From 990c91f2a7b3eece87477e3dd9af8463993c7c03 Mon Sep 17 00:00:00 2001
From: Michael Natterer <mitch@gimp.org>
Date: Sun, 8 Nov 2015 01:04:16 +0100
Subject: [PATCH] m4macros: make detectcflags.m4 more reliable

GIMP_DETECT_CFLAGS: pass -Werror to the compiler when checking for
flags, so the macro fails if passing a flag only warns but doesn't
cause the compiler to fail. Before, the compiler would warn about the
flag for each file compiled.
---
 m4macros/detectcflags.m4 | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/m4macros/detectcflags.m4 b/m4macros/detectcflags.m4
index ad8a099873..ee33456a1d 100644
--- a/m4macros/detectcflags.m4
+++ b/m4macros/detectcflags.m4
@@ -7,7 +7,7 @@ AC_DEFUN([GIMP_DETECT_CFLAGS],
   for flag in $2; do
     if test -z "[$]$1"; then
       $1_save_CFLAGS="$CFLAGS"
-      CFLAGS="$CFLAGS $flag"
+      CFLAGS="$CFLAGS -Werror $flag"
       AC_MSG_CHECKING([whether [$]CC understands [$]flag])
       AC_TRY_COMPILE([], [], [$1_works=yes], [$1_works=no])
       AC_MSG_RESULT([$]$1_works)