PR c/39564

	* c-decl.c (grokdeclarator): Diagnose declarations of functions
	with variably modified return type and no storage class
	specifiers, except for the case of nested functions.  Distinguish
	extern declarations of functions with variably modified return
	types from those of objects with variably modified types.

testsuite:
	* gcc.dg/vla-19.c: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@146778 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 47f98fa..c3a2d00 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2009-04-25  Joseph Myers  <joseph@codesourcery.com>
+
+       PR c/39564
+       * c-decl.c (grokdeclarator): Diagnose declarations of functions
+       with variably modified return type and no storage class
+       specifiers, except for the case of nested functions.  Distinguish
+       extern declarations of functions with variably modified return
+       types from those of objects with variably modified types.
+
 2009-04-25  Jan Hubicka  <jh@suse.cz>
 
        * tree.c (list_equal_p): New function.

diff --git a/gcc/c-decl.c b/gcc/c-decl.c
index d2dbfbe..9693a34 100644 (file)
--- a/gcc/c-decl.c
+++ b/gcc/c-decl.c
@@ -5012,11 +5012,17 @@ grokdeclarator (const struct c_declarator *declarator,
          DECL_TLS_MODEL (decl) = decl_default_tls_model (decl);
       }
 
-    if (storage_class == csc_extern
+    if ((storage_class == csc_extern
+        || (storage_class == csc_none
+            && TREE_CODE (type) == FUNCTION_TYPE
+            && !funcdef_flag))
        && variably_modified_type_p (type, NULL_TREE))
       {
        /* C99 6.7.5.2p2 */
-       error ("object with variably modified type must have no linkage");
+       if (TREE_CODE (type) == FUNCTION_TYPE)
+         error ("non-nested function with variably modified type");
+       else
+         error ("object with variably modified type must have no linkage");
       }
 
     /* Record `register' declaration for warnings on &

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index f2fdc93..c9cfd92 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,10 @@
 2009-04-25  Joseph Myers  <joseph@codesourcery.com>
 
+       PR c/39564
+       * gcc.dg/vla-19.c: New test.
+
+2009-04-25  Joseph Myers  <joseph@codesourcery.com>
+
        PR preprocessor/39559
        * gcc.dg/c99-intconst-2.c: New test.
 

diff --git a/gcc/testsuite/gcc.dg/vla-19.c b/gcc/testsuite/gcc.dg/vla-19.c
new file mode 100644 (file)
index 0000000..83093c9
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vla-19.c
@@ -0,0 +1,32 @@
+/* Test diagnostics for variably modified function return types.  PR
+   39564.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c99" } */
+
+int a;
+
+void
+f1 (void)
+{
+  typedef int T[a];
+  extern T *g1 (void); /* { dg-error "non-nested function with variably modified type" } */
+}
+
+void
+f2 (void)
+{
+  extern int (*g2 (void))[a]; /* { dg-error "non-nested function with variably modified type" } */
+}
+
+void
+f3 (void)
+{
+  typedef int T[a];
+  T *g3 (void); /* { dg-error "non-nested function with variably modified type" } */
+}
+
+void
+f4 (void)
+{
+  int (*g4 (void))[a]; /* { dg-error "non-nested function with variably modified type" } */
+}