re PR c/63480 (-Wmissing-field-initializers should not warn about intentionally…

re PR c/63480 (-Wmissing-field-initializers should not warn about intentionally empty initializers (or that should be a separate option))

	PR c/63480
	* c-typeck.c (pop_init_level): Don't warn about initializing
	with { }.

	* gcc.dg/pr63480.c: New test.

From-SVN: r216031

gcc/c/ChangeLog

+2014-10-09  Marek Polacek  <polacek@redhat.com>
+
+	PR c/63480
+	* c-typeck.c (pop_init_level): Don't warn about initializing
+	with { }.
+
 2014-10-07  Marek Polacek  <polacek@redhat.com>
 
 	PR c/59717

gcc/c/c-typeck.c

@@ -7436,7 +7436,11 @@ pop_init_level (location_t loc, int implicit,
 	}
     }
 
-  if (vec_safe_length (constructor_elements) != 1)
+  /* Initialization with { } counts as zeroinit.  */
+  if (vec_safe_length (constructor_elements) == 0)
+    constructor_zeroinit = 1;
+  /* If the constructor has more than one element, it can't be { 0 }.  */
+  else if (vec_safe_length (constructor_elements) != 1)
     constructor_zeroinit = 0;
 
   /* Warn when some structs are initialized with direct aggregation.  */
@@ -7463,7 +7467,7 @@ pop_init_level (location_t loc, int implicit,
 	    /* Do not warn if this level of the initializer uses member
 	       designators; it is likely to be deliberate.  */
 	    && !constructor_designated
-	    /* Do not warn about initializing with ` = {0}'.  */
+	    /* Do not warn about initializing with { 0 } or with { }.  */
 	    && !constructor_zeroinit)
 	  {
 	    if (warning_at (input_location, OPT_Wmissing_field_initializers,

gcc/testsuite/ChangeLog

+2014-10-09  Marek Polacek  <polacek@redhat.com>
+
+	PR c/63480
+	* gcc.dg/pr63480.c: New test.
+
 2014-10-09  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/63445

gcc/testsuite/gcc.dg/pr63480.c

+/* PR c/63480 */
+/* { dg-do compile } */
+/* { dg-options "-Wmissing-field-initializers" } */
+
+/* Test that we don't warn about initializing with { }.  */
+
+struct S { int a, b, c; } s = { };
+
+void
+foo (void)
+{
+  struct S s = { }; 
+  struct S s2 = (struct S){ };
+}