invoke.texi: Document -Wc99-c11-compat.

	* doc/invoke.texi: Document -Wc99-c11-compat.
c-family/
	* c.opt (Wc99-c11-compat): New option.
c/
	* c-decl.c (diagnose_mismatched_decls): Unconditionally call
	pedwarn_c99 instead of pedwarn.
	(grokfield): Likewise.
	(warn_defaults_to): New function.
	(grokdeclarator): Call warn_defaults_to instead of pedwarn_c99.
	Unconditionally call pedwarn_c99 instead of pedwarn.
	(start_function): Call warn_defaults_to instead of pedwarn_c99.
	(declspecs_add_scspec): Call pedwarn_c99 instead of pedwarn, don't
	check flag_isoc11 before.
	* c-errors.c (pedwarn_c99): Change the return type to bool.
	Handle -Wc99-c11-compat.
	* c-parser.c (disable_extension_diagnostics): Handle
	warn_c99_c11_compat.
	(restore_extension_diagnostics): Likewise.
	(c_parser_static_assert_declaration_no_semi): Call pedwarn_c99
	instead of pedwarn, don't check flag_isoc11 before.
	(c_parser_declspecs): Likewise.
	(c_parser_alignas_specifier): Likewise.
	(c_parser_alignof_expression): Likewise.
	(c_parser_generic_selection): Likewise.
	* c-tree.h (pedwarn_c99): Update declaration.
	* c-typeck.c (c_finish_return): Call pedwarn or warning_at instead
	of pedwarn_c99.
testsuite/
	* gcc.dg/Wc99-c11-compat-1.c: New test.
	* gcc.dg/Wc99-c11-compat-2.c: New test.
	* gcc.dg/Wc99-c11-compat-3.c: New test.
	* gcc.dg/Wc99-c11-compat-4.c: New test.
	* gcc.dg/Wc99-c11-compat-5.c: New test.
	* gcc.dg/Wc99-c11-compat-6.c: New test.
	* gcc.dg/Wc99-c11-compat-7.c: New test.

From-SVN: r214133

1 files changed, 28 insertions, 6 deletions

diff --git a/gcc/c/c-errors.c b/gcc/c/c-errors.c
index 89393b9..c1f9c35 100644
--- a/gcc/c/c-errors.c
+++ b/gcc/c/c-errors.c
@@ -29,20 +29,42 @@ along with GCC; see the file COPYING3.  If not see
 #include "diagnostic.h"
 #include "opts.h"
 
-/* Issue an ISO C99 pedantic warning MSGID.  */
+/* Issue an ISO C99 pedantic warning MSGID if -pedantic outside C11 mode,
+   otherwise issue warning MSGID if -Wc99-c11-compat is specified.
+   This function is supposed to be used for matters that are allowed in
+   ISO C11 but not supported in ISO C99, thus we explicitly don't pedwarn
+   when C11 is specified.  */
 
-void
+bool
 pedwarn_c99 (location_t location, int opt, const char *gmsgid, ...)
 {
   diagnostic_info diagnostic;
   va_list ap;
+  bool warned = false;
 
   va_start (ap, gmsgid);
-  diagnostic_set_info (&diagnostic, gmsgid, &ap, location,
-		       flag_isoc99 ? DK_PEDWARN : DK_WARNING);
-  diagnostic.option_index = opt;
-  report_diagnostic (&diagnostic);
+  /* If desired, issue the C99/C11 compat warning, which is more specific
+     than -pedantic.  */
+  if (warn_c99_c11_compat > 0)
+    {
+      diagnostic_set_info (&diagnostic, gmsgid, &ap, location,
+			   (pedantic && !flag_isoc11)
+			   ? DK_PEDWARN : DK_WARNING);
+      diagnostic.option_index = OPT_Wc99_c11_compat;
+      warned = report_diagnostic (&diagnostic);
+    }
+  /* -Wno-c99-c11-compat suppresses even the pedwarns.  */
+  else if (warn_c99_c11_compat == 0)
+    ;
+  /* For -pedantic outside C11, issue a pedwarn.  */
+  else if (pedantic && !flag_isoc11)
+    {
+      diagnostic_set_info (&diagnostic, gmsgid, &ap, location, DK_PEDWARN);
+      diagnostic.option_index = opt;
+      warned = report_diagnostic (&diagnostic);
+    }
   va_end (ap);
+  return warned;
 }
 
 /* Issue an ISO C90 pedantic warning MSGID if -pedantic outside C99 mode,