* c-decl.c (diagnose_mismatched_decls): Give an error for

	redefining a typedef with variably modified type.

testsuite:
	* gcc.dg/c1x-typedef-1.c: Expect errors for redefinitions of
	variably modified typedefs.
	* gcc.dg/c1x-typedef-2.c: Remove.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@171172 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 6 insertions, 10 deletions

diff --git a/gcc/c-decl.c b/gcc/c-decl.c
index 8f9c4440048..4e82f2844a8 100644
--- a/gcc/c-decl.c
+++ b/gcc/c-decl.c
@@ -1813,20 +1813,16 @@ diagnose_mismatched_decls (tree newdecl, tree olddecl,
 	  || TREE_NO_WARNING (olddecl))
 	return true;  /* Allow OLDDECL to continue in use.  */
 
-      if (pedantic && !flag_isoc1x)
+      if (variably_modified_type_p (newtype, NULL))
 	{
-	  pedwarn (input_location, OPT_pedantic,
-		   "redefinition of typedef %q+D", newdecl);
+	  error ("redefinition of typedef %q+D with variably modified type",
+		 newdecl);
 	  locate_old_decl (olddecl);
 	}
-      else if (variably_modified_type_p (newtype, NULL))
+      else if (pedantic && !flag_isoc1x)
 	{
-	  /* Whether there is a constraint violation for the types not
-	     being the same cannot be determined at compile time; a
-	     warning that there may be one at runtime is considered
-	     appropriate (WG14 reflector message 11743, 8 May 2009).  */
-	  warning (0, "redefinition of typedef %q+D may be a constraint "
-		   "violation at runtime", newdecl);
+	  pedwarn (input_location, OPT_pedantic,
+		   "redefinition of typedef %q+D", newdecl);
 	  locate_old_decl (olddecl);
 	}