c-decl.c (grokfield): Don't allow typedefs for structures or unions with no tag by default.

	* c-decl.c (grokfield): Don't allow typedefs for structures or
	unions with no tag by default.
	* doc/extend.texi (Unnamed Fields): Update.

testsuite:
	* gcc.dg/c1x-anon-struct-1.c: Don't test use of typedefs.
	* gcc.dg/c1x-anon-struct-3.c: New test.
	* gcc.dg/anon-struct-11.c: Update.

From-SVN: r171170

gcc/ChangeLog

+2011-03-18  Joseph Myers  <joseph@codesourcery.com>
+
+	* c-decl.c (grokfield): Don't allow typedefs for structures or
+	unions with no tag by default.
+	* doc/extend.texi (Unnamed Fields): Update.
+
 2011-03-18  Uros Bizjak  <ubizjak@gmail.com>
 
 	* config/i386/i386.md (float<SSEMODEI24:mode><X87MODEF:mode>2):

gcc/c-decl.c

@@ -6674,11 +6674,14 @@ grokfield (location_t loc,
 		      || TREE_CODE (type) == UNION_TYPE);
       bool ok = false;
 
-      if (type_ok)
+      if (type_ok
+	  && (flag_ms_extensions
+	      || flag_plan9_extensions
+	      || !declspecs->typedef_p))
 	{
 	  if (flag_ms_extensions || flag_plan9_extensions)
 	    ok = true;
-	  else if (TYPE_NAME (TYPE_MAIN_VARIANT (type)) == NULL)
+	  else if (TYPE_NAME (type) == NULL)
 	    ok = true;
 	  else
 	    ok = false;

gcc/doc/extend.texi

@@ -13352,12 +13352,11 @@ The compiler gives errors for such constructs.
 @opindex fms-extensions
 Unless @option{-fms-extensions} is used, the unnamed field must be a
 structure or union definition without a tag (for example, @samp{struct
-@{ int a; @};}), or a @code{typedef} name for such a structure or
-union.  If @option{-fms-extensions} is used, the field may
+@{ int a; @};}).  If @option{-fms-extensions} is used, the field may
 also be a definition with a tag such as @samp{struct foo @{ int a;
 @};}, a reference to a previously defined structure or union such as
 @samp{struct foo;}, or a reference to a @code{typedef} name for a
-previously defined structure or union type with a tag.
+previously defined structure or union type.
 
 @opindex fplan9-extensions
 The option @option{-fplan9-extensions} enables

gcc/testsuite/ChangeLog

+2011-03-18  Joseph Myers  <joseph@codesourcery.com>
+
+	* gcc.dg/c1x-anon-struct-1.c: Don't test use of typedefs.
+	* gcc.dg/c1x-anon-struct-3.c: New test.
+	* gcc.dg/anon-struct-11.c: Update.
+
 2011-03-18  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
 
 	* gcc.dg/vect/slp-multitypes-2.c: Replace dg-do run with

gcc/testsuite/gcc.dg/anon-struct-11.c

@@ -50,7 +50,7 @@ struct E {
   struct F { char f; };	/* { dg-warning "does not declare anything" } */
   char c;
   union {
-    D;
+    D;			/* { dg-warning "does not declare anything" } */
   };
   char e;
 };
@@ -85,7 +85,7 @@ test2 (void)
   e.e = 5;
   f2 (&e);		/* { dg-warning "incompatible pointer type" } */
   f3 (&e);		/* { dg-warning "incompatible pointer type" } */
-  if (e.d != 4)
+  if (e.d != 4)		/* { dg-error "no member" } */
     abort ();
   if (e.f != 6)		/* { dg-error "no member" } */
     abort ();

gcc/testsuite/gcc.dg/c1x-anon-struct-1.c

@@ -4,20 +4,13 @@
 
 #include <stddef.h>
 
-typedef struct
-{
-  int i;
-} s0;
-
-typedef union
-{
-  int i;
-} u0;
-
 struct s1
 {
   int a;
-  u0;
+  union
+  {
+    int i;
+  };
   struct
   {
     int b;
@@ -27,7 +20,10 @@ struct s1
 union u1
 {
   int b;
-  s0;
+  struct
+  {
+    int i;
+  };
   union
   {
     int c;
@@ -44,7 +40,10 @@ struct s2
 
 struct s3
 {
-  u0;
+  union
+  {
+    int i;
+  };
 };
 
 struct s4

gcc/testsuite/gcc.dg/c1x-anon-struct-3.c

+/* Test for anonymous structures and unions in C1X.  Test for invalid
+   cases: typedefs disallowed by N1549.  */
+/* { dg-do compile } */
+/* { dg-options "-std=c1x -pedantic-errors" } */
+
+typedef struct
+{
+  int i;
+} s0;
+
+typedef union
+{
+  int i;
+} u0;
+
+struct s1
+{
+  int a;
+  u0; /* { dg-error "declaration does not declare anything" } */
+  struct
+  {
+    int b;
+  };
+};
+
+union u1
+{
+  int b;
+  s0; /* { dg-error "declaration does not declare anything" } */
+  union
+  {
+    int c;
+  };
+};