Add a warning when we use in cdef() a global variable without also specifying a storage class (extern or static)

4 files changed, 48 insertions, 44 deletions

diff --git a/testing/cffi0/test_function.py b/testing/cffi0/test_function.py
index 120d7eb..d1f9ce4 100644
--- a/testing/cffi0/test_function.py
+++ b/testing/cffi0/test_function.py
@@ -113,7 +113,7 @@ class TestFunction(object):
         ffi = FFI(backend=self.Backend())
         ffi.cdef("""
             int fputs(const char *, void *);
-            void *stderr;
+            extern void *stderr;
         """)
         needs_dlopen_none()
         ffi.C = ffi.dlopen(None)
@@ -130,7 +130,7 @@ class TestFunction(object):
         ffi = FFI(backend=self.Backend())
         ffi.cdef("""
             int fputs(char *, void *);
-            void *stderr;
+            extern void *stderr;
         """)
         needs_dlopen_none()
         ffi.C = ffi.dlopen(None)
@@ -147,7 +147,7 @@ class TestFunction(object):
         ffi = FFI(backend=self.Backend())
         ffi.cdef("""
            int fprintf(void *, const char *format, ...);
-           void *stderr;
+           extern void *stderr;
         """)
         needs_dlopen_none()
         ffi.C = ffi.dlopen(None)
@@ -209,7 +209,7 @@ class TestFunction(object):
             py.test.skip("probably no symbol 'stderr' in the lib")
         ffi.cdef("""
             int fputs(const char *, void *);
-            void *stderr;
+            extern void *stderr;
         """)
         needs_dlopen_none()
         ffi.C = ffi.dlopen(None)
@@ -256,7 +256,7 @@ class TestFunction(object):
             py.test.skip("probably no symbol 'stdout' in the lib")
         ffi = FFI(backend=self.Backend())
         ffi.cdef("""
-            void *stdout;
+            extern void *stdout;
         """)
         needs_dlopen_none()
         C = ffi.dlopen(None)
@@ -496,7 +496,7 @@ class TestFunction(object):
         ffi.cdef("""
             typedef enum { MYE1, MYE2 } myenum_t;
             double myfunc(double);
-            double myvar;
+            extern double myvar;
             const double myconst;
             #define MYFOO 42
         """)
@@ -507,7 +507,7 @@ class TestFunction(object):
         if self.Backend is CTypesBackend:
             py.test.skip("not with the ctypes backend")
         ffi = FFI(backend=self.Backend())
-        ffi.cdef("int foobar(void); int foobaz;")
+        ffi.cdef("int foobar(void); extern int foobaz;")
         lib = ffi.dlopen(lib_m)
         ffi.dlclose(lib)
         e = py.test.raises(ValueError, getattr, lib, 'foobar')
diff --git a/testing/cffi0/test_ownlib.py b/testing/cffi0/test_ownlib.py
index a06df20..9295163 100644
--- a/testing/cffi0/test_ownlib.py
+++ b/testing/cffi0/test_ownlib.py
@@ -201,7 +201,7 @@ class TestOwnLib(object):
             py.test.skip("fix the auto-generation of the tiny test lib")
         ffi = FFI(backend=self.Backend())
         ffi.cdef("""
-            int my_array[7];
+            extern int my_array[7];
         """)
         ownlib = ffi.dlopen(self.module)
         for i in range(7):
@@ -223,7 +223,7 @@ class TestOwnLib(object):
             py.test.skip("not supported by the ctypes backend")
         ffi = FFI(backend=self.Backend())
         ffi.cdef("""
-            int my_array[];
+            extern int my_array[];
         """)
         ownlib = ffi.dlopen(self.module)
         for i in range(7):
@@ -291,7 +291,7 @@ class TestOwnLib(object):
                 long bottom;
             } RECT;
             
-            long left, top, right, bottom;
+            extern long left, top, right, bottom;
 
             RECT ReturnRect(int i, RECT ar, RECT* br, POINT cp, RECT dr,
                         RECT *er, POINT fp, RECT gr);
@@ -321,7 +321,7 @@ class TestOwnLib(object):
         if self.Backend is CTypesBackend:
             py.test.skip("not implemented with the ctypes backend")
         ffi = FFI(backend=self.Backend())
-        ffi.cdef("long left; int test_getting_errno(void);")
+        ffi.cdef("extern long left; int test_getting_errno(void);")
         lib = ffi.dlopen(self.module)
         lib.left = 123456
         p = ffi.addressof(lib, "left")
diff --git a/testing/cffi0/test_parsing.py b/testing/cffi0/test_parsing.py
index 2c29b86..3fc3783 100644
--- a/testing/cffi0/test_parsing.py
+++ b/testing/cffi0/test_parsing.py
@@ -324,6 +324,7 @@ def test_WPARAM_on_windows():
     assert value == sys.maxsize * 2 - 40
 
 def test__is_constant_globalvar():
+    import warnings
     for input, expected_output in [
         ("int a;",          False),
         ("const int a;",    True),
@@ -341,10 +342,13 @@ def test__is_constant_globalvar():
         ("const int a[5][6];", False),
         ]:
         ffi = FFI()
-        ffi.cdef(input)
+        with warnings.catch_warnings(record=True) as log:
+            warnings.simplefilter("always")
+            ffi.cdef(input)
         declarations = ffi._parser._declarations
         assert ('constant a' in declarations) == expected_output
         assert ('variable a' in declarations) == (not expected_output)
+        assert len(log) == (1 - expected_output)
 
 def test_restrict():
     from cffi import model
@@ -354,7 +358,7 @@ def test_restrict():
         ("int *a;",            False),
         ]:
         ffi = FFI()
-        ffi.cdef(input)
+        ffi.cdef("extern " + input)
         tp, quals = ffi._parser._declarations['variable a']
         assert bool(quals & model.Q_RESTRICT) == expected_output
 
diff --git a/testing/cffi0/test_verify.py b/testing/cffi0/test_verify.py
index b1033c5..f4ea092 100644
--- a/testing/cffi0/test_verify.py
+++ b/testing/cffi0/test_verify.py
@@ -286,7 +286,7 @@ def test_all_integer_and_float_types():
 def test_var_signed_integer_types():
     ffi = FFI()
     lst = all_signed_integer_types(ffi)
-    csource = "\n".join(["%s somevar_%s;" % (tp, tp.replace(' ', '_'))
+    csource = "\n".join(["static %s somevar_%s;" % (tp, tp.replace(' ', '_'))
                          for tp in lst])
     ffi.cdef(csource)
     lib = ffi.verify(csource)
@@ -305,7 +305,7 @@ def test_var_signed_integer_types():
 def test_var_unsigned_integer_types():
     ffi = FFI()
     lst = all_unsigned_integer_types(ffi)
-    csource = "\n".join(["%s somevar_%s;" % (tp, tp.replace(' ', '_'))
+    csource = "\n".join(["static %s somevar_%s;" % (tp, tp.replace(' ', '_'))
                          for tp in lst])
     ffi.cdef(csource)
     lib = ffi.verify(csource)
@@ -817,8 +817,8 @@ def test_define_int():
 
 def test_access_variable():
     ffi = FFI()
-    ffi.cdef("int foo(void);\n"
-             "int somenumber;")
+    ffi.cdef("static int foo(void);\n"
+             "static int somenumber;")
     lib = ffi.verify("""
         static int somenumber = 2;
         static int foo(void) {
@@ -835,7 +835,7 @@ def test_access_variable():
 def test_access_address_of_variable():
     # access the address of 'somenumber': need a trick
     ffi = FFI()
-    ffi.cdef("int somenumber; static int *const somenumberptr;")
+    ffi.cdef("static int somenumber; static int *const somenumberptr;")
     lib = ffi.verify("""
         static int somenumber = 2;
         #define somenumberptr (&somenumber)
@@ -848,7 +848,7 @@ def test_access_address_of_variable():
 def test_access_array_variable(length=5):
     ffi = FFI()
     ffi.cdef("int foo(int);\n"
-             "int somenumber[%s];" % (length,))
+             "static int somenumber[%s];" % (length,))
     lib = ffi.verify("""
         static int somenumber[] = {2, 2, 3, 4, 5};
         static int foo(int i) {
@@ -880,7 +880,7 @@ def test_access_struct_variable():
     ffi = FFI()
     ffi.cdef("struct foo { int x; ...; };\n"
              "int foo(int);\n"
-             "struct foo stuff;")
+             "static struct foo stuff;")
     lib = ffi.verify("""
         struct foo { int x, y, z; };
         static struct foo stuff = {2, 5, 8};
@@ -904,9 +904,9 @@ def test_access_struct_variable():
 
 def test_access_callback():
     ffi = FFI()
-    ffi.cdef("int (*cb)(int);\n"
-             "int foo(int);\n"
-             "void reset_cb(void);")
+    ffi.cdef("static int (*cb)(int);\n"
+             "static int foo(int);\n"
+             "static void reset_cb(void);")
     lib = ffi.verify("""
         static int g(int x) { return x * 7; }
         static int (*cb)(int);
@@ -922,9 +922,9 @@ def test_access_callback():
 def test_access_callback_function_typedef():
     ffi = FFI()
     ffi.cdef("typedef int mycallback_t(int);\n"
-             "mycallback_t *cb;\n"
-             "int foo(int);\n"
-             "void reset_cb(void);")
+             "static mycallback_t *cb;\n"
+             "static int foo(int);\n"
+             "static void reset_cb(void);")
     lib = ffi.verify("""
         static int g(int x) { return x * 7; }
         static int (*cb)(int);
@@ -1074,7 +1074,7 @@ def test_autofilled_struct_as_argument():
 def test_autofilled_struct_as_argument_dynamic():
     ffi = FFI()
     ffi.cdef("struct foo_s { long a; ...; };\n"
-             "int (*foo)(struct foo_s);")
+             "static int (*foo)(struct foo_s);")
     lib = ffi.verify("""
         struct foo_s {
             double b;
@@ -1083,7 +1083,7 @@ def test_autofilled_struct_as_argument_dynamic():
         int foo1(struct foo_s s) {
             return (int)s.a - (int)s.b;
         }
-        int (*foo)(struct foo_s s) = &foo1;
+        static int (*foo)(struct foo_s s) = &foo1;
     """)
     e = py.test.raises(NotImplementedError, lib.foo, "?")
     msg = ("ctype 'struct foo_s' not supported as argument.  It is a struct "
@@ -1453,7 +1453,7 @@ def test_bool():
         py.test.skip("_Bool not in MSVC")
     ffi = FFI()
     ffi.cdef("struct foo_s { _Bool x; };"
-             "_Bool foo(_Bool); _Bool (*foop)(_Bool);")
+             "_Bool foo(_Bool); static _Bool (*foop)(_Bool);")
     lib = ffi.verify("""
         struct foo_s { _Bool x; };
         int foo(int arg) {
@@ -1462,7 +1462,7 @@ def test_bool():
         _Bool _foofunc(_Bool x) {
             return !x;
         }
-        _Bool (*foop)(_Bool) = _foofunc;
+        static _Bool (*foop)(_Bool) = _foofunc;
     """)
     p = ffi.new("struct foo_s *")
     p.x = 1
@@ -1653,7 +1653,7 @@ def test_FILE_stored_in_stdout():
 
 def test_FILE_stored_explicitly():
     ffi = FFI()
-    ffi.cdef("int myprintf11(const char *, int); FILE *myfile;")
+    ffi.cdef("int myprintf11(const char *, int); extern FILE *myfile;")
     lib = ffi.verify("""
         #include <stdio.h>
         FILE *myfile;
@@ -1679,19 +1679,19 @@ def test_FILE_stored_explicitly():
 
 def test_global_array_with_missing_length():
     ffi = FFI()
-    ffi.cdef("int fooarray[];")
+    ffi.cdef("extern int fooarray[];")
     lib = ffi.verify("int fooarray[50];")
     assert repr(lib.fooarray).startswith("<cdata 'int *'")
 
 def test_global_array_with_dotdotdot_length():
     ffi = FFI()
-    ffi.cdef("int fooarray[...];")
+    ffi.cdef("extern int fooarray[...];")
     lib = ffi.verify("int fooarray[50];")
     assert repr(lib.fooarray).startswith("<cdata 'int[50]'")
 
 def test_bad_global_array_with_dotdotdot_length():
     ffi = FFI()
-    ffi.cdef("int fooarray[...];")
+    ffi.cdef("extern int fooarray[...];")
     py.test.raises(VerificationError, ffi.verify, "char fooarray[23];")
 
 def test_struct_containing_struct():
@@ -1812,7 +1812,7 @@ def test_string_to_voidp_arg():
 def test_callback_indirection():
     ffi = FFI()
     ffi.cdef("""
-        int (*python_callback)(int how_many, int *values);
+        static int (*python_callback)(int how_many, int *values);
         int (*const c_callback)(int,...);   /* pass this ptr to C routines */
         int some_c_function(int(*cb)(int,...));
     """)
@@ -1946,24 +1946,24 @@ def test_typeof_func_with_struct_argument():
 
 def test_bug_const_char_ptr_array_1():
     ffi = FFI()
-    ffi.cdef("""const char *a[...];""")
+    ffi.cdef("""extern const char *a[...];""")
     lib = ffi.verify("""const char *a[5];""")
     assert repr(ffi.typeof(lib.a)) == "<ctype 'char *[5]'>"
 
 def test_bug_const_char_ptr_array_2():
     from cffi import FFI     # ignore warnings
     ffi = FFI()
-    ffi.cdef("""const int a[];""")
+    ffi.cdef("""extern const int a[];""")
     lib = ffi.verify("""const int a[5];""")
     assert repr(ffi.typeof(lib.a)) == "<ctype 'int *'>"
 
 def _test_various_calls(force_libffi):
     cdef_source = """
-    int xvalue;
-    long long ivalue, rvalue;
-    float fvalue;
-    double dvalue;
-    long double Dvalue;
+    extern int xvalue;
+    extern long long ivalue, rvalue;
+    extern float fvalue;
+    extern double dvalue;
+    extern long double Dvalue;
     signed char tf_bb(signed char x, signed char c);
     unsigned char tf_bB(signed char x, unsigned char c);
     short tf_bh(signed char x, short c);
@@ -2147,7 +2147,7 @@ def test_verify_dlopen_flags():
     # exported symbols as well.  So we must not export a simple name
     # like 'foo'!
     ffi1 = FFI()
-    ffi1.cdef("int foo_verify_dlopen_flags;")
+    ffi1.cdef("extern int foo_verify_dlopen_flags;")
 
     lib1 = ffi1.verify("int foo_verify_dlopen_flags;",
                        flags=ffi1.RTLD_GLOBAL | ffi1.RTLD_LAZY)
@@ -2161,7 +2161,7 @@ def test_verify_dlopen_flags():
 def get_second_lib():
     # Hack, using modulename makes the test fail
     ffi2 = FFI()
-    ffi2.cdef("int foo_verify_dlopen_flags;")
+    ffi2.cdef("extern int foo_verify_dlopen_flags;")
     lib2 = ffi2.verify("int foo_verify_dlopen_flags;",
                        flags=ffi2.RTLD_GLOBAL | ffi2.RTLD_LAZY)
     return lib2