From 7a4254dda1c0e514cfa0dbeb7f1b236688eb90fc Mon Sep 17 00:00:00 2001
From: Ming Chen <ming.a.chen@intel.com>
Date: Tue, 17 Mar 2020 10:42:32 +0800
Subject: [PATCH] m4macros: update ax_gcc_func_attribute.m4 to serial 12

The serial 7 of m4macros/ax_gcc_func_attribute.m4 has an issue that when
Wstrict-prototypes is used with gcc, the attribute detection always
fails even if the attribute is actually supported. In such case the fish
cache will never be constructed. It's fixed in serial 12 of the macro in
autoconf-archive and this change updates the one distributed with GIMP
to serial 12.
---
 m4macros/ax_gcc_func_attribute.m4 | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/m4macros/ax_gcc_func_attribute.m4 b/m4macros/ax_gcc_func_attribute.m4
index 077962f837..da2b1acceb 100644
--- a/m4macros/ax_gcc_func_attribute.m4
+++ b/m4macros/ax_gcc_func_attribute.m4
@@ -38,9 +38,11 @@
 #    dllimport
 #    error
 #    externally_visible
+#    fallthrough
 #    flatten
 #    format
 #    format_arg
+#    gnu_format
 #    gnu_inline
 #    hot
 #    ifunc
@@ -53,6 +55,8 @@
 #    nothrow
 #    optimize
 #    pure
+#    sentinel
+#    sentinel_position
 #    unused
 #    used
 #    visibility
@@ -74,7 +78,7 @@
 #   and this notice are preserved.  This file is offered as-is, without any
 #   warranty.
 
-#serial 7
+#serial 12
 
 AC_DEFUN([AX_GCC_FUNC_ATTRIBUTE], [
     AS_VAR_PUSHDEF([ac_var], [ax_cv_have_func_attribute_$1])
@@ -128,12 +132,18 @@ AC_DEFUN([AX_GCC_FUNC_ATTRIBUTE], [
                 [externally_visible], [
                     int foo( void ) __attribute__(($1));
                 ],
+                [fallthrough], [
+                    int foo( void ) {switch (0) { case 1: __attribute__(($1)); case 2: break ; }};
+                ],
                 [flatten], [
                     int foo( void ) __attribute__(($1));
                 ],
                 [format], [
                     int foo(const char *p, ...) __attribute__(($1(printf, 1, 2)));
                 ],
+                [gnu_format], [
+                    int foo(const char *p, ...) __attribute__((format(gnu_printf, 1, 2)));
+                ],
                 [format_arg], [
                     char *foo(const char *p) __attribute__(($1(1)));
                 ],
@@ -175,6 +185,12 @@ AC_DEFUN([AX_GCC_FUNC_ATTRIBUTE], [
                 [pure], [
                     int foo( void ) __attribute__(($1));
                 ],
+                [sentinel], [
+                    int foo(void *p, ...) __attribute__(($1));
+                ],
+                [sentinel_position], [
+                    int foo(void *p, ...) __attribute__(($1(1)));
+                ],
                 [returns_nonnull], [
                     void *foo( void ) __attribute__(($1));
                 ],
@@ -212,7 +228,7 @@ AC_DEFUN([AX_GCC_FUNC_ATTRIBUTE], [
             dnl GCC doesn't exit with an error if an unknown attribute is
             dnl provided but only outputs a warning, so accept the attribute
             dnl only if no warning were issued.
-            [AS_IF([test -s conftest.err],
+            [AS_IF([grep -- -Wattributes conftest.err],
                 [AS_VAR_SET([ac_var], [no])],
                 [AS_VAR_SET([ac_var], [yes])])],
             [AS_VAR_SET([ac_var], [no])])