
@@ -418,7 +433,7 @@ func TestMainExportedOnAndroid(t *testing.T) {
 func testSignalHandlers(t *testing.T, pkgname, cfile, cmd string) {
 	libname := pkgname + "." + libSuffix
 	run(t,
-		gopathEnv,
+		nil,
 		"go", "build",
 		"-buildmode=c-shared",
 		"-installsuffix", "testcshared",
@@ -451,7 +466,7 @@ func TestSignalHandlers(t *testing.T) {
 		t.Logf("Skipping on %s", GOOS)
 		return
 	}
-	testSignalHandlers(t, "libgo4", "main4.c", "testp4")
+	testSignalHandlers(t, "./libgo4", "main4.c", "testp4")
 }
 
 // test5: test signal handlers with os/signal.Notify
@@ -461,7 +476,7 @@ func TestSignalHandlersWithNotify(t *testing.T) {
 		t.Logf("Skipping on %s", GOOS)
 		return
 	}
-	testSignalHandlers(t, "libgo5", "main5.c", "testp5")
+	testSignalHandlers(t, "./libgo5", "main5.c", "testp5")
 }
 
 func TestPIE(t *testing.T) {
@@ -513,16 +528,18 @@ func TestCachedInstall(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	// defer os.RemoveAll(tmpdir)
+	defer os.RemoveAll(tmpdir)
 
-	copyFile(t, filepath.Join(tmpdir, "src", "libgo", "libgo.go"), filepath.Join("src", "libgo", "libgo.go"))
-	copyFile(t, filepath.Join(tmpdir, "src", "p", "p.go"), filepath.Join("src", "p", "p.go"))
+	copyFile(t, filepath.Join(tmpdir, "src", "testcshared", "go.mod"), "go.mod")
+	copyFile(t, filepath.Join(tmpdir, "src", "testcshared", "libgo", "libgo.go"), filepath.Join("libgo", "libgo.go"))
+	copyFile(t, filepath.Join(tmpdir, "src", "testcshared", "p", "p.go"), filepath.Join("p", "p.go"))
 
-	env := append(os.Environ(), "GOPATH="+tmpdir)
+	env := append(os.Environ(), "GOPATH="+tmpdir, "GOBIN="+filepath.Join(tmpdir, "bin"))
 
-	buildcmd := []string{"go", "install", "-x", "-i", "-buildmode=c-shared", "-installsuffix", "testcshared", "libgo"}
+	buildcmd := []string{"go", "install", "-x", "-i", "-buildmode=c-shared", "-installsuffix", "testcshared", "./libgo"}
 
 	cmd := exec.Command(buildcmd[0], buildcmd[1:]...)
+	cmd.Dir = filepath.Join(tmpdir, "src", "testcshared")
 	cmd.Env = env
 	t.Log(buildcmd)
 	out, err := cmd.CombinedOutput()
@@ -572,6 +589,7 @@ func TestCachedInstall(t *testing.T) {
 	}
 
 	cmd = exec.Command(buildcmd[0], buildcmd[1:]...)
+	cmd.Dir = filepath.Join(tmpdir, "src", "testcshared")
 	cmd.Env = env
 	t.Log(buildcmd)
 	out, err = cmd.CombinedOutput()
@@ -621,8 +639,8 @@ func TestGo2C2Go(t *testing.T) {
 	}
 	defer os.RemoveAll(tmpdir)
 
-	shlib := filepath.Join(tmpdir, "libtestgo2c2go."+libSuffix)
-	run(t, gopathEnv, "go", "build", "-buildmode=c-shared", "-o", shlib, "go2c2go/go")
+	lib := filepath.Join(tmpdir, "libtestgo2c2go."+libSuffix)
+	run(t, nil, "go", "build", "-buildmode=c-shared", "-o", lib, "./go2c2go/go")
 
 	cgoCflags := os.Getenv("CGO_CFLAGS")
 	if cgoCflags != "" {
@@ -636,7 +654,7 @@ func TestGo2C2Go(t *testing.T) {
 	}
 	cgoLdflags += "-L" + tmpdir + " -ltestgo2c2go"
 
-	goenv := append(gopathEnv[:len(gopathEnv):len(gopathEnv)], "CGO_CFLAGS="+cgoCflags, "CGO_LDFLAGS="+cgoLdflags)
+	goenv := []string{"CGO_CFLAGS=" + cgoCflags, "CGO_LDFLAGS=" + cgoLdflags}
 
 	ldLibPath := os.Getenv("LD_LIBRARY_PATH")
 	if ldLibPath != "" {
@@ -644,13 +662,13 @@ func TestGo2C2Go(t *testing.T) {
 	}
 	ldLibPath += tmpdir
 
-	runenv := append(gopathEnv[:len(gopathEnv):len(gopathEnv)], "LD_LIBRARY_PATH="+ldLibPath)
+	runenv := []string{"LD_LIBRARY_PATH=" + ldLibPath}
 
 	bin := filepath.Join(tmpdir, "m1") + exeSuffix
-	run(t, goenv, "go", "build", "-o", bin, "go2c2go/m1")
+	run(t, goenv, "go", "build", "-o", bin, "./go2c2go/m1")
 	runExe(t, runenv, bin)
 
 	bin = filepath.Join(tmpdir, "m2") + exeSuffix
-	run(t, goenv, "go", "build", "-o", bin, "go2c2go/m2")
+	run(t, goenv, "go", "build", "-o", bin, "./go2c2go/m2")
 	runExe(t, runenv, bin)
 }
diff --git a/libgo/misc/cgo/testcshared/overlaydir_test.go b/libgo/misc/cgo/testcshared/overlaydir_test.go
new file mode 100644
index 00000000000..1eaabf6fe21
--- /dev/null
+++ b/libgo/misc/cgo/testcshared/overlaydir_test.go
@@ -0,0 +1,81 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package cshared_test
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// overlayDir makes a minimal-overhead copy of srcRoot in which new files may be added.
+//
+// TODO: Once we no longer need to support the misc module in GOPATH mode,
+// factor this function out into a package to reduce duplication.
+func overlayDir(dstRoot, srcRoot string) error {
+	dstRoot = filepath.Clean(dstRoot)
+	if err := os.MkdirAll(dstRoot, 0777); err != nil {
+		return err
+	}
+
+	symBase, err := filepath.Rel(srcRoot, dstRoot)
+	if err != nil {
+		symBase, err = filepath.Abs(srcRoot)
+		if err != nil {
+			return err
+		}
+	}
+
+	return filepath.Walk(srcRoot, func(srcPath string, info os.FileInfo, err error) error {
+		if err != nil || srcPath == srcRoot {
+			return err
+		}
+
+		suffix := strings.TrimPrefix(srcPath, srcRoot)
+		for len(suffix) > 0 && suffix[0] == filepath.Separator {
+			suffix = suffix[1:]
+		}
+		dstPath := filepath.Join(dstRoot, suffix)
+
+		perm := info.Mode() & os.ModePerm
+		if info.Mode()&os.ModeSymlink != 0 {
+			info, err = os.Stat(srcPath)
+			if err != nil {
+				return err
+			}
+			perm = info.Mode() & os.ModePerm
+		}
+
+		// Always copy directories (don't symlink them).
+		// If we add a file in the overlay, we don't want to add it in the original.
+		if info.IsDir() {
+			return os.Mkdir(dstPath, perm)
+		}
+
+		// If the OS supports symlinks, use them instead of copying bytes.
+		if err := os.Symlink(filepath.Join(symBase, suffix), dstPath); err == nil {
+			return nil
+		}
+
+		// Otherwise, copy the bytes.
+		src, err := os.Open(srcPath)
+		if err != nil {
+			return err
+		}
+		defer src.Close()
+
+		dst, err := os.OpenFile(dstPath, os.O_WRONLY|os.O_CREATE|os.O_EXCL, perm)
+		if err != nil {
+			return err
+		}
+
+		_, err = io.Copy(dst, src)
+		if closeErr := dst.Close(); err == nil {
+			err = closeErr
+		}
+		return err
+	})
+}
diff --git a/libgo/misc/cgo/testcshared/src/go2c2go/go/shlib.go b/libgo/misc/cgo/testcshared/testdata/go2c2go/go/shlib.go
index 76a5323ad2d..76a5323ad2d 100644
--- a/libgo/misc/cgo/testcshared/src/go2c2go/go/shlib.go
+++ b/libgo/misc/cgo/testcshared/testdata/go2c2go/go/shlib.go
diff --git a/libgo/misc/cgo/testcshared/src/go2c2go/m1/c.c b/libgo/misc/cgo/testcshared/testdata/go2c2go/m1/c.c
index 0e8fac4cf36..0e8fac4cf36 100644
--- a/libgo/misc/cgo/testcshared/src/go2c2go/m1/c.c
+++ b/libgo/misc/cgo/testcshared/testdata/go2c2go/m1/c.c
diff --git a/libgo/misc/cgo/testcshared/src/go2c2go/m1/main.go b/libgo/misc/cgo/testcshared/testdata/go2c2go/m1/main.go
index 17ba1eb0a72..17ba1eb0a72 100644
--- a/libgo/misc/cgo/testcshared/src/go2c2go/m1/main.go
+++ b/libgo/misc/cgo/testcshared/testdata/go2c2go/m1/main.go
diff --git a/libgo/misc/cgo/testcshared/src/go2c2go/m2/main.go b/libgo/misc/cgo/testcshared/testdata/go2c2go/m2/main.go
index 91bf308057c..91bf308057c 100644
--- a/libgo/misc/cgo/testcshared/src/go2c2go/m2/main.go
+++ b/libgo/misc/cgo/testcshared/testdata/go2c2go/m2/main.go
diff --git a/libgo/misc/cgo/testcshared/src/libgo/libgo.go b/libgo/misc/cgo/testcshared/testdata/libgo/libgo.go
index 8a4bf795e91..063441766a1 100644
--- a/libgo/misc/cgo/testcshared/src/libgo/libgo.go
+++ b/libgo/misc/cgo/testcshared/testdata/libgo/libgo.go
@@ -5,8 +5,8 @@
 package main
 
 import (
-	_ "p"
 	"syscall"
+	_ "testcshared/p"
 	"time"
 )
 
diff --git a/libgo/misc/cgo/testcshared/src/libgo2/dup2.go b/libgo/misc/cgo/testcshared/testdata/libgo2/dup2.go
index d343aa54d9a..d18f0b130d3 100644
--- a/libgo/misc/cgo/testcshared/src/libgo2/dup2.go
+++ b/libgo/misc/cgo/testcshared/testdata/libgo2/dup2.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build darwin dragonfly freebsd linux,!arm64,!riscv64 netbsd openbsd
+// +build darwin dragonfly freebsd linux,!arm64 netbsd openbsd
 
 package main
 
diff --git a/libgo/misc/cgo/testcshared/src/libgo2/dup3.go b/libgo/misc/cgo/testcshared/testdata/libgo2/dup3.go
index 459f0dc1968..c9c65a6e3c1 100644
--- a/libgo/misc/cgo/testcshared/src/libgo2/dup3.go
+++ b/libgo/misc/cgo/testcshared/testdata/libgo2/dup3.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build linux,arm64 linux,riscv64
+// +build linux,arm64
 
 package main
 
diff --git a/libgo/misc/cgo/testcshared/src/libgo2/libgo2.go b/libgo/misc/cgo/testcshared/testdata/libgo2/libgo2.go
index e57c93b77d7..e57c93b77d7 100644
--- a/libgo/misc/cgo/testcshared/src/libgo2/libgo2.go
+++ b/libgo/misc/cgo/testcshared/testdata/libgo2/libgo2.go
diff --git a/libgo/misc/cgo/testcshared/src/libgo4/libgo4.go b/libgo/misc/cgo/testcshared/testdata/libgo4/libgo4.go
index ab40b75e78a..ab40b75e78a 100644
--- a/libgo/misc/cgo/testcshared/src/libgo4/libgo4.go
+++ b/libgo/misc/cgo/testcshared/testdata/libgo4/libgo4.go
diff --git a/libgo/misc/cgo/testcshared/src/libgo5/libgo5.go b/libgo/misc/cgo/testcshared/testdata/libgo5/libgo5.go
index 94e5d21c14a..94e5d21c14a 100644
--- a/libgo/misc/cgo/testcshared/src/libgo5/libgo5.go
+++ b/libgo/misc/cgo/testcshared/testdata/libgo5/libgo5.go
diff --git a/libgo/misc/cgo/testcshared/main0.c b/libgo/misc/cgo/testcshared/testdata/main0.c
index 39ef7e30513..39ef7e30513 100644
--- a/libgo/misc/cgo/testcshared/main0.c
+++ b/libgo/misc/cgo/testcshared/testdata/main0.c
diff --git a/libgo/misc/cgo/testcshared/main1.c b/libgo/misc/cgo/testcshared/testdata/main1.c
index 420dd1ea974..420dd1ea974 100644
--- a/libgo/misc/cgo/testcshared/main1.c
+++ b/libgo/misc/cgo/testcshared/testdata/main1.c
diff --git a/libgo/misc/cgo/testcshared/main2.c b/libgo/misc/cgo/testcshared/testdata/main2.c
index f89bcca474f..f89bcca474f 100644
--- a/libgo/misc/cgo/testcshared/main2.c
+++ b/libgo/misc/cgo/testcshared/testdata/main2.c
diff --git a/libgo/misc/cgo/testcshared/main3.c b/libgo/misc/cgo/testcshared/testdata/main3.c
index 49cc0558a01..49cc0558a01 100644
--- a/libgo/misc/cgo/testcshared/main3.c
+++ b/libgo/misc/cgo/testcshared/testdata/main3.c
diff --git a/libgo/misc/cgo/testcshared/main4.c b/libgo/misc/cgo/testcshared/testdata/main4.c
index 355cdefb017..355cdefb017 100644
--- a/libgo/misc/cgo/testcshared/main4.c
+++ b/libgo/misc/cgo/testcshared/testdata/main4.c
diff --git a/libgo/misc/cgo/testcshared/main5.c b/libgo/misc/cgo/testcshared/testdata/main5.c
index 1bc99101d7a..1bc99101d7a 100644
--- a/libgo/misc/cgo/testcshared/main5.c
+++ b/libgo/misc/cgo/testcshared/testdata/main5.c
diff --git a/libgo/misc/cgo/testcshared/src/p/p.go b/libgo/misc/cgo/testcshared/testdata/p/p.go
index 0f02cf3ce6c..0f02cf3ce6c 100644
--- a/libgo/misc/cgo/testcshared/src/p/p.go
+++ b/libgo/misc/cgo/testcshared/testdata/p/p.go
diff --git a/libgo/misc/cgo/testgodefs/test.bash b/libgo/misc/cgo/testgodefs/test.bash
index 012d007fc3e..e4ce2ee7a86 100644
--- a/libgo/misc/cgo/testgodefs/test.bash
+++ b/libgo/misc/cgo/testgodefs/test.bash
@@ -9,6 +9,8 @@
 # import "C" block.  Add more tests here.
 FILE_PREFIXES="anonunion issue8478 fieldtypedef"
 
+cd testdata
+
 RM=
 for FP in $FILE_PREFIXES
 do
@@ -16,7 +18,7 @@ do
   RM="${RM} ${FP}_defs.go"
 done
 
-go build . && ./testgodefs
+go build -o testgodefs . && ./testgodefs
 EXIT=$?
 rm -rf _obj testgodefs ${RM}
 exit $EXIT
diff --git a/libgo/misc/cgo/testgodefs/anonunion.go b/libgo/misc/cgo/testgodefs/testdata/anonunion.go
index 18840f2577c..18840f2577c 100644
--- a/libgo/misc/cgo/testgodefs/anonunion.go
+++ b/libgo/misc/cgo/testgodefs/testdata/anonunion.go
diff --git a/libgo/misc/cgo/testgodefs/fieldtypedef.go b/libgo/misc/cgo/testgodefs/testdata/fieldtypedef.go
index 45c0bf86530..45c0bf86530 100644
--- a/libgo/misc/cgo/testgodefs/fieldtypedef.go
+++ b/libgo/misc/cgo/testgodefs/testdata/fieldtypedef.go
diff --git a/libgo/misc/cgo/testgodefs/issue8478.go b/libgo/misc/cgo/testgodefs/testdata/issue8478.go
index 23214461711..23214461711 100644
--- a/libgo/misc/cgo/testgodefs/issue8478.go
+++ b/libgo/misc/cgo/testgodefs/testdata/issue8478.go
diff --git a/libgo/misc/cgo/testgodefs/main.go b/libgo/misc/cgo/testgodefs/testdata/main.go
index 1ce0fd0d1e1..1ce0fd0d1e1 100644
--- a/libgo/misc/cgo/testgodefs/main.go
+++ b/libgo/misc/cgo/testgodefs/testdata/main.go
diff --git a/libgo/misc/cgo/testplugin/altpath/src/common/common.go b/libgo/misc/cgo/testplugin/altpath/testdata/common/common.go
index 505ba02b1f1..505ba02b1f1 100644
--- a/libgo/misc/cgo/testplugin/altpath/src/common/common.go
+++ b/libgo/misc/cgo/testplugin/altpath/testdata/common/common.go
diff --git a/libgo/misc/cgo/testplugin/altpath/src/plugin-mismatch/main.go b/libgo/misc/cgo/testplugin/altpath/testdata/plugin-mismatch/main.go
index 8aacafc4530..bfb4ba45aa2 100644
--- a/libgo/misc/cgo/testplugin/altpath/src/plugin-mismatch/main.go
+++ b/libgo/misc/cgo/testplugin/altpath/testdata/plugin-mismatch/main.go
@@ -10,7 +10,7 @@ import "C"
 // The common package imported here does not match the common package
 // imported by plugin1. A program that attempts to load plugin1 and
 // plugin-mismatch should produce an error.
-import "common"
+import "testplugin/common"
 
 func ReadCommonX() int {
 	return common.X
diff --git a/libgo/misc/cgo/testplugin/overlaydir_test.go b/libgo/misc/cgo/testplugin/overlaydir_test.go
new file mode 100644
index 00000000000..b68436ac035
--- /dev/null
+++ b/libgo/misc/cgo/testplugin/overlaydir_test.go
@@ -0,0 +1,81 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package plugin_test
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// overlayDir makes a minimal-overhead copy of srcRoot in which new files may be added.
+//
+// TODO: Once we no longer need to support the misc module in GOPATH mode,
+// factor this function out into a package to reduce duplication.
+func overlayDir(dstRoot, srcRoot string) error {
+	dstRoot = filepath.Clean(dstRoot)
+	if err := os.MkdirAll(dstRoot, 0777); err != nil {
+		return err
+	}
+
+	symBase, err := filepath.Rel(srcRoot, dstRoot)
+	if err != nil {
+		symBase, err = filepath.Abs(srcRoot)
+		if err != nil {
+			return err
+		}
+	}
+
+	return filepath.Walk(srcRoot, func(srcPath string, info os.FileInfo, err error) error {
+		if err != nil || srcPath == srcRoot {
+			return err
+		}
+
+		suffix := strings.TrimPrefix(srcPath, srcRoot)
+		for len(suffix) > 0 && suffix[0] == filepath.Separator {
+			suffix = suffix[1:]
+		}
+		dstPath := filepath.Join(dstRoot, suffix)
+
+		perm := info.Mode() & os.ModePerm
+		if info.Mode()&os.ModeSymlink != 0 {
+			info, err = os.Stat(srcPath)
+			if err != nil {
+				return err
+			}
+			perm = info.Mode() & os.ModePerm
+		}
+
+		// Always copy directories (don't symlink them).
+		// If we add a file in the overlay, we don't want to add it in the original.
+		if info.IsDir() {
+			return os.Mkdir(dstPath, perm)
+		}
+
+		// If the OS supports symlinks, use them instead of copying bytes.
+		if err := os.Symlink(filepath.Join(symBase, suffix), dstPath); err == nil {
+			return nil
+		}
+
+		// Otherwise, copy the bytes.
+		src, err := os.Open(srcPath)
+		if err != nil {
+			return err
+		}
+		defer src.Close()
+
+		dst, err := os.OpenFile(dstPath, os.O_WRONLY|os.O_CREATE|os.O_EXCL, perm)
+		if err != nil {
+			return err
+		}
+
+		_, err = io.Copy(dst, src)
+		if closeErr := dst.Close(); err == nil {
+			err = closeErr
+		}
+		return err
+	})
+}
diff --git a/libgo/misc/cgo/testplugin/plugin_test.go b/libgo/misc/cgo/testplugin/plugin_test.go
new file mode 100644
index 00000000000..7e2b6eb04c0
--- /dev/null
+++ b/libgo/misc/cgo/testplugin/plugin_test.go
@@ -0,0 +1,203 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package plugin_test
+
+import (
+	"bytes"
+	"context"
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+	"time"
+)
+
+var gcflags string = os.Getenv("GO_GCFLAGS")
+
+func TestMain(m *testing.M) {
+	flag.Parse()
+	if testing.Short() && os.Getenv("GO_BUILDER_NAME") == "" {
+		fmt.Printf("SKIP - short mode and $GO_BUILDER_NAME not set\n")
+		os.Exit(0)
+	}
+	log.SetFlags(log.Lshortfile)
+	os.Exit(testMain(m))
+}
+
+func testMain(m *testing.M) int {
+	// Copy testdata into GOPATH/src/testarchive, along with a go.mod file
+	// declaring the same path.
+
+	GOPATH, err := ioutil.TempDir("", "plugin_test")
+	if err != nil {
+		log.Panic(err)
+	}
+	defer os.RemoveAll(GOPATH)
+
+	modRoot := filepath.Join(GOPATH, "src", "testplugin")
+	altRoot := filepath.Join(GOPATH, "alt", "src", "testplugin")
+	for srcRoot, dstRoot := range map[string]string{
+		"testdata":                           modRoot,
+		filepath.Join("altpath", "testdata"): altRoot,
+	} {
+		if err := overlayDir(dstRoot, srcRoot); err != nil {
+			log.Panic(err)
+		}
+		if err := ioutil.WriteFile(filepath.Join(dstRoot, "go.mod"), []byte("module testplugin\n"), 0666); err != nil {
+			log.Panic(err)
+		}
+	}
+
+	os.Setenv("GOPATH", filepath.Join(GOPATH, "alt"))
+	if err := os.Chdir(altRoot); err != nil {
+		log.Panic(err)
+	}
+	os.Setenv("PWD", altRoot)
+	goCmd(nil, "build", "-buildmode=plugin", "-o", filepath.Join(modRoot, "plugin-mismatch.so"), "./plugin-mismatch")
+
+	os.Setenv("GOPATH", GOPATH)
+	if err := os.Chdir(modRoot); err != nil {
+		log.Panic(err)
+	}
+	os.Setenv("PWD", modRoot)
+
+	os.Setenv("LD_LIBRARY_PATH", modRoot)
+
+	goCmd(nil, "build", "-i", "-buildmode=plugin", "./plugin1")
+	goCmd(nil, "build", "-buildmode=plugin", "./plugin2")
+	so, err := ioutil.ReadFile("plugin2.so")
+	if err != nil {
+		log.Panic(err)
+	}
+	if err := ioutil.WriteFile("plugin2-dup.so", so, 0444); err != nil {
+		log.Panic(err)
+	}
+
+	goCmd(nil, "build", "-buildmode=plugin", "-o=sub/plugin1.so", "./sub/plugin1")
+	goCmd(nil, "build", "-buildmode=plugin", "-o=unnamed1.so", "./unnamed1/main.go")
+	goCmd(nil, "build", "-buildmode=plugin", "-o=unnamed2.so", "./unnamed2/main.go")
+	goCmd(nil, "build", "-o", "host.exe", "./host")
+
+	return m.Run()
+}
+
+func goCmd(t *testing.T, op string, args ...string) {
+	if t != nil {
+		t.Helper()
+	}
+	run(t, "go", append([]string{op, "-gcflags", gcflags}, args...)...)
+}
+
+func run(t *testing.T, bin string, args ...string) string {
+	cmd := exec.Command(bin, args...)
+	cmd.Stderr = new(strings.Builder)
+	out, err := cmd.Output()
+	if err != nil {
+		if t == nil {
+			log.Panicf("%s: %v\n%s", strings.Join(cmd.Args, " "), err, cmd.Stderr)
+		} else {
+			t.Helper()
+			t.Fatalf("%s: %v\n%s", strings.Join(cmd.Args, " "), err, cmd.Stderr)
+		}
+	}
+
+	return string(bytes.TrimSpace(out))
+}
+
+func TestDWARFSections(t *testing.T) {
+	// test that DWARF sections are emitted for plugins and programs importing "plugin"
+	if runtime.GOOS != "darwin" {
+		// On macOS, for some reason, the linker doesn't add debug sections to .so,
+		// see issue #27502.
+		goCmd(t, "run", "./checkdwarf/main.go", "plugin2.so", "plugin2.UnexportedNameReuse")
+	}
+	goCmd(t, "run", "./checkdwarf/main.go", "./host.exe", "main.main")
+}
+
+func TestRunHost(t *testing.T) {
+	run(t, "./host.exe")
+}
+
+func TestUniqueTypesAndItabs(t *testing.T) {
+	goCmd(t, "build", "-buildmode=plugin", "./iface_a")
+	goCmd(t, "build", "-buildmode=plugin", "./iface_b")
+	goCmd(t, "build", "-o", "iface.exe", "./iface")
+	run(t, "./iface.exe")
+}
+
+func TestIssue18676(t *testing.T) {
+	// make sure we don't add the same itab twice.
+	// The buggy code hangs forever, so use a timeout to check for that.
+	goCmd(t, "build", "-buildmode=plugin", "-o", "plugin.so", "./issue18676/plugin.go")
+	goCmd(t, "build", "-o", "issue18676.exe", "./issue18676/main.go")
+
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	cmd := exec.CommandContext(ctx, "./issue18676.exe")
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		t.Fatalf("%s: %v\n%s", strings.Join(cmd.Args, " "), err, out)
+	}
+}
+
+func TestIssue19534(t *testing.T) {
+	// Test that we can load a plugin built in a path with non-alpha characters.
+	goCmd(t, "build", "-buildmode=plugin", "-ldflags='-pluginpath=issue.19534'", "-o", "plugin.so", "./issue19534/plugin.go")
+	goCmd(t, "build", "-o", "issue19534.exe", "./issue19534/main.go")
+	run(t, "./issue19534.exe")
+}
+
+func TestIssue18584(t *testing.T) {
+	goCmd(t, "build", "-buildmode=plugin", "-o", "plugin.so", "./issue18584/plugin.go")
+	goCmd(t, "build", "-o", "issue18584.exe", "./issue18584/main.go")
+	run(t, "./issue18584.exe")
+}
+
+func TestIssue19418(t *testing.T) {
+	goCmd(t, "build", "-buildmode=plugin", "-ldflags=-X main.Val=linkstr", "-o", "plugin.so", "./issue19418/plugin.go")
+	goCmd(t, "build", "-o", "issue19418.exe", "./issue19418/main.go")
+	run(t, "./issue19418.exe")
+}
+
+func TestIssue19529(t *testing.T) {
+	goCmd(t, "build", "-buildmode=plugin", "-o", "plugin.so", "./issue19529/plugin.go")
+}
+
+func TestIssue22175(t *testing.T) {
+	goCmd(t, "build", "-buildmode=plugin", "-o", "issue22175_plugin1.so", "./issue22175/plugin1.go")
+	goCmd(t, "build", "-buildmode=plugin", "-o", "issue22175_plugin2.so", "./issue22175/plugin2.go")
+	goCmd(t, "build", "-o", "issue22175.exe", "./issue22175/main.go")
+	run(t, "./issue22175.exe")
+}
+
+func TestIssue22295(t *testing.T) {
+	goCmd(t, "build", "-buildmode=plugin", "-o", "issue.22295.so", "./issue22295.pkg")
+	goCmd(t, "build", "-o", "issue22295.exe", "./issue22295.pkg/main.go")
+	run(t, "./issue22295.exe")
+}
+
+func TestIssue24351(t *testing.T) {
+	goCmd(t, "build", "-buildmode=plugin", "-o", "issue24351.so", "./issue24351/plugin.go")
+	goCmd(t, "build", "-o", "issue24351.exe", "./issue24351/main.go")
+	run(t, "./issue24351.exe")
+}
+
+func TestIssue25756(t *testing.T) {
+	goCmd(t, "build", "-buildmode=plugin", "-o", "life.so", "./issue25756/plugin")
+	goCmd(t, "build", "-o", "issue25756.exe", "./issue25756/main.go")
+	// Fails intermittently, but 20 runs should cause the failure
+	for n := 20; n > 0; n-- {
+		t.Run(fmt.Sprint(n), func(t *testing.T) {
+			t.Parallel()
+			run(t, "./issue25756.exe")
+		})
+	}
+}
diff --git a/libgo/misc/cgo/testplugin/test.bash b/libgo/misc/cgo/testplugin/test.bash
deleted file mode 100644
index 1b94bc4badb..00000000000
--- a/libgo/misc/cgo/testplugin/test.bash
+++ /dev/null
@@ -1,109 +0,0 @@
-#!/usr/bin/env bash
-# Copyright 2016 The Go Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style
-# license that can be found in the LICENSE file.
-
-set -e
-
-if [ ! -f src/host/host.go ]; then
-	cwd=$(pwd)
-	echo "misc/cgo/testplugin/test.bash is running in $cwd" 1>&2
-	exit 1
-fi
-
-goos=$(go env GOOS)
-goarch=$(go env GOARCH)
-
-function cleanup() {
-	rm -f plugin*.so unnamed*.so iface*.so life.so issue*
-	rm -rf host pkg sub iface
-}
-trap cleanup EXIT
-
-rm -rf pkg sub
-mkdir sub
-
-GOPATH=$(pwd) go build -i -gcflags "$GO_GCFLAGS" -buildmode=plugin plugin1
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin plugin2
-cp plugin2.so plugin2-dup.so
-GOPATH=$(pwd)/altpath go build -gcflags "$GO_GCFLAGS" -buildmode=plugin plugin-mismatch
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin -o=sub/plugin1.so sub/plugin1
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin -o=unnamed1.so unnamed1/main.go
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin -o=unnamed2.so unnamed2/main.go
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" host
-
-# test that DWARF sections are emitted for plugins and programs importing "plugin"
-if [ $GOOS != "darwin" ]; then
-	# On macOS, for some reason, the linker doesn't add debug sections to .so,
-	# see issue #27502.
-	go run src/checkdwarf/main.go plugin2.so plugin2.UnexportedNameReuse
-fi
-go run src/checkdwarf/main.go host main.main
-
-LD_LIBRARY_PATH=$(pwd) ./host
-
-# Test that types and itabs get properly uniqified.
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin iface_a
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin iface_b
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" iface
-LD_LIBRARY_PATH=$(pwd) ./iface
-
-function _timeout() (
-	set -e
-	$2 &
-	p=$!
-	(sleep $1; kill $p 2>/dev/null) &
-	p2=$!
-	wait $p 2>/dev/null
-	kill -0 $p2 2>/dev/null
-)
-
-# Test for issue 18676 - make sure we don't add the same itab twice.
-# The buggy code hangs forever, so use a timeout to check for that.
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin -o plugin.so src/issue18676/plugin.go
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -o issue18676 src/issue18676/main.go
-_timeout 10s ./issue18676
-
-# Test for issue 19534 - that we can load a plugin built in a path with non-alpha
-# characters
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin -ldflags='-pluginpath=issue.19534' -o plugin.so src/issue19534/plugin.go
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -o issue19534 src/issue19534/main.go
-./issue19534
-
-# Test for issue 18584
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin -o plugin.so src/issue18584/plugin.go
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -o issue18584 src/issue18584/main.go
-./issue18584
-
-# Test for issue 19418
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin "-ldflags=-X main.Val=linkstr" -o plugin.so src/issue19418/plugin.go
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -o issue19418 src/issue19418/main.go
-./issue19418
-
-# Test for issue 19529
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin -o plugin.so src/issue19529/plugin.go
-
-# Test for issue 22175
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin -o issue22175_plugin1.so src/issue22175/plugin1.go
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin -o issue22175_plugin2.so src/issue22175/plugin2.go
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -o issue22175 src/issue22175/main.go
-./issue22175
-
-# Test for issue 22295
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin -o issue.22295.so issue22295.pkg
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -o issue22295 src/issue22295.pkg/main.go
-./issue22295
-
-# Test for issue 24351
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin -o issue24351.so src/issue24351/plugin.go
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -o issue24351 src/issue24351/main.go
-./issue24351
-
-# Test for issue 25756
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -buildmode=plugin -o life.so issue25756/plugin
-GOPATH=$(pwd) go build -gcflags "$GO_GCFLAGS" -o issue25756 src/issue25756/main.go
-# Fails intermittently, but 20 runs should cause the failure
-for i in `seq 1 20`;
-do
-  ./issue25756 > /dev/null
-done
diff --git a/libgo/misc/cgo/testplugin/src/checkdwarf/main.go b/libgo/misc/cgo/testplugin/testdata/checkdwarf/main.go
index 7886c834e7c..7886c834e7c 100644
--- a/libgo/misc/cgo/testplugin/src/checkdwarf/main.go
+++ b/libgo/misc/cgo/testplugin/testdata/checkdwarf/main.go
diff --git a/libgo/misc/cgo/testplugin/src/common/common.go b/libgo/misc/cgo/testplugin/testdata/common/common.go
index b064e6bccfe..b064e6bccfe 100644
--- a/libgo/misc/cgo/testplugin/src/common/common.go
+++ b/libgo/misc/cgo/testplugin/testdata/common/common.go
diff --git a/libgo/misc/cgo/testplugin/src/host/host.go b/libgo/misc/cgo/testplugin/testdata/host/host.go
index 0ca17da3def..a3799328cdc 100644
--- a/libgo/misc/cgo/testplugin/src/host/host.go
+++ b/libgo/misc/cgo/testplugin/testdata/host/host.go
@@ -11,7 +11,7 @@ import (
 	"plugin"
 	"strings"
 
-	"common"
+	"testplugin/common"
 )
 
 func init() {
diff --git a/libgo/misc/cgo/testplugin/src/iface/main.go b/libgo/misc/cgo/testplugin/testdata/iface/main.go
index 5e7e4d8b480..c04f28880f5 100644
--- a/libgo/misc/cgo/testplugin/src/iface/main.go
+++ b/libgo/misc/cgo/testplugin/testdata/iface/main.go
@@ -5,9 +5,10 @@
 package main
 
 import (
-	"iface_i"
 	"log"
 	"plugin"
+
+	"testplugin/iface_i"
 )
 
 func main() {
diff --git a/libgo/misc/cgo/testplugin/src/iface_a/a.go b/libgo/misc/cgo/testplugin/testdata/iface_a/a.go
index 29d2e277640..357f7e827ed 100644
--- a/libgo/misc/cgo/testplugin/src/iface_a/a.go
+++ b/libgo/misc/cgo/testplugin/testdata/iface_a/a.go
@@ -4,7 +4,7 @@
 
 package main
 
-import "iface_i"
+import "testplugin/iface_i"
 
 //go:noinline
 func F() interface{} {
diff --git a/libgo/misc/cgo/testplugin/src/iface_b/b.go b/libgo/misc/cgo/testplugin/testdata/iface_b/b.go
index 29d2e277640..357f7e827ed 100644
--- a/libgo/misc/cgo/testplugin/src/iface_b/b.go
+++ b/libgo/misc/cgo/testplugin/testdata/iface_b/b.go
@@ -4,7 +4,7 @@
 
 package main
 
-import "iface_i"
+import "testplugin/iface_i"
 
 //go:noinline
 func F() interface{} {
diff --git a/libgo/misc/cgo/testplugin/src/iface_i/i.go b/libgo/misc/cgo/testplugin/testdata/iface_i/i.go
index 31c80387c7e..31c80387c7e 100644
--- a/libgo/misc/cgo/testplugin/src/iface_i/i.go
+++ b/libgo/misc/cgo/testplugin/testdata/iface_i/i.go
diff --git a/libgo/misc/cgo/testplugin/src/issue18584/main.go b/libgo/misc/cgo/testplugin/testdata/issue18584/main.go
index c280fd46203..c280fd46203 100644
--- a/libgo/misc/cgo/testplugin/src/issue18584/main.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue18584/main.go
diff --git a/libgo/misc/cgo/testplugin/src/issue18584/plugin.go b/libgo/misc/cgo/testplugin/testdata/issue18584/plugin.go
index be0868d3752..be0868d3752 100644
--- a/libgo/misc/cgo/testplugin/src/issue18584/plugin.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue18584/plugin.go
diff --git a/libgo/misc/cgo/testplugin/src/issue18676/dynamodbstreamsevt/definition.go b/libgo/misc/cgo/testplugin/testdata/issue18676/dynamodbstreamsevt/definition.go
index 70fd054d089..70fd054d089 100644
--- a/libgo/misc/cgo/testplugin/src/issue18676/dynamodbstreamsevt/definition.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue18676/dynamodbstreamsevt/definition.go
diff --git a/libgo/misc/cgo/testplugin/src/issue18676/main.go b/libgo/misc/cgo/testplugin/testdata/issue18676/main.go
index c75409dafe7..b1dadbedf22 100644
--- a/libgo/misc/cgo/testplugin/src/issue18676/main.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue18676/main.go
@@ -17,8 +17,8 @@ package main
 
 import (
 	"encoding/json"
-	"issue18676/dynamodbstreamsevt"
 	"plugin"
+	"testplugin/issue18676/dynamodbstreamsevt"
 )
 
 func main() {
diff --git a/libgo/misc/cgo/testplugin/src/issue18676/plugin.go b/libgo/misc/cgo/testplugin/testdata/issue18676/plugin.go
index 8a3b85a75cd..e7fc74f7774 100644
--- a/libgo/misc/cgo/testplugin/src/issue18676/plugin.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue18676/plugin.go
@@ -6,6 +6,6 @@ package main
 
 import "C"
 
-import "issue18676/dynamodbstreamsevt"
+import "testplugin/issue18676/dynamodbstreamsevt"
 
 func F(evt *dynamodbstreamsevt.Event) {}
diff --git a/libgo/misc/cgo/testplugin/src/issue19418/main.go b/libgo/misc/cgo/testplugin/testdata/issue19418/main.go
index 2ec9f9aaaa2..2ec9f9aaaa2 100644
--- a/libgo/misc/cgo/testplugin/src/issue19418/main.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue19418/main.go
diff --git a/libgo/misc/cgo/testplugin/src/issue19418/plugin.go b/libgo/misc/cgo/testplugin/testdata/issue19418/plugin.go
index fe93b161431..fe93b161431 100644
--- a/libgo/misc/cgo/testplugin/src/issue19418/plugin.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue19418/plugin.go
diff --git a/libgo/misc/cgo/testplugin/src/issue19529/plugin.go b/libgo/misc/cgo/testplugin/testdata/issue19529/plugin.go
index ad2df6cc7c7..ad2df6cc7c7 100644
--- a/libgo/misc/cgo/testplugin/src/issue19529/plugin.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue19529/plugin.go
diff --git a/libgo/misc/cgo/testplugin/src/issue19534/main.go b/libgo/misc/cgo/testplugin/testdata/issue19534/main.go
index de263b6f0f2..de263b6f0f2 100644
--- a/libgo/misc/cgo/testplugin/src/issue19534/main.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue19534/main.go
diff --git a/libgo/misc/cgo/testplugin/src/issue19534/plugin.go b/libgo/misc/cgo/testplugin/testdata/issue19534/plugin.go
index 582d33305c9..582d33305c9 100644
--- a/libgo/misc/cgo/testplugin/src/issue19534/plugin.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue19534/plugin.go
diff --git a/libgo/misc/cgo/testplugin/src/issue22175/main.go b/libgo/misc/cgo/testplugin/testdata/issue22175/main.go
index 9be9bab9dc3..9be9bab9dc3 100644
--- a/libgo/misc/cgo/testplugin/src/issue22175/main.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue22175/main.go
diff --git a/libgo/misc/cgo/testplugin/src/issue22175/plugin1.go b/libgo/misc/cgo/testplugin/testdata/issue22175/plugin1.go
index 5ae6cb631e7..5ae6cb631e7 100644
--- a/libgo/misc/cgo/testplugin/src/issue22175/plugin1.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue22175/plugin1.go
diff --git a/libgo/misc/cgo/testplugin/src/issue22175/plugin2.go b/libgo/misc/cgo/testplugin/testdata/issue22175/plugin2.go
index f387a192e67..f387a192e67 100644
--- a/libgo/misc/cgo/testplugin/src/issue22175/plugin2.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue22175/plugin2.go
diff --git a/libgo/misc/cgo/testplugin/src/issue22295.pkg/main.go b/libgo/misc/cgo/testplugin/testdata/issue22295.pkg/main.go
index 6cb186e1003..6cb186e1003 100644
--- a/libgo/misc/cgo/testplugin/src/issue22295.pkg/main.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue22295.pkg/main.go
diff --git a/libgo/misc/cgo/testplugin/src/issue22295.pkg/plugin.go b/libgo/misc/cgo/testplugin/testdata/issue22295.pkg/plugin.go
index 46b08a405bc..46b08a405bc 100644
--- a/libgo/misc/cgo/testplugin/src/issue22295.pkg/plugin.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue22295.pkg/plugin.go
diff --git a/libgo/misc/cgo/testplugin/src/issue24351/main.go b/libgo/misc/cgo/testplugin/testdata/issue24351/main.go
index 4107adff7b4..4107adff7b4 100644
--- a/libgo/misc/cgo/testplugin/src/issue24351/main.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue24351/main.go
diff --git a/libgo/misc/cgo/testplugin/src/issue24351/plugin.go b/libgo/misc/cgo/testplugin/testdata/issue24351/plugin.go
index db17e0a6097..db17e0a6097 100644
--- a/libgo/misc/cgo/testplugin/src/issue24351/plugin.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue24351/plugin.go
diff --git a/libgo/misc/cgo/testplugin/src/issue25756/main.go b/libgo/misc/cgo/testplugin/testdata/issue25756/main.go
index 817daf42f68..817daf42f68 100644
--- a/libgo/misc/cgo/testplugin/src/issue25756/main.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue25756/main.go
diff --git a/libgo/misc/cgo/testplugin/src/issue25756/plugin/c-life.c b/libgo/misc/cgo/testplugin/testdata/issue25756/plugin/c-life.c
index f853163e2f0..f853163e2f0 100644
--- a/libgo/misc/cgo/testplugin/src/issue25756/plugin/c-life.c
+++ b/libgo/misc/cgo/testplugin/testdata/issue25756/plugin/c-life.c
diff --git a/libgo/misc/cgo/testplugin/src/issue25756/plugin/life.go b/libgo/misc/cgo/testplugin/testdata/issue25756/plugin/life.go
index 675a192fc10..675a192fc10 100644
--- a/libgo/misc/cgo/testplugin/src/issue25756/plugin/life.go
+++ b/libgo/misc/cgo/testplugin/testdata/issue25756/plugin/life.go
diff --git a/libgo/misc/cgo/testplugin/src/issue25756/plugin/life.h b/libgo/misc/cgo/testplugin/testdata/issue25756/plugin/life.h
index 11d2b972267..11d2b972267 100644
--- a/libgo/misc/cgo/testplugin/src/issue25756/plugin/life.h
+++ b/libgo/misc/cgo/testplugin/testdata/issue25756/plugin/life.h
diff --git a/libgo/misc/cgo/testplugin/src/plugin1/plugin1.go b/libgo/misc/cgo/testplugin/testdata/plugin1/plugin1.go
index 0a9fa2f2c1f..d29d674ade0 100644
--- a/libgo/misc/cgo/testplugin/src/plugin1/plugin1.go
+++ b/libgo/misc/cgo/testplugin/testdata/plugin1/plugin1.go
@@ -8,8 +8,9 @@ package main
 import "C"
 
 import (
-	"common"
 	"reflect"
+
+	"testplugin/common"
 )
 
 func F() int {
diff --git a/libgo/misc/cgo/testplugin/src/plugin2/plugin2.go b/libgo/misc/cgo/testplugin/testdata/plugin2/plugin2.go
index a67f2de27a7..31ed642ca5b 100644
--- a/libgo/misc/cgo/testplugin/src/plugin2/plugin2.go
+++ b/libgo/misc/cgo/testplugin/testdata/plugin2/plugin2.go
@@ -12,9 +12,10 @@ import "C"
 // void cfunc() {} // uses cgo_topofstack
 
 import (
-	"common"
 	"reflect"
 	"strings"
+
+	"testplugin/common"
 )
 
 func init() {
diff --git a/libgo/misc/cgo/testplugin/src/sub/plugin1/plugin1.go b/libgo/misc/cgo/testplugin/testdata/sub/plugin1/plugin1.go
index cf9000c4a4e..5f891b09a33 100644
--- a/libgo/misc/cgo/testplugin/src/sub/plugin1/plugin1.go
+++ b/libgo/misc/cgo/testplugin/testdata/sub/plugin1/plugin1.go
@@ -7,7 +7,7 @@ package main
 // // No C code required.
 import "C"
 
-import "common"
+import "testplugin/common"
 
 func F() int { return 17 }
 
diff --git a/libgo/misc/cgo/testplugin/unnamed1/main.go b/libgo/misc/cgo/testplugin/testdata/unnamed1/main.go
index caf09c9e890..dd1777b4184 100644
--- a/libgo/misc/cgo/testplugin/unnamed1/main.go
+++ b/libgo/misc/cgo/testplugin/testdata/unnamed1/main.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build ignore
+
 package main
 
 // // No C code required.
diff --git a/libgo/misc/cgo/testplugin/unnamed2/main.go b/libgo/misc/cgo/testplugin/testdata/unnamed2/main.go
index 7ef66109c5c..757436f250b 100644
--- a/libgo/misc/cgo/testplugin/unnamed2/main.go
+++ b/libgo/misc/cgo/testplugin/testdata/unnamed2/main.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build ignore
+
 package main
 
 // // No C code required.
diff --git a/libgo/misc/cgo/testsanitizers/cc_test.go b/libgo/misc/cgo/testsanitizers/cc_test.go
index 218e2254295..0192a663ddd 100644
--- a/libgo/misc/cgo/testsanitizers/cc_test.go
+++ b/libgo/misc/cgo/testsanitizers/cc_test.go
@@ -394,7 +394,7 @@ func (c *config) checkRuntime() (skip bool, err error) {
 
 // srcPath returns the path to the given file relative to this test's source tree.
 func srcPath(path string) string {
-	return filepath.Join("src", path)
+	return filepath.Join("testdata", path)
 }
 
 // A tempDir manages a temporary directory within a test.
diff --git a/libgo/misc/cgo/testsanitizers/src/msan.go b/libgo/misc/cgo/testsanitizers/testdata/msan.go
index 7915fa84f60..7915fa84f60 100644
--- a/libgo/misc/cgo/testsanitizers/src/msan.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/msan.go
diff --git a/libgo/misc/cgo/testsanitizers/src/msan2.go b/libgo/misc/cgo/testsanitizers/testdata/msan2.go
index 6690cb034fc..6690cb034fc 100644
--- a/libgo/misc/cgo/testsanitizers/src/msan2.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/msan2.go
diff --git a/libgo/misc/cgo/testsanitizers/src/msan2_cmsan.go b/libgo/misc/cgo/testsanitizers/testdata/msan2_cmsan.go
index 8fdaea90c97..8fdaea90c97 100644
--- a/libgo/misc/cgo/testsanitizers/src/msan2_cmsan.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/msan2_cmsan.go
diff --git a/libgo/misc/cgo/testsanitizers/src/msan3.go b/libgo/misc/cgo/testsanitizers/testdata/msan3.go
index 61a9c29e1a9..61a9c29e1a9 100644
--- a/libgo/misc/cgo/testsanitizers/src/msan3.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/msan3.go
diff --git a/libgo/misc/cgo/testsanitizers/src/msan4.go b/libgo/misc/cgo/testsanitizers/testdata/msan4.go
index 6c91ff5f091..6c91ff5f091 100644
--- a/libgo/misc/cgo/testsanitizers/src/msan4.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/msan4.go
diff --git a/libgo/misc/cgo/testsanitizers/src/msan5.go b/libgo/misc/cgo/testsanitizers/testdata/msan5.go
index f1479eb8a00..f1479eb8a00 100644
--- a/libgo/misc/cgo/testsanitizers/src/msan5.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/msan5.go
diff --git a/libgo/misc/cgo/testsanitizers/src/msan6.go b/libgo/misc/cgo/testsanitizers/testdata/msan6.go
index 003989c2bea..003989c2bea 100644
--- a/libgo/misc/cgo/testsanitizers/src/msan6.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/msan6.go
diff --git a/libgo/misc/cgo/testsanitizers/src/msan_fail.go b/libgo/misc/cgo/testsanitizers/testdata/msan_fail.go
index 4c8dab34f6e..4c8dab34f6e 100644
--- a/libgo/misc/cgo/testsanitizers/src/msan_fail.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/msan_fail.go
diff --git a/libgo/misc/cgo/testsanitizers/src/msan_shared.go b/libgo/misc/cgo/testsanitizers/testdata/msan_shared.go
index 966947cac35..966947cac35 100644
--- a/libgo/misc/cgo/testsanitizers/src/msan_shared.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/msan_shared.go
diff --git a/libgo/misc/cgo/testsanitizers/src/tsan.go b/libgo/misc/cgo/testsanitizers/testdata/tsan.go
index 6c377a701fb..6c377a701fb 100644
--- a/libgo/misc/cgo/testsanitizers/src/tsan.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/tsan.go
diff --git a/libgo/misc/cgo/testsanitizers/src/tsan10.go b/libgo/misc/cgo/testsanitizers/testdata/tsan10.go
index a40f2455537..a40f2455537 100644
--- a/libgo/misc/cgo/testsanitizers/src/tsan10.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/tsan10.go
diff --git a/libgo/misc/cgo/testsanitizers/src/tsan11.go b/libgo/misc/cgo/testsanitizers/testdata/tsan11.go
index 70ac9c8ae2c..70ac9c8ae2c 100644
--- a/libgo/misc/cgo/testsanitizers/src/tsan11.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/tsan11.go
diff --git a/libgo/misc/cgo/testsanitizers/src/tsan12.go b/libgo/misc/cgo/testsanitizers/testdata/tsan12.go
index 3e767eee1f8..3e767eee1f8 100644
--- a/libgo/misc/cgo/testsanitizers/src/tsan12.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/tsan12.go
diff --git a/libgo/misc/cgo/testsanitizers/src/tsan2.go b/libgo/misc/cgo/testsanitizers/testdata/tsan2.go
index 5018a1987ca..5018a1987ca 100644
--- a/libgo/misc/cgo/testsanitizers/src/tsan2.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/tsan2.go
diff --git a/libgo/misc/cgo/testsanitizers/src/tsan3.go b/libgo/misc/cgo/testsanitizers/testdata/tsan3.go
index 87f6c80f1b1..87f6c80f1b1 100644
--- a/libgo/misc/cgo/testsanitizers/src/tsan3.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/tsan3.go
diff --git a/libgo/misc/cgo/testsanitizers/src/tsan4.go b/libgo/misc/cgo/testsanitizers/testdata/tsan4.go
index f0c76d84116..f0c76d84116 100644
--- a/libgo/misc/cgo/testsanitizers/src/tsan4.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/tsan4.go
diff --git a/libgo/misc/cgo/testsanitizers/src/tsan5.go b/libgo/misc/cgo/testsanitizers/testdata/tsan5.go
index 1214a7743b6..1214a7743b6 100644
--- a/libgo/misc/cgo/testsanitizers/src/tsan5.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/tsan5.go
diff --git a/libgo/misc/cgo/testsanitizers/src/tsan6.go b/libgo/misc/cgo/testsanitizers/testdata/tsan6.go
index c96f08d2f37..c96f08d2f37 100644
--- a/libgo/misc/cgo/testsanitizers/src/tsan6.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/tsan6.go
diff --git a/libgo/misc/cgo/testsanitizers/src/tsan7.go b/libgo/misc/cgo/testsanitizers/testdata/tsan7.go
index 2fb9e45ee2d..2fb9e45ee2d 100644
--- a/libgo/misc/cgo/testsanitizers/src/tsan7.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/tsan7.go
diff --git a/libgo/misc/cgo/testsanitizers/src/tsan8.go b/libgo/misc/cgo/testsanitizers/testdata/tsan8.go
index 88d82a60789..88d82a60789 100644
--- a/libgo/misc/cgo/testsanitizers/src/tsan8.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/tsan8.go
diff --git a/libgo/misc/cgo/testsanitizers/src/tsan9.go b/libgo/misc/cgo/testsanitizers/testdata/tsan9.go
index f166d8b495a..f166d8b495a 100644
--- a/libgo/misc/cgo/testsanitizers/src/tsan9.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/tsan9.go
diff --git a/libgo/misc/cgo/testsanitizers/src/tsan_shared.go b/libgo/misc/cgo/testsanitizers/testdata/tsan_shared.go
index 55ff67ecbaf..55ff67ecbaf 100644
--- a/libgo/misc/cgo/testsanitizers/src/tsan_shared.go
+++ b/libgo/misc/cgo/testsanitizers/testdata/tsan_shared.go
diff --git a/libgo/misc/cgo/testsanitizers/tsan_test.go b/libgo/misc/cgo/testsanitizers/tsan_test.go
index 1d769a98b6e..ec4e0033fb4 100644
--- a/libgo/misc/cgo/testsanitizers/tsan_test.go
+++ b/libgo/misc/cgo/testsanitizers/tsan_test.go
@@ -5,15 +5,11 @@
 package sanitizers_test
 
 import (
-	"runtime"
 	"strings"
 	"testing"
 )
 
 func TestTSAN(t *testing.T) {
-	if runtime.GOARCH == "arm64" {
-		t.Skip("skipping test; see https://golang.org/issue/25682")
-	}
 	t.Parallel()
 	requireOvercommit(t)
 	config := configure("thread")
diff --git a/libgo/misc/cgo/testshared/overlaydir_test.go b/libgo/misc/cgo/testshared/overlaydir_test.go
new file mode 100644
index 00000000000..68be0562567
--- /dev/null
+++ b/libgo/misc/cgo/testshared/overlaydir_test.go
@@ -0,0 +1,81 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package shared_test
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// overlayDir makes a minimal-overhead copy of srcRoot in which new files may be added.
+//
+// TODO: Once we no longer need to support the misc module in GOPATH mode,
+// factor this function out into a package to reduce duplication.
+func overlayDir(dstRoot, srcRoot string) error {
+	dstRoot = filepath.Clean(dstRoot)
+	if err := os.MkdirAll(dstRoot, 0777); err != nil {
+		return err
+	}
+
+	symBase, err := filepath.Rel(srcRoot, dstRoot)
+	if err != nil {
+		symBase, err = filepath.Abs(srcRoot)
+		if err != nil {
+			return err
+		}
+	}
+
+	return filepath.Walk(srcRoot, func(srcPath string, info os.FileInfo, err error) error {
+		if err != nil || srcPath == srcRoot {
+			return err
+		}
+
+		suffix := strings.TrimPrefix(srcPath, srcRoot)
+		for len(suffix) > 0 && suffix[0] == filepath.Separator {
+			suffix = suffix[1:]
+		}
+		dstPath := filepath.Join(dstRoot, suffix)
+
+		perm := info.Mode() & os.ModePerm
+		if info.Mode()&os.ModeSymlink != 0 {
+			info, err = os.Stat(srcPath)
+			if err != nil {
+				return err
+			}
+			perm = info.Mode() & os.ModePerm
+		}
+
+		// Always copy directories (don't symlink them).
+		// If we add a file in the overlay, we don't want to add it in the original.
+		if info.IsDir() {
+			return os.Mkdir(dstPath, perm)
+		}
+
+		// If the OS supports symlinks, use them instead of copying bytes.
+		if err := os.Symlink(filepath.Join(symBase, suffix), dstPath); err == nil {
+			return nil
+		}
+
+		// Otherwise, copy the bytes.
+		src, err := os.Open(srcPath)
+		if err != nil {
+			return err
+		}
+		defer src.Close()
+
+		dst, err := os.OpenFile(dstPath, os.O_WRONLY|os.O_CREATE|os.O_EXCL, perm)
+		if err != nil {
+			return err
+		}
+
+		_, err = io.Copy(dst, src)
+		if closeErr := dst.Close(); err == nil {
+			err = closeErr
+		}
+		return err
+	})
+}
diff --git a/libgo/misc/cgo/testshared/shared_test.go b/libgo/misc/cgo/testshared/shared_test.go
index 41a24efe22c..ac1a1c7f1a8 100644
--- a/libgo/misc/cgo/testshared/shared_test.go
+++ b/libgo/misc/cgo/testshared/shared_test.go
@@ -44,31 +44,35 @@ func run(t *testing.T, msg string, args ...string) {
 
 // goCmd invokes the go tool with the installsuffix set up by TestMain. It calls
 // t.Fatalf if the command fails.
-func goCmd(t *testing.T, args ...string) {
+func goCmd(t *testing.T, args ...string) string {
 	newargs := []string{args[0], "-installsuffix=" + suffix}
 	if testing.Verbose() {
 		newargs = append(newargs, "-x")
 	}
 	newargs = append(newargs, args[1:]...)
 	c := exec.Command("go", newargs...)
+
+	stderr := new(strings.Builder)
 	var output []byte
 	var err error
 	if testing.Verbose() {
-		fmt.Printf("+ go %s\n", strings.Join(newargs, " "))
-		c.Stdout = os.Stdout
+		fmt.Printf("+ go %s\n", strings.Join(args, " "))
 		c.Stderr = os.Stderr
-		err = c.Run()
-		output = []byte("(output above)")
+		stderr.WriteString("(output above)")
 	} else {
-		output, err = c.CombinedOutput()
+		c.Stderr = stderr
 	}
+	output, err = c.Output()
+
 	if err != nil {
 		if t != nil {
-			t.Fatalf("executing %s failed %v:\n%s", strings.Join(c.Args, " "), err, output)
+			t.Helper()
+			t.Fatalf("executing %s failed %v:\n%s", strings.Join(c.Args, " "), err, stderr)
 		} else {
-			log.Fatalf("executing %s failed %v:\n%s", strings.Join(c.Args, " "), err, output)
+			log.Fatalf("executing %s failed %v:\n%s", strings.Join(c.Args, " "), err, stderr)
 		}
 	}
+	return string(bytes.TrimSpace(output))
 }
 
 // TestMain calls testMain so that the latter can use defer (TestMain exits with os.Exit).
@@ -105,47 +109,33 @@ func testMain(m *testing.M) (int, error) {
 
 	// Some tests need to edit the source in GOPATH, so copy this directory to a
 	// temporary directory and chdir to that.
-	scratchDir, err := ioutil.TempDir("", "testshared")
+	gopath, err := ioutil.TempDir("", "testshared")
 	if err != nil {
 		return 0, fmt.Errorf("TempDir failed: %v", err)
 	}
 	if testing.Verbose() {
-		fmt.Printf("+ mkdir -p %s\n", scratchDir)
-	}
-	defer os.RemoveAll(scratchDir)
-	err = filepath.Walk(".", func(path string, info os.FileInfo, err error) error {
-		scratchPath := filepath.Join(scratchDir, path)
-		if info.IsDir() {
-			if path == "." {
-				return nil
-			}
-			if testing.Verbose() {
-				fmt.Printf("+ mkdir -p %s\n", scratchPath)
-			}
-			return os.Mkdir(scratchPath, info.Mode())
-		} else {
-			fromBytes, err := ioutil.ReadFile(path)
-			if err != nil {
-				return err
-			}
-			if testing.Verbose() {
-				fmt.Printf("+ cp %s %s\n", path, scratchPath)
-			}
-			return ioutil.WriteFile(scratchPath, fromBytes, info.Mode())
-		}
-	})
-	if err != nil {
-		return 0, fmt.Errorf("walk failed: %v", err)
+		fmt.Printf("+ mkdir -p %s\n", gopath)
+	}
+	defer os.RemoveAll(gopath)
+
+	modRoot := filepath.Join(gopath, "src", "testshared")
+	if err := overlayDir(modRoot, "testdata"); err != nil {
+		return 0, err
 	}
-	os.Setenv("GOPATH", scratchDir)
 	if testing.Verbose() {
-		fmt.Printf("+ export GOPATH=%s\n", scratchDir)
+		fmt.Printf("+ cd %s\n", modRoot)
+	}
+	os.Chdir(modRoot)
+	os.Setenv("PWD", modRoot)
+	if err := ioutil.WriteFile("go.mod", []byte("module testshared\n"), 0666); err != nil {
+		return 0, err
 	}
-	myContext.GOPATH = scratchDir
+
+	os.Setenv("GOPATH", gopath)
 	if testing.Verbose() {
-		fmt.Printf("+ cd %s\n", scratchDir)
+		fmt.Printf("+ export GOPATH=%s\n", gopath)
 	}
-	os.Chdir(scratchDir)
+	myContext.GOPATH = gopath
 
 	// All tests depend on runtime being built into a shared library. Because
 	// that takes a few seconds, do it here and have all tests use the version
@@ -154,15 +144,20 @@ func testMain(m *testing.M) (int, error) {
 	goCmd(nil, append([]string{"install", "-buildmode=shared"}, minpkgs...)...)
 
 	myContext.InstallSuffix = suffix + "_dynlink"
-	depP, err := myContext.Import("depBase", ".", build.ImportComment)
+	depP, err := myContext.Import("./depBase", ".", build.ImportComment)
 	if err != nil {
 		return 0, fmt.Errorf("import failed: %v", err)
 	}
-	gopathInstallDir = depP.PkgTargetRoot
+	if depP.PkgTargetRoot == "" {
+		gopathInstallDir = filepath.Dir(goCmd(nil, "list", "-buildmode=shared", "-f", "{{.Target}}", "./depBase"))
+	} else {
+		gopathInstallDir = filepath.Join(depP.PkgTargetRoot, "testshared")
+	}
 	return m.Run(), nil
 }
 
 func TestMain(m *testing.M) {
+	log.SetFlags(log.Lshortfile)
 	flag.Parse()
 
 	// Some of the tests install binaries into a custom GOPATH.
@@ -350,6 +345,7 @@ func readNotes(f *elf.File) ([]*note, error) {
 }
 
 func dynStrings(t *testing.T, path string, flag elf.DynTag) []string {
+	t.Helper()
 	f, err := elf.Open(path)
 	if err != nil {
 		t.Fatalf("elf.Open(%q) failed: %v", path, err)
@@ -363,6 +359,7 @@ func dynStrings(t *testing.T, path string, flag elf.DynTag) []string {
 }
 
 func AssertIsLinkedToRegexp(t *testing.T, path string, re *regexp.Regexp) {
+	t.Helper()
 	for _, dynstring := range dynStrings(t, path, elf.DT_NEEDED) {
 		if re.MatchString(dynstring) {
 			return
@@ -372,10 +369,12 @@ func AssertIsLinkedToRegexp(t *testing.T, path string, re *regexp.Regexp) {
 }
 
 func AssertIsLinkedTo(t *testing.T, path, lib string) {
+	t.Helper()
 	AssertIsLinkedToRegexp(t, path, regexp.MustCompile(regexp.QuoteMeta(lib)))
 }
 
 func AssertHasRPath(t *testing.T, path, dir string) {
+	t.Helper()
 	for _, tag := range []elf.DynTag{elf.DT_RPATH, elf.DT_RUNPATH} {
 		for _, dynstring := range dynStrings(t, path, tag) {
 			for _, rpath := range strings.Split(dynstring, ":") {
@@ -390,15 +389,15 @@ func AssertHasRPath(t *testing.T, path, dir string) {
 
 // Build a trivial program that links against the shared runtime and check it runs.
 func TestTrivialExecutable(t *testing.T) {
-	goCmd(t, "install", "-linkshared", "trivial")
-	run(t, "trivial executable", "./bin/trivial")
-	AssertIsLinkedTo(t, "./bin/trivial", soname)
-	AssertHasRPath(t, "./bin/trivial", gorootInstallDir)
+	goCmd(t, "install", "-linkshared", "./trivial")
+	run(t, "trivial executable", "../../bin/trivial")
+	AssertIsLinkedTo(t, "../../bin/trivial", soname)
+	AssertHasRPath(t, "../../bin/trivial", gorootInstallDir)
 }
 
 // Build a trivial program in PIE mode that links against the shared runtime and check it runs.
 func TestTrivialExecutablePIE(t *testing.T) {
-	goCmd(t, "build", "-buildmode=pie", "-o", "trivial.pie", "-linkshared", "trivial")
+	goCmd(t, "build", "-buildmode=pie", "-o", "trivial.pie", "-linkshared", "./trivial")
 	run(t, "trivial executable", "./trivial.pie")
 	AssertIsLinkedTo(t, "./trivial.pie", soname)
 	AssertHasRPath(t, "./trivial.pie", gorootInstallDir)
@@ -406,15 +405,15 @@ func TestTrivialExecutablePIE(t *testing.T) {
 
 // Build a division test program and check it runs.
 func TestDivisionExecutable(t *testing.T) {
-	goCmd(t, "install", "-linkshared", "division")
-	run(t, "division executable", "./bin/division")
+	goCmd(t, "install", "-linkshared", "./division")
+	run(t, "division executable", "../../bin/division")
 }
 
 // Build an executable that uses cgo linked against the shared runtime and check it
 // runs.
 func TestCgoExecutable(t *testing.T) {
-	goCmd(t, "install", "-linkshared", "execgo")
-	run(t, "cgo executable", "./bin/execgo")
+	goCmd(t, "install", "-linkshared", "./execgo")
+	run(t, "cgo executable", "../../bin/execgo")
 }
 
 func checkPIE(t *testing.T, name string) {
@@ -433,7 +432,7 @@ func checkPIE(t *testing.T, name string) {
 
 func TestTrivialPIE(t *testing.T) {
 	name := "trivial_pie"
-	goCmd(t, "build", "-buildmode=pie", "-o="+name, "trivial")
+	goCmd(t, "build", "-buildmode=pie", "-o="+name, "./trivial")
 	defer os.Remove(name)
 	run(t, name, "./"+name)
 	checkPIE(t, name)
@@ -441,7 +440,7 @@ func TestTrivialPIE(t *testing.T) {
 
 func TestCgoPIE(t *testing.T) {
 	name := "cgo_pie"
-	goCmd(t, "build", "-buildmode=pie", "-o="+name, "execgo")
+	goCmd(t, "build", "-buildmode=pie", "-o="+name, "./execgo")
 	defer os.Remove(name)
 	run(t, name, "./"+name)
 	checkPIE(t, name)
@@ -450,15 +449,16 @@ func TestCgoPIE(t *testing.T) {
 // Build a GOPATH package into a shared library that links against the goroot runtime
 // and an executable that links against both.
 func TestGopathShlib(t *testing.T) {
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
-	AssertIsLinkedTo(t, filepath.Join(gopathInstallDir, "libdepBase.so"), soname)
-	goCmd(t, "install", "-linkshared", "exe")
-	AssertIsLinkedTo(t, "./bin/exe", soname)
-	AssertIsLinkedTo(t, "./bin/exe", "libdepBase.so")
-	AssertHasRPath(t, "./bin/exe", gorootInstallDir)
-	AssertHasRPath(t, "./bin/exe", gopathInstallDir)
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./depBase")
+	shlib := goCmd(t, "list", "-f", "{{.Shlib}}", "-buildmode=shared", "-linkshared", "./depBase")
+	AssertIsLinkedTo(t, shlib, soname)
+	goCmd(t, "install", "-linkshared", "./exe")
+	AssertIsLinkedTo(t, "../../bin/exe", soname)
+	AssertIsLinkedTo(t, "../../bin/exe", filepath.Base(shlib))
+	AssertHasRPath(t, "../../bin/exe", gorootInstallDir)
+	AssertHasRPath(t, "../../bin/exe", filepath.Dir(gopathInstallDir))
 	// And check it runs.
-	run(t, "executable linked to GOPATH library", "./bin/exe")
+	run(t, "executable linked to GOPATH library", "../../bin/exe")
 }
 
 // The shared library contains a note listing the packages it contains in a section
@@ -470,8 +470,8 @@ func testPkgListNote(t *testing.T, f *elf.File, note *note) {
 	if isOffsetLoaded(f, note.section.Offset) {
 		t.Errorf("package list section contained in PT_LOAD segment")
 	}
-	if note.desc != "depBase\n" {
-		t.Errorf("incorrect package list %q, want %q", note.desc, "depBase\n")
+	if note.desc != "testshared/depBase\n" {
+		t.Errorf("incorrect package list %q, want %q", note.desc, "testshared/depBase\n")
 	}
 }
 
@@ -528,8 +528,9 @@ func testDepsNote(t *testing.T, f *elf.File, note *note) {
 
 // The shared library contains notes with defined contents; see above.
 func TestNotes(t *testing.T) {
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
-	f, err := elf.Open(filepath.Join(gopathInstallDir, "libdepBase.so"))
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./depBase")
+	shlib := goCmd(t, "list", "-f", "{{.Shlib}}", "-buildmode=shared", "-linkshared", "./depBase")
+	f, err := elf.Open(shlib)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -581,23 +582,24 @@ func TestNotes(t *testing.T) {
 // runtime, another package (dep2) that links against the first, and an
 // executable that links against dep2.
 func TestTwoGopathShlibs(t *testing.T) {
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "dep2")
-	goCmd(t, "install", "-linkshared", "exe2")
-	run(t, "executable linked to GOPATH library", "./bin/exe2")
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./depBase")
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./dep2")
+	goCmd(t, "install", "-linkshared", "./exe2")
+	run(t, "executable linked to GOPATH library", "../../bin/exe2")
 }
 
 func TestThreeGopathShlibs(t *testing.T) {
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "dep2")
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "dep3")
-	goCmd(t, "install", "-linkshared", "exe3")
-	run(t, "executable linked to GOPATH library", "./bin/exe3")
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./depBase")
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./dep2")
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./dep3")
+	goCmd(t, "install", "-linkshared", "./exe3")
+	run(t, "executable linked to GOPATH library", "../../bin/exe3")
 }
 
-// If gccgo is not available or not new enough call t.Skip. Otherwise,
-// return a build.Context that is set up for gccgo.
-func prepGccgo(t *testing.T) build.Context {
+// If gccgo is not available or not new enough, call t.Skip.
+func requireGccgo(t *testing.T) {
+	t.Helper()
+
 	gccgoName := os.Getenv("GCCGO")
 	if gccgoName == "" {
 		gccgoName = "gccgo"
@@ -614,61 +616,64 @@ func prepGccgo(t *testing.T) build.Context {
 	if string(output) < "5" {
 		t.Skipf("gccgo too old (%s)", strings.TrimSpace(string(output)))
 	}
-	gccgoContext := build.Default
-	gccgoContext.InstallSuffix = suffix + "_fPIC"
-	gccgoContext.Compiler = "gccgo"
-	gccgoContext.GOPATH = os.Getenv("GOPATH")
-	return gccgoContext
+
+	gomod, err := exec.Command("go", "env", "GOMOD").Output()
+	if err != nil {
+		t.Fatalf("go env GOMOD: %v", err)
+	}
+	if len(bytes.TrimSpace(gomod)) > 0 {
+		t.Skipf("gccgo not supported in module mode; see golang.org/issue/30344")
+	}
 }
 
 // Build a GOPATH package into a shared library with gccgo and an executable that
 // links against it.
 func TestGoPathShlibGccgo(t *testing.T) {
-	gccgoContext := prepGccgo(t)
+	requireGccgo(t)
 
 	libgoRE := regexp.MustCompile("libgo.so.[0-9]+")
 
-	depP, err := gccgoContext.Import("depBase", ".", build.ImportComment)
-	if err != nil {
-		t.Fatalf("import failed: %v", err)
-	}
-	gccgoInstallDir := filepath.Join(depP.PkgTargetRoot, "shlibs")
-	goCmd(t, "install", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "depBase")
-	AssertIsLinkedToRegexp(t, filepath.Join(gccgoInstallDir, "libdepBase.so"), libgoRE)
-	goCmd(t, "install", "-compiler=gccgo", "-linkshared", "exe")
-	AssertIsLinkedToRegexp(t, "./bin/exe", libgoRE)
-	AssertIsLinkedTo(t, "./bin/exe", "libdepBase.so")
-	AssertHasRPath(t, "./bin/exe", gccgoInstallDir)
+	goCmd(t, "install", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "./depBase")
+
+	// Run 'go list' after 'go install': with gccgo, we apparently don't know the
+	// shlib location until after we've installed it.
+	shlib := goCmd(t, "list", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "-f", "{{.Shlib}}", "./depBase")
+
+	AssertIsLinkedToRegexp(t, shlib, libgoRE)
+	goCmd(t, "install", "-compiler=gccgo", "-linkshared", "./exe")
+	AssertIsLinkedToRegexp(t, "../../bin/exe", libgoRE)
+	AssertIsLinkedTo(t, "../../bin/exe", filepath.Base(shlib))
+	AssertHasRPath(t, "../../bin/exe", filepath.Dir(shlib))
 	// And check it runs.
-	run(t, "gccgo-built", "./bin/exe")
+	run(t, "gccgo-built", "../../bin/exe")
 }
 
 // The gccgo version of TestTwoGopathShlibs: build a GOPATH package into a shared
 // library with gccgo, another GOPATH package that depends on the first and an
 // executable that links the second library.
 func TestTwoGopathShlibsGccgo(t *testing.T) {
-	gccgoContext := prepGccgo(t)
+	requireGccgo(t)
 
 	libgoRE := regexp.MustCompile("libgo.so.[0-9]+")
 
-	depP, err := gccgoContext.Import("depBase", ".", build.ImportComment)
-	if err != nil {
-		t.Fatalf("import failed: %v", err)
-	}
-	gccgoInstallDir := filepath.Join(depP.PkgTargetRoot, "shlibs")
-	goCmd(t, "install", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "depBase")
-	goCmd(t, "install", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "dep2")
-	goCmd(t, "install", "-compiler=gccgo", "-linkshared", "exe2")
+	goCmd(t, "install", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "./depBase")
+	goCmd(t, "install", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "./dep2")
+	goCmd(t, "install", "-compiler=gccgo", "-linkshared", "./exe2")
+
+	// Run 'go list' after 'go install': with gccgo, we apparently don't know the
+	// shlib location until after we've installed it.
+	dep2 := goCmd(t, "list", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "-f", "{{.Shlib}}", "./dep2")
+	depBase := goCmd(t, "list", "-compiler=gccgo", "-buildmode=shared", "-linkshared", "-f", "{{.Shlib}}", "./depBase")
 
-	AssertIsLinkedToRegexp(t, filepath.Join(gccgoInstallDir, "libdepBase.so"), libgoRE)
-	AssertIsLinkedToRegexp(t, filepath.Join(gccgoInstallDir, "libdep2.so"), libgoRE)
-	AssertIsLinkedTo(t, filepath.Join(gccgoInstallDir, "libdep2.so"), "libdepBase.so")
-	AssertIsLinkedToRegexp(t, "./bin/exe2", libgoRE)
-	AssertIsLinkedTo(t, "./bin/exe2", "libdep2")
-	AssertIsLinkedTo(t, "./bin/exe2", "libdepBase.so")
+	AssertIsLinkedToRegexp(t, depBase, libgoRE)
+	AssertIsLinkedToRegexp(t, dep2, libgoRE)
+	AssertIsLinkedTo(t, dep2, filepath.Base(depBase))
+	AssertIsLinkedToRegexp(t, "../../bin/exe2", libgoRE)
+	AssertIsLinkedTo(t, "../../bin/exe2", filepath.Base(dep2))
+	AssertIsLinkedTo(t, "../../bin/exe2", filepath.Base(depBase))
 
 	// And check it runs.
-	run(t, "gccgo-built", "./bin/exe2")
+	run(t, "gccgo-built", "../../bin/exe2")
 }
 
 // Testing rebuilding of shared libraries when they are stale is a bit more
@@ -694,9 +699,9 @@ func resetFileStamps() {
 		}
 
 	}
-	reset("bin")
-	reset("pkg")
-	reset("src")
+	reset("../../bin")
+	reset("../../pkg")
+	reset("../../src")
 	reset(gorootInstallDir)
 }
 
@@ -746,6 +751,7 @@ func touch(t *testing.T, path string) (cleanup func()) {
 
 // isNew returns if the path is newer than the time stamp used by touch.
 func isNew(t *testing.T, path string) bool {
+	t.Helper()
 	fi, err := os.Stat(path)
 	if err != nil {
 		t.Fatal(err)
@@ -771,40 +777,47 @@ func AssertNotRebuilt(t *testing.T, msg, path string) {
 }
 
 func TestRebuilding(t *testing.T) {
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
-	goCmd(t, "install", "-linkshared", "exe")
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./depBase")
+	goCmd(t, "install", "-linkshared", "./exe")
+	info := strings.Fields(goCmd(t, "list", "-buildmode=shared", "-linkshared", "-f", "{{.Target}} {{.Shlib}}", "./depBase"))
+	if len(info) != 2 {
+		t.Fatalf("go list failed to report Target and/or Shlib")
+	}
+	target := info[0]
+	shlib := info[1]
 
 	// If the source is newer than both the .a file and the .so, both are rebuilt.
 	t.Run("newsource", func(t *testing.T) {
 		resetFileStamps()
-		cleanup := touch(t, "src/depBase/dep.go")
+		cleanup := touch(t, "./depBase/dep.go")
 		defer func() {
 			cleanup()
-			goCmd(t, "install", "-linkshared", "exe")
+			goCmd(t, "install", "-linkshared", "./exe")
 		}()
-		goCmd(t, "install", "-linkshared", "exe")
-		AssertRebuilt(t, "new source", filepath.Join(gopathInstallDir, "depBase.a"))
-		AssertRebuilt(t, "new source", filepath.Join(gopathInstallDir, "libdepBase.so"))
+		goCmd(t, "install", "-linkshared", "./exe")
+		AssertRebuilt(t, "new source", target)
+		AssertRebuilt(t, "new source", shlib)
 	})
 
 	// If the .a file is newer than the .so, the .so is rebuilt (but not the .a)
 	t.Run("newarchive", func(t *testing.T) {
 		resetFileStamps()
-		AssertNotRebuilt(t, "new .a file before build", filepath.Join(gopathInstallDir, "depBase.a"))
-		goCmd(t, "list", "-linkshared", "-f={{.ImportPath}} {{.Stale}} {{.StaleReason}} {{.Target}}", "depBase")
-		AssertNotRebuilt(t, "new .a file before build", filepath.Join(gopathInstallDir, "depBase.a"))
-		cleanup := touch(t, filepath.Join(gopathInstallDir, "depBase.a"))
+		AssertNotRebuilt(t, "new .a file before build", target)
+		goCmd(t, "list", "-linkshared", "-f={{.ImportPath}} {{.Stale}} {{.StaleReason}} {{.Target}}", "./depBase")
+		AssertNotRebuilt(t, "new .a file before build", target)
+		cleanup := touch(t, target)
 		defer func() {
 			cleanup()
-			goCmd(t, "install", "-v", "-linkshared", "exe")
+			goCmd(t, "install", "-v", "-linkshared", "./exe")
 		}()
-		goCmd(t, "install", "-v", "-linkshared", "exe")
-		AssertNotRebuilt(t, "new .a file", filepath.Join(gopathInstallDir, "depBase.a"))
-		AssertRebuilt(t, "new .a file", filepath.Join(gopathInstallDir, "libdepBase.so"))
+		goCmd(t, "install", "-v", "-linkshared", "./exe")
+		AssertNotRebuilt(t, "new .a file", target)
+		AssertRebuilt(t, "new .a file", shlib)
 	})
 }
 
 func appendFile(t *testing.T, path, content string) {
+	t.Helper()
 	f, err := os.OpenFile(path, os.O_WRONLY|os.O_APPEND, 0660)
 	if err != nil {
 		t.Fatalf("os.OpenFile failed: %v", err)
@@ -821,16 +834,24 @@ func appendFile(t *testing.T, path, content string) {
 	}
 }
 
-func writeFile(t *testing.T, path, content string) {
-	err := ioutil.WriteFile(path, []byte(content), 0644)
+func createFile(t *testing.T, path, content string) {
+	t.Helper()
+	f, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE|os.O_EXCL, 0644)
 	if err != nil {
-		t.Fatalf("ioutil.WriteFile failed: %v", err)
+		t.Fatalf("os.OpenFile failed: %v", err)
+	}
+	_, err = f.WriteString(content)
+	if closeErr := f.Close(); err == nil {
+		err = closeErr
+	}
+	if err != nil {
+		t.Fatalf("WriteString failed: %v", err)
 	}
 }
 
 func TestABIChecking(t *testing.T) {
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
-	goCmd(t, "install", "-linkshared", "exe")
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./depBase")
+	goCmd(t, "install", "-linkshared", "./exe")
 
 	// If we make an ABI-breaking change to depBase and rebuild libp.so but not exe,
 	// exe will abort with a complaint on startup.
@@ -838,18 +859,21 @@ func TestABIChecking(t *testing.T) {
 	// some senses but suffices for the narrow definition of ABI compatibility the
 	// toolchain uses today.
 	resetFileStamps()
-	appendFile(t, "src/depBase/dep.go", "func ABIBreak() {}\n")
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
-	c := exec.Command("./bin/exe")
+
+	createFile(t, "./depBase/break.go", "package depBase\nfunc ABIBreak() {}\n")
+	defer os.Remove("./depBase/break.go")
+
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./depBase")
+	c := exec.Command("../../bin/exe")
 	output, err := c.CombinedOutput()
 	if err == nil {
 		t.Fatal("executing exe did not fail after ABI break")
 	}
 	scanner := bufio.NewScanner(bytes.NewReader(output))
 	foundMsg := false
-	const wantLine = "abi mismatch detected between the executable and libdepBase.so"
+	const wantPrefix = "abi mismatch detected between the executable and lib"
 	for scanner.Scan() {
-		if scanner.Text() == wantLine {
+		if strings.HasPrefix(scanner.Text(), wantPrefix) {
 			foundMsg = true
 			break
 		}
@@ -858,20 +882,20 @@ func TestABIChecking(t *testing.T) {
 		t.Errorf("scanner encountered error: %v", err)
 	}
 	if !foundMsg {
-		t.Fatalf("exe failed, but without line %q; got output:\n%s", wantLine, output)
+		t.Fatalf("exe failed, but without line %q; got output:\n%s", wantPrefix, output)
 	}
 
 	// Rebuilding exe makes it work again.
-	goCmd(t, "install", "-linkshared", "exe")
-	run(t, "rebuilt exe", "./bin/exe")
+	goCmd(t, "install", "-linkshared", "./exe")
+	run(t, "rebuilt exe", "../../bin/exe")
 
 	// If we make a change which does not break ABI (such as adding an unexported
 	// function) and rebuild libdepBase.so, exe still works, even if new function
 	// is in a file by itself.
 	resetFileStamps()
-	writeFile(t, "src/depBase/dep2.go", "package depBase\nfunc noABIBreak() {}\n")
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "depBase")
-	run(t, "after non-ABI breaking change", "./bin/exe")
+	createFile(t, "./depBase/dep2.go", "package depBase\nfunc noABIBreak() {}\n")
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./depBase")
+	run(t, "after non-ABI breaking change", "../../bin/exe")
 }
 
 // If a package 'explicit' imports a package 'implicit', building
@@ -881,29 +905,29 @@ func TestABIChecking(t *testing.T) {
 // executable rather than fetching it from the shared library. The
 // link still succeeds and the executable still runs though.
 func TestImplicitInclusion(t *testing.T) {
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "explicit")
-	goCmd(t, "install", "-linkshared", "implicitcmd")
-	run(t, "running executable linked against library that contains same package as it", "./bin/implicitcmd")
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./explicit")
+	goCmd(t, "install", "-linkshared", "./implicitcmd")
+	run(t, "running executable linked against library that contains same package as it", "../../bin/implicitcmd")
 }
 
 // Tests to make sure that the type fields of empty interfaces and itab
 // fields of nonempty interfaces are unique even across modules,
 // so that interface equality works correctly.
 func TestInterface(t *testing.T) {
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "iface_a")
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./iface_a")
 	// Note: iface_i gets installed implicitly as a dependency of iface_a.
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "iface_b")
-	goCmd(t, "install", "-linkshared", "iface")
-	run(t, "running type/itab uniqueness tester", "./bin/iface")
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./iface_b")
+	goCmd(t, "install", "-linkshared", "./iface")
+	run(t, "running type/itab uniqueness tester", "../../bin/iface")
 }
 
 // Access a global variable from a library.
 func TestGlobal(t *testing.T) {
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "globallib")
-	goCmd(t, "install", "-linkshared", "global")
-	run(t, "global executable", "./bin/global")
-	AssertIsLinkedTo(t, "./bin/global", soname)
-	AssertHasRPath(t, "./bin/global", gorootInstallDir)
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./globallib")
+	goCmd(t, "install", "-linkshared", "./global")
+	run(t, "global executable", "../../bin/global")
+	AssertIsLinkedTo(t, "../../bin/global", soname)
+	AssertHasRPath(t, "../../bin/global", gorootInstallDir)
 }
 
 // Run a test using -linkshared of an installed shared package.
@@ -915,5 +939,5 @@ func TestTestInstalledShared(t *testing.T) {
 // Test generated pointer method with -linkshared.
 // Issue 25065.
 func TestGeneratedMethod(t *testing.T) {
-	goCmd(t, "install", "-buildmode=shared", "-linkshared", "issue25065")
+	goCmd(t, "install", "-buildmode=shared", "-linkshared", "./issue25065")
 }
diff --git a/libgo/misc/cgo/testshared/src/dep2/dep2.go b/libgo/misc/cgo/testshared/testdata/dep2/dep2.go
index c2c812adb9b..94f38cf507f 100644
--- a/libgo/misc/cgo/testshared/src/dep2/dep2.go
+++ b/libgo/misc/cgo/testshared/testdata/dep2/dep2.go
@@ -1,6 +1,6 @@
 package dep2
 
-import "depBase"
+import "testshared/depBase"
 
 var W int = 1
 
diff --git a/libgo/misc/cgo/testshared/src/dep3/dep3.go b/libgo/misc/cgo/testshared/testdata/dep3/dep3.go
index 7b7c9dac1f9..6b02ad2ee5b 100644
--- a/libgo/misc/cgo/testshared/src/dep3/dep3.go
+++ b/libgo/misc/cgo/testshared/testdata/dep3/dep3.go
@@ -7,8 +7,8 @@ package dep3
 // the type data in this case and later crash.
 
 import (
-	"dep2"
-	"depBase"
+	"testshared/dep2"
+	"testshared/depBase"
 )
 
 type Dep3 struct {
diff --git a/libgo/misc/cgo/testshared/src/depBase/asm.s b/libgo/misc/cgo/testshared/testdata/depBase/asm.s
index a8acf77f0b9..a8acf77f0b9 100644
--- a/libgo/misc/cgo/testshared/src/depBase/asm.s
+++ b/libgo/misc/cgo/testshared/testdata/depBase/asm.s
diff --git a/libgo/misc/cgo/testshared/src/depBase/dep.go b/libgo/misc/cgo/testshared/testdata/depBase/dep.go
index e7cc7c81eb3..e7cc7c81eb3 100644
--- a/libgo/misc/cgo/testshared/src/depBase/dep.go
+++ b/libgo/misc/cgo/testshared/testdata/depBase/dep.go
diff --git a/libgo/misc/cgo/testshared/src/depBase/gccgo.go b/libgo/misc/cgo/testshared/testdata/depBase/gccgo.go
index 2b02a1e83b7..2b02a1e83b7 100644
--- a/libgo/misc/cgo/testshared/src/depBase/gccgo.go
+++ b/libgo/misc/cgo/testshared/testdata/depBase/gccgo.go
diff --git a/libgo/misc/cgo/testshared/src/depBase/stubs.go b/libgo/misc/cgo/testshared/testdata/depBase/stubs.go
index 04534f38ddd..04534f38ddd 100644
--- a/libgo/misc/cgo/testshared/src/depBase/stubs.go
+++ b/libgo/misc/cgo/testshared/testdata/depBase/stubs.go
diff --git a/libgo/misc/cgo/testshared/src/division/division.go b/libgo/misc/cgo/testshared/testdata/division/division.go
index bb5fc984602..bb5fc984602 100644
--- a/libgo/misc/cgo/testshared/src/division/division.go
+++ b/libgo/misc/cgo/testshared/testdata/division/division.go
diff --git a/libgo/misc/cgo/testshared/src/exe/exe.go b/libgo/misc/cgo/testshared/testdata/exe/exe.go
index bd864d88ad8..ee95f97bc99 100644
--- a/libgo/misc/cgo/testshared/src/exe/exe.go
+++ b/libgo/misc/cgo/testshared/testdata/exe/exe.go
@@ -1,10 +1,11 @@
 package main
 
 import (
-	"depBase"
 	"os"
 	"reflect"
 	"runtime"
+
+	"testshared/depBase"
 )
 
 // Having a function declared in the main package triggered
diff --git a/libgo/misc/cgo/testshared/src/exe2/exe2.go b/libgo/misc/cgo/testshared/testdata/exe2/exe2.go
index 675fd1f365c..433f331e369 100644
--- a/libgo/misc/cgo/testshared/src/exe2/exe2.go
+++ b/libgo/misc/cgo/testshared/testdata/exe2/exe2.go
@@ -1,6 +1,6 @@
 package main
 
-import "dep2"
+import "testshared/dep2"
 
 func main() {
 	d := &dep2.Dep2{}
diff --git a/libgo/misc/cgo/testshared/src/exe3/exe3.go b/libgo/misc/cgo/testshared/testdata/exe3/exe3.go
index 643f2605f66..533e3a9e3dd 100644
--- a/libgo/misc/cgo/testshared/src/exe3/exe3.go
+++ b/libgo/misc/cgo/testshared/testdata/exe3/exe3.go
@@ -1,6 +1,6 @@
 package main
 
-import "dep3"
+import "testshared/dep3"
 
 func main() {
 	dep3.D3()
diff --git a/libgo/misc/cgo/testshared/src/execgo/exe.go b/libgo/misc/cgo/testshared/testdata/execgo/exe.go
index 0427be8bdfd..0427be8bdfd 100644
--- a/libgo/misc/cgo/testshared/src/execgo/exe.go
+++ b/libgo/misc/cgo/testshared/testdata/execgo/exe.go
diff --git a/libgo/misc/cgo/testshared/src/explicit/explicit.go b/libgo/misc/cgo/testshared/testdata/explicit/explicit.go
index 6a4453f7758..af969fcb23a 100644
--- a/libgo/misc/cgo/testshared/src/explicit/explicit.go
+++ b/libgo/misc/cgo/testshared/testdata/explicit/explicit.go
@@ -1,7 +1,7 @@
 package explicit
 
 import (
-	"implicit"
+	"testshared/implicit"
 )
 
 func E() int {
diff --git a/libgo/misc/cgo/testshared/src/global/main.go b/libgo/misc/cgo/testshared/testdata/global/main.go
index 94e7f247dee..f43e7c3fb35 100644
--- a/libgo/misc/cgo/testshared/src/global/main.go
+++ b/libgo/misc/cgo/testshared/testdata/global/main.go
@@ -5,7 +5,7 @@
 package main
 
 import (
-	"globallib"
+	"testshared/globallib"
 )
 
 //go:noinline
diff --git a/libgo/misc/cgo/testshared/src/globallib/global.go b/libgo/misc/cgo/testshared/testdata/globallib/global.go
index b4372a2e9e2..b4372a2e9e2 100644
--- a/libgo/misc/cgo/testshared/src/globallib/global.go
+++ b/libgo/misc/cgo/testshared/testdata/globallib/global.go
diff --git a/libgo/misc/cgo/testshared/src/iface/main.go b/libgo/misc/cgo/testshared/testdata/iface/main.go
index 3d5b54e73b9..d26ebbcc9cc 100644
--- a/libgo/misc/cgo/testshared/src/iface/main.go
+++ b/libgo/misc/cgo/testshared/testdata/iface/main.go
@@ -4,8 +4,8 @@
 
 package main
 
-import "iface_a"
-import "iface_b"
+import "testshared/iface_a"
+import "testshared/iface_b"
 
 func main() {
 	if iface_a.F() != iface_b.F() {
diff --git a/libgo/misc/cgo/testshared/src/iface_a/a.go b/libgo/misc/cgo/testshared/testdata/iface_a/a.go
index e11047c166c..e2cef1ecda6 100644
--- a/libgo/misc/cgo/testshared/src/iface_a/a.go
+++ b/libgo/misc/cgo/testshared/testdata/iface_a/a.go
@@ -4,7 +4,7 @@
 
 package iface_a
 
-import "iface_i"
+import "testshared/iface_i"
 
 //go:noinline
 func F() interface{} {
diff --git a/libgo/misc/cgo/testshared/src/iface_b/b.go b/libgo/misc/cgo/testshared/testdata/iface_b/b.go
index 47aee2e77ee..dd3e027b37a 100644
--- a/libgo/misc/cgo/testshared/src/iface_b/b.go
+++ b/libgo/misc/cgo/testshared/testdata/iface_b/b.go
@@ -4,7 +4,7 @@
 
 package iface_b
 
-import "iface_i"
+import "testshared/iface_i"
 
 //go:noinline
 func F() interface{} {
diff --git a/libgo/misc/cgo/testshared/src/iface_i/i.go b/libgo/misc/cgo/testshared/testdata/iface_i/i.go
index 31c80387c7e..31c80387c7e 100644
--- a/libgo/misc/cgo/testshared/src/iface_i/i.go
+++ b/libgo/misc/cgo/testshared/testdata/iface_i/i.go
diff --git a/libgo/misc/cgo/testshared/src/implicit/implicit.go b/libgo/misc/cgo/testshared/testdata/implicit/implicit.go
index 5360188c562..5360188c562 100644
--- a/libgo/misc/cgo/testshared/src/implicit/implicit.go
+++ b/libgo/misc/cgo/testshared/testdata/implicit/implicit.go
diff --git a/libgo/misc/cgo/testshared/src/implicitcmd/implicitcmd.go b/libgo/misc/cgo/testshared/testdata/implicitcmd/implicitcmd.go
index f6112933e56..4d4296738e3 100644
--- a/libgo/misc/cgo/testshared/src/implicitcmd/implicitcmd.go
+++ b/libgo/misc/cgo/testshared/testdata/implicitcmd/implicitcmd.go
@@ -1,8 +1,8 @@
 package main
 
 import (
-	"explicit"
-	"implicit"
+	"testshared/explicit"
+	"testshared/implicit"
 )
 
 func main() {
diff --git a/libgo/misc/cgo/testshared/src/issue25065/a.go b/libgo/misc/cgo/testshared/testdata/issue25065/a.go
index 979350ff24c..979350ff24c 100644
--- a/libgo/misc/cgo/testshared/src/issue25065/a.go
+++ b/libgo/misc/cgo/testshared/testdata/issue25065/a.go
diff --git a/libgo/misc/cgo/testshared/src/trivial/trivial.go b/libgo/misc/cgo/testshared/testdata/trivial/trivial.go
index 6ade47ce36f..6ade47ce36f 100644
--- a/libgo/misc/cgo/testshared/src/trivial/trivial.go
+++ b/libgo/misc/cgo/testshared/testdata/trivial/trivial.go
diff --git a/libgo/misc/cgo/testso/noso_test.go b/libgo/misc/cgo/testso/noso_test.go
new file mode 100644
index 00000000000..c88aebfb02a
--- /dev/null
+++ b/libgo/misc/cgo/testso/noso_test.go
@@ -0,0 +1,9 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !cgo
+
+package so_test
+
+// Nothing to test.
diff --git a/libgo/misc/cgo/testso/overlaydir_test.go b/libgo/misc/cgo/testso/overlaydir_test.go
new file mode 100644
index 00000000000..10c874d9258
--- /dev/null
+++ b/libgo/misc/cgo/testso/overlaydir_test.go
@@ -0,0 +1,81 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package so_test
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// overlayDir makes a minimal-overhead copy of srcRoot in which new files may be added.
+//
+// TODO: Once we no longer need to support the misc module in GOPATH mode,
+// factor this function out into a package to reduce duplication.
+func overlayDir(dstRoot, srcRoot string) error {
+	dstRoot = filepath.Clean(dstRoot)
+	if err := os.MkdirAll(dstRoot, 0777); err != nil {
+		return err
+	}
+
+	symBase, err := filepath.Rel(srcRoot, dstRoot)
+	if err != nil {
+		symBase, err = filepath.Abs(srcRoot)
+		if err != nil {
+			return err
+		}
+	}
+
+	return filepath.Walk(srcRoot, func(srcPath string, info os.FileInfo, err error) error {
+		if err != nil || srcPath == srcRoot {
+			return err
+		}
+
+		suffix := strings.TrimPrefix(srcPath, srcRoot)
+		for len(suffix) > 0 && suffix[0] == filepath.Separator {
+			suffix = suffix[1:]
+		}
+		dstPath := filepath.Join(dstRoot, suffix)
+
+		perm := info.Mode() & os.ModePerm
+		if info.Mode()&os.ModeSymlink != 0 {
+			info, err = os.Stat(srcPath)
+			if err != nil {
+				return err
+			}
+			perm = info.Mode() & os.ModePerm
+		}
+
+		// Always copy directories (don't symlink them).
+		// If we add a file in the overlay, we don't want to add it in the original.
+		if info.IsDir() {
+			return os.Mkdir(dstPath, perm)
+		}
+
+		// If the OS supports symlinks, use them instead of copying bytes.
+		if err := os.Symlink(filepath.Join(symBase, suffix), dstPath); err == nil {
+			return nil
+		}
+
+		// Otherwise, copy the bytes.
+		src, err := os.Open(srcPath)
+		if err != nil {
+			return err
+		}
+		defer src.Close()
+
+		dst, err := os.OpenFile(dstPath, os.O_WRONLY|os.O_CREATE|os.O_EXCL, perm)
+		if err != nil {
+			return err
+		}
+
+		_, err = io.Copy(dst, src)
+		if closeErr := dst.Close(); err == nil {
+			err = closeErr
+		}
+		return err
+	})
+}
diff --git a/libgo/misc/cgo/testso/so_test.go b/libgo/misc/cgo/testso/so_test.go
new file mode 100644
index 00000000000..9c7f2724390
--- /dev/null
+++ b/libgo/misc/cgo/testso/so_test.go
@@ -0,0 +1,140 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build cgo
+
+package so_test
+
+import (
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+)
+
+func requireTestSOSupported(t *testing.T) {
+	t.Helper()
+	switch runtime.GOARCH {
+	case "arm", "arm64":
+		if runtime.GOOS == "darwin" {
+			t.Skip("No exec facility on iOS.")
+		}
+	case "ppc64":
+		if runtime.GOOS == "linux" {
+			t.Skip("External linking not implemented on aix/ppc64 (issue #8912).")
+		}
+	case "mips64le", "mips64":
+		t.Skip("External linking not implemented on mips64.")
+	}
+	if runtime.GOOS == "android" {
+		t.Skip("No exec facility on Android.")
+	}
+}
+
+func TestSO(t *testing.T) {
+	requireTestSOSupported(t)
+
+	GOPATH, err := ioutil.TempDir("", "cgosotest")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer os.RemoveAll(GOPATH)
+
+	modRoot := filepath.Join(GOPATH, "src", "cgosotest")
+	if err := overlayDir(modRoot, "testdata"); err != nil {
+		log.Panic(err)
+	}
+	if err := ioutil.WriteFile(filepath.Join(modRoot, "go.mod"), []byte("module cgosotest\n"), 0666); err != nil {
+		log.Panic(err)
+	}
+
+	cmd := exec.Command("go", "env", "CC", "GOGCCFLAGS")
+	cmd.Dir = modRoot
+	cmd.Stderr = new(strings.Builder)
+	cmd.Env = append(os.Environ(), "GOPATH="+GOPATH)
+	out, err := cmd.Output()
+	if err != nil {
+		t.Fatalf("%s: %v\n%s", strings.Join(cmd.Args, " "), err, cmd.Stderr)
+	}
+	lines := strings.Split(string(out), "\n")
+	if len(lines) != 3 || lines[2] != "" {
+		t.Fatalf("Unexpected output from %s:\n%s", strings.Join(cmd.Args, " "), lines)
+	}
+
+	cc := lines[0]
+	if cc == "" {
+		t.Fatal("CC environment variable (go env CC) cannot be empty")
+	}
+	gogccflags := strings.Split(lines[1], " ")
+
+	// build shared object
+	ext := "so"
+	args := append(gogccflags, "-shared")
+	switch runtime.GOOS {
+	case "darwin":
+		ext = "dylib"
+		args = append(args, "-undefined", "suppress", "-flat_namespace")
+	case "windows":
+		ext = "dll"
+		args = append(args, "-DEXPORT_DLL")
+	case "aix":
+		ext = "so.1"
+	}
+	sofname := "libcgosotest." + ext
+	args = append(args, "-o", sofname, "cgoso_c.c")
+
+	cmd = exec.Command(cc, args...)
+	cmd.Dir = modRoot
+	cmd.Env = append(os.Environ(), "GOPATH="+GOPATH)
+	out, err = cmd.CombinedOutput()
+	if err != nil {
+		t.Fatalf("%s: %s\n%s", strings.Join(cmd.Args, " "), err, out)
+	}
+	t.Logf("%s:\n%s", strings.Join(cmd.Args, " "), out)
+
+	if runtime.GOOS == "aix" {
+		// Shared object must be wrapped by an archive
+		cmd = exec.Command("ar", "-X64", "-q", "libcgosotest.a", "libcgosotest.so.1")
+		cmd.Dir = modRoot
+		out, err = cmd.CombinedOutput()
+		if err != nil {
+			t.Fatalf("%s: %s\n%s", strings.Join(cmd.Args, " "), err, out)
+		}
+	}
+
+	cmd = exec.Command("go", "build", "-o", "main.exe", "main.go")
+	cmd.Dir = modRoot
+	cmd.Env = append(os.Environ(), "GOPATH="+GOPATH)
+	out, err = cmd.CombinedOutput()
+	if err != nil {
+		t.Fatalf("%s: %s\n%s", strings.Join(cmd.Args, " "), err, out)
+	}
+	t.Logf("%s:\n%s", strings.Join(cmd.Args, " "), out)
+
+	cmd = exec.Command("./main.exe")
+	cmd.Dir = modRoot
+	cmd.Env = append(os.Environ(), "GOPATH="+GOPATH)
+	if runtime.GOOS != "windows" {
+		s := "LD_LIBRARY_PATH"
+		if runtime.GOOS == "darwin" {
+			s = "DYLD_LIBRARY_PATH"
+		}
+		cmd.Env = append(os.Environ(), s+"=.")
+
+		// On FreeBSD 64-bit architectures, the 32-bit linker looks for
+		// different environment variables.
+		if runtime.GOOS == "freebsd" && runtime.GOARCH == "386" {
+			cmd.Env = append(cmd.Env, "LD_32_LIBRARY_PATH=.")
+		}
+	}
+	out, err = cmd.CombinedOutput()
+	if err != nil {
+		t.Fatalf("%s: %s\n%s", strings.Join(cmd.Args, " "), err, out)
+	}
+	t.Logf("%s:\n%s", strings.Join(cmd.Args, " "), out)
+}
diff --git a/libgo/misc/cgo/testso/cgoso.c b/libgo/misc/cgo/testso/testdata/cgoso.c
index 917f472d368..612e5d335a9 100644
--- a/libgo/misc/cgo/testso/cgoso.c
+++ b/libgo/misc/cgo/testso/testdata/cgoso.c
@@ -4,7 +4,7 @@
 
 #include "_cgo_export.h"
 
-#ifdef WIN32
+#if defined(WIN32) || defined(_AIX)
 extern void setCallback(void *);
 void init() {
 	setCallback(goCallback);
diff --git a/libgo/misc/cgo/testso/cgoso.go b/libgo/misc/cgo/testso/testdata/cgoso.go
index 29814fa43ae..bba5de33121 100644
--- a/libgo/misc/cgo/testso/cgoso.go
+++ b/libgo/misc/cgo/testso/testdata/cgoso.go
@@ -15,6 +15,7 @@ package cgosotest
 #cgo netbsd LDFLAGS: -L. libcgosotest.so
 #cgo darwin LDFLAGS: -L. libcgosotest.dylib
 #cgo windows LDFLAGS: -L. libcgosotest.dll
+#cgo aix LDFLAGS: -L. -l cgosotest
 
 void init(void);
 void sofunc(void);
diff --git a/libgo/misc/cgo/testso/cgoso_c.c b/libgo/misc/cgo/testso/testdata/cgoso_c.c
index 7a38022b547..e5015ed5e8c 100644
--- a/libgo/misc/cgo/testso/cgoso_c.c
+++ b/libgo/misc/cgo/testso/testdata/cgoso_c.c
@@ -14,6 +14,15 @@ __declspec(dllexport) void setCallback(void *f)
 	goCallback = (void (*)())f;
 }
 __declspec(dllexport) void sofunc(void);
+#elif defined(_AIX)
+// AIX doesn't allow the creation of a shared object with an
+// undefined symbol. It's possible to bypass this problem by
+// using -Wl,-G and -Wl,-brtl option which allows run-time linking.
+// However, that's not how most of AIX shared object works.
+// Therefore, it's better to consider goCallback as a pointer and
+// to set up during an init function.
+void (*goCallback)(void);
+void setCallback(void *f) { goCallback = f; }
 #else
 extern void goCallback(void);
 void setCallback(void *f) { (void)f; }
diff --git a/libgo/misc/cgo/testso/cgoso_unix.go b/libgo/misc/cgo/testso/testdata/cgoso_unix.go
index 49cdeaa2f59..1860694f1ed 100644
--- a/libgo/misc/cgo/testso/cgoso_unix.go
+++ b/libgo/misc/cgo/testso/testdata/cgoso_unix.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build dragonfly freebsd linux netbsd solaris
+// +build aix dragonfly freebsd linux netbsd solaris
 
 package cgosotest
 
diff --git a/libgo/misc/cgo/testso/main.go b/libgo/misc/cgo/testso/testdata/main.go
index 88aa4322d24..963d45121e4 100644
--- a/libgo/misc/cgo/testso/main.go
+++ b/libgo/misc/cgo/testso/testdata/main.go
@@ -6,7 +6,7 @@
 
 package main
 
-import "."
+import "cgosotest"
 
 func main() {
 	cgosotest.Test()
diff --git a/libgo/misc/cgo/testsovar/noso_test.go b/libgo/misc/cgo/testsovar/noso_test.go
new file mode 100644
index 00000000000..c88aebfb02a
--- /dev/null
+++ b/libgo/misc/cgo/testsovar/noso_test.go
@@ -0,0 +1,9 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !cgo
+
+package so_test
+
+// Nothing to test.
diff --git a/libgo/misc/cgo/testsovar/overlaydir_test.go b/libgo/misc/cgo/testsovar/overlaydir_test.go
new file mode 100644
index 00000000000..10c874d9258
--- /dev/null
+++ b/libgo/misc/cgo/testsovar/overlaydir_test.go
@@ -0,0 +1,81 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package so_test
+
+import (
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// overlayDir makes a minimal-overhead copy of srcRoot in which new files may be added.
+//
+// TODO: Once we no longer need to support the misc module in GOPATH mode,
+// factor this function out into a package to reduce duplication.
+func overlayDir(dstRoot, srcRoot string) error {
+	dstRoot = filepath.Clean(dstRoot)
+	if err := os.MkdirAll(dstRoot, 0777); err != nil {
+		return err
+	}
+
+	symBase, err := filepath.Rel(srcRoot, dstRoot)
+	if err != nil {
+		symBase, err = filepath.Abs(srcRoot)
+		if err != nil {
+			return err
+		}
+	}
+
+	return filepath.Walk(srcRoot, func(srcPath string, info os.FileInfo, err error) error {
+		if err != nil || srcPath == srcRoot {
+			return err
+		}
+
+		suffix := strings.TrimPrefix(srcPath, srcRoot)
+		for len(suffix) > 0 && suffix[0] == filepath.Separator {
+			suffix = suffix[1:]
+		}
+		dstPath := filepath.Join(dstRoot, suffix)
+
+		perm := info.Mode() & os.ModePerm
+		if info.Mode()&os.ModeSymlink != 0 {
+			info, err = os.Stat(srcPath)
+			if err != nil {
+				return err
+			}
+			perm = info.Mode() & os.ModePerm
+		}
+
+		// Always copy directories (don't symlink them).
+		// If we add a file in the overlay, we don't want to add it in the original.
+		if info.IsDir() {
+			return os.Mkdir(dstPath, perm)
+		}
+
+		// If the OS supports symlinks, use them instead of copying bytes.
+		if err := os.Symlink(filepath.Join(symBase, suffix), dstPath); err == nil {
+			return nil
+		}
+
+		// Otherwise, copy the bytes.
+		src, err := os.Open(srcPath)
+		if err != nil {
+			return err
+		}
+		defer src.Close()
+
+		dst, err := os.OpenFile(dstPath, os.O_WRONLY|os.O_CREATE|os.O_EXCL, perm)
+		if err != nil {
+			return err
+		}
+
+		_, err = io.Copy(dst, src)
+		if closeErr := dst.Close(); err == nil {
+			err = closeErr
+		}
+		return err
+	})
+}
diff --git a/libgo/misc/cgo/testsovar/so_test.go b/libgo/misc/cgo/testsovar/so_test.go
new file mode 100644
index 00000000000..9c7f2724390
--- /dev/null
+++ b/libgo/misc/cgo/testsovar/so_test.go
@@ -0,0 +1,140 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build cgo
+
+package so_test
+
+import (
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+)
+
+func requireTestSOSupported(t *testing.T) {
+	t.Helper()
+	switch runtime.GOARCH {
+	case "arm", "arm64":
+		if runtime.GOOS == "darwin" {
+			t.Skip("No exec facility on iOS.")
+		}
+	case "ppc64":
+		if runtime.GOOS == "linux" {
+			t.Skip("External linking not implemented on aix/ppc64 (issue #8912).")
+		}
+	case "mips64le", "mips64":
+		t.Skip("External linking not implemented on mips64.")
+	}
+	if runtime.GOOS == "android" {
+		t.Skip("No exec facility on Android.")
+	}
+}
+
+func TestSO(t *testing.T) {
+	requireTestSOSupported(t)
+
+	GOPATH, err := ioutil.TempDir("", "cgosotest")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer os.RemoveAll(GOPATH)
+
+	modRoot := filepath.Join(GOPATH, "src", "cgosotest")
+	if err := overlayDir(modRoot, "testdata"); err != nil {
+		log.Panic(err)
+	}
+	if err := ioutil.WriteFile(filepath.Join(modRoot, "go.mod"), []byte("module cgosotest\n"), 0666); err != nil {
+		log.Panic(err)
+	}
+
+	cmd := exec.Command("go", "env", "CC", "GOGCCFLAGS")
+	cmd.Dir = modRoot
+	cmd.Stderr = new(strings.Builder)
+	cmd.Env = append(os.Environ(), "GOPATH="+GOPATH)
+	out, err := cmd.Output()
+	if err != nil {
+		t.Fatalf("%s: %v\n%s", strings.Join(cmd.Args, " "), err, cmd.Stderr)
+	}
+	lines := strings.Split(string(out), "\n")
+	if len(lines) != 3 || lines[2] != "" {
+		t.Fatalf("Unexpected output from %s:\n%s", strings.Join(cmd.Args, " "), lines)
+	}
+
+	cc := lines[0]
+	if cc == "" {
+		t.Fatal("CC environment variable (go env CC) cannot be empty")
+	}
+	gogccflags := strings.Split(lines[1], " ")
+
+	// build shared object
+	ext := "so"
+	args := append(gogccflags, "-shared")
+	switch runtime.GOOS {
+	case "darwin":
+		ext = "dylib"
+		args = append(args, "-undefined", "suppress", "-flat_namespace")
+	case "windows":
+		ext = "dll"
+		args = append(args, "-DEXPORT_DLL")
+	case "aix":
+		ext = "so.1"
+	}
+	sofname := "libcgosotest." + ext
+	args = append(args, "-o", sofname, "cgoso_c.c")
+
+	cmd = exec.Command(cc, args...)
+	cmd.Dir = modRoot
+	cmd.Env = append(os.Environ(), "GOPATH="+GOPATH)
+	out, err = cmd.CombinedOutput()
+	if err != nil {
+		t.Fatalf("%s: %s\n%s", strings.Join(cmd.Args, " "), err, out)
+	}
+	t.Logf("%s:\n%s", strings.Join(cmd.Args, " "), out)
+
+	if runtime.GOOS == "aix" {
+		// Shared object must be wrapped by an archive
+		cmd = exec.Command("ar", "-X64", "-q", "libcgosotest.a", "libcgosotest.so.1")
+		cmd.Dir = modRoot
+		out, err = cmd.CombinedOutput()
+		if err != nil {
+			t.Fatalf("%s: %s\n%s", strings.Join(cmd.Args, " "), err, out)
+		}
+	}
+
+	cmd = exec.Command("go", "build", "-o", "main.exe", "main.go")
+	cmd.Dir = modRoot
+	cmd.Env = append(os.Environ(), "GOPATH="+GOPATH)
+	out, err = cmd.CombinedOutput()
+	if err != nil {
+		t.Fatalf("%s: %s\n%s", strings.Join(cmd.Args, " "), err, out)
+	}
+	t.Logf("%s:\n%s", strings.Join(cmd.Args, " "), out)
+
+	cmd = exec.Command("./main.exe")
+	cmd.Dir = modRoot
+	cmd.Env = append(os.Environ(), "GOPATH="+GOPATH)
+	if runtime.GOOS != "windows" {
+		s := "LD_LIBRARY_PATH"
+		if runtime.GOOS == "darwin" {
+			s = "DYLD_LIBRARY_PATH"
+		}
+		cmd.Env = append(os.Environ(), s+"=.")
+
+		// On FreeBSD 64-bit architectures, the 32-bit linker looks for
+		// different environment variables.
+		if runtime.GOOS == "freebsd" && runtime.GOARCH == "386" {
+			cmd.Env = append(cmd.Env, "LD_32_LIBRARY_PATH=.")
+		}
+	}
+	out, err = cmd.CombinedOutput()
+	if err != nil {
+		t.Fatalf("%s: %s\n%s", strings.Join(cmd.Args, " "), err, out)
+	}
+	t.Logf("%s:\n%s", strings.Join(cmd.Args, " "), out)
+}
diff --git a/libgo/misc/cgo/testsovar/cgoso.go b/libgo/misc/cgo/testsovar/testdata/cgoso.go
index 88d44c2c6ee..9c7f95e92ea 100644
--- a/libgo/misc/cgo/testsovar/cgoso.go
+++ b/libgo/misc/cgo/testsovar/testdata/cgoso.go
@@ -19,6 +19,7 @@ package cgosotest
 #cgo netbsd LDFLAGS: -L. libcgosotest.so
 #cgo darwin LDFLAGS: -L. libcgosotest.dylib
 #cgo windows LDFLAGS: -L. libcgosotest.dll
+#cgo aix LDFLAGS: -L. -l cgosotest
 
 #include "cgoso_c.h"
 
diff --git a/libgo/misc/cgo/testsovar/cgoso_c.c b/libgo/misc/cgo/testsovar/testdata/cgoso_c.c
index a448c013428..a448c013428 100644
--- a/libgo/misc/cgo/testsovar/cgoso_c.c
+++ b/libgo/misc/cgo/testsovar/testdata/cgoso_c.c
diff --git a/libgo/misc/cgo/testsovar/cgoso_c.h b/libgo/misc/cgo/testsovar/testdata/cgoso_c.h
index 640db7b396a..640db7b396a 100644
--- a/libgo/misc/cgo/testsovar/cgoso_c.h
+++ b/libgo/misc/cgo/testsovar/testdata/cgoso_c.h
diff --git a/libgo/misc/cgo/testsovar/main.go b/libgo/misc/cgo/testsovar/testdata/main.go
index 9c8a1c4e66e..87b52cef600 100644
--- a/libgo/misc/cgo/testsovar/main.go
+++ b/libgo/misc/cgo/testsovar/testdata/main.go
@@ -6,7 +6,7 @@
 
 package main
 
-import "."
+import "cgosotest"
 
 func main() {
 	cgosotest.Test()