re PR c/44772 (-Wc++-compat warns incorrectly for anonymous unions)

	PR c/44772
	* c-decl.c (warn_cxx_compat_finish_struct): Don't call
	pointer_set_contains if DECL_NAME is NULL.

	* gcc.dg/Wcxx-compat-21.c: New test.

From-SVN: r166384

gcc/ChangeLog

+2010-11-05  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c/44772
+	* c-decl.c (warn_cxx_compat_finish_struct): Don't call
+	pointer_set_contains if DECL_NAME is NULL.
+
 2010-11-05  Ian Lance Taylor  <iant@google.com>
 
 	PR target/46084

gcc/c-decl.c

@@ -6877,7 +6877,8 @@ warn_cxx_compat_finish_struct (tree fieldlist)
 
       for (x = fieldlist; x != NULL_TREE; x = DECL_CHAIN (x))
 	{
-	  if (pointer_set_contains (tset, DECL_NAME (x)))
+	  if (DECL_NAME (x) != NULL_TREE
+	      && pointer_set_contains (tset, DECL_NAME (x)))
 	    {
 	      warning_at (DECL_SOURCE_LOCATION (x), OPT_Wc___compat,
 			  ("using %qD as both field and typedef name is "

gcc/testsuite/ChangeLog

+2010-11-05  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c/44772
+	* gcc.dg/Wcxx-compat-21.c: New test.
+
 2010-11-05  Ian Lance Taylor  <iant@google.com>
 
 	PR target/46084

gcc/testsuite/gcc.dg/Wcxx-compat-21.c

+/* PR c/44772 */
+/* { dg-do compile } */
+/* { dg-options "-Wc++-compat" } */
+
+typedef enum { E1, E2 } E;
+
+typedef struct
+{
+  E e;
+  union
+  {
+    int i;
+    char *c;
+  };			/* { dg-bogus "as both field and typedef name" } */
+} S;
+
+S s;
+
+typedef int T;
+
+struct U
+{
+  T t;
+  union { int i; };	/* { dg-bogus "as both field and typedef name" } */
+};