2014-10-19  Marek Polacek  <polacek@redhat.com>

	PR c/63567
	* c-typeck.c (output_init_element): Allow initializing objects with
	static storage duration with compound literals even in C99 and add
	pedwarn for it.

--- gcc/c/c-typeck.c
+++ gcc/c/c-typeck.c
@@ -8251,11 +8251,14 @@ output_init_element (location_t loc, tree value, tree origtype,
     value = array_to_pointer_conversion (input_location, value);
 
   if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
-      && require_constant_value && !flag_isoc99 && pending)
+      && require_constant_value && pending)
     {
       /* As an extension, allow initializing objects with static storage
 	 duration with compound literals (which are then treated just as
 	 the brace enclosed list they contain).  */
+      if (flag_isoc99)
+	pedwarn_init (input_location, OPT_Wpedantic, "initializer element is not "
+		      "constant");
       tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
       value = DECL_INITIAL (decl);
     }
--- /dev/null
+++ gcc/testsuite/gcc.dg/pr63567-3.c
@@ -0,0 +1,7 @@
+/* PR c/63567 */
+/* { dg-do compile } */
+/* { dg-options "" } */
+
+struct T { int i; };
+struct S { struct T t; };
+struct S s = { .t = { (int) { 1 } } };
--- /dev/null
+++ gcc/testsuite/gcc.dg/pr63567-4.c
@@ -0,0 +1,7 @@
+/* PR c/63567 */
+/* { dg-do compile } */
+/* { dg-options "-Wpedantic -std=gnu99" } */
+
+struct T { int i; };
+struct S { struct T t; };
+struct S s = { .t = { (int) { 1 } } }; /* { dg-warning "initializer element is not constant|initialization" } */