cmd/gc: fix corruption in export of &T{} literals.

Composite literals using the &T{} form were incorrectly
exported, leading to weird errors at import time.

Fixes issue 4879.

R=golang-dev, rsc
CC=golang-dev
https://codereview.appspot.com/7395054

2 files changed, 42 insertions, 0 deletions

diff --git a/test/fixedbugs/issue4879.dir/a.go b/test/fixedbugs/issue4879.dir/a.go
new file mode 100644
index 000000000..7ee7c4860
--- /dev/null
+++ b/test/fixedbugs/issue4879.dir/a.go
@@ -0,0 +1,33 @@
+package a
+
+import (
+	"unsafe"
+)
+
+type Collection struct {
+	root unsafe.Pointer
+}
+
+type nodeLoc struct{}
+
+type slice []int
+
+type maptype map[int]int
+
+func MakePrivateCollection() *Collection {
+	return &Collection{
+		root: unsafe.Pointer(&nodeLoc{}),
+	}
+}
+
+func MakePrivateCollection2() *Collection {
+	return &Collection{
+		root: unsafe.Pointer(&slice{}),
+	}
+}
+func MakePrivateCollection3() *Collection {
+	return &Collection{
+		root: unsafe.Pointer(&maptype{}),
+	}
+}
+
diff --git a/test/fixedbugs/issue4879.dir/b.go b/test/fixedbugs/issue4879.dir/b.go
new file mode 100644
index 000000000..d8fb5693d
--- /dev/null
+++ b/test/fixedbugs/issue4879.dir/b.go
@@ -0,0 +1,9 @@
+package b
+
+import "./a"
+
+func F() {
+      a.MakePrivateCollection()
+      a.MakePrivateCollection2()
+      a.MakePrivateCollection3()
+}