From 2c0e997ee812a1754c783531a1c4c25b75389822 Mon Sep 17 00:00:00 2001
From: Denis Kenzior <denkenz@gmail.com>
Date: Fri, 1 Aug 2014 09:47:33 -0500
Subject: [PATCH] build: Avoid redefining _FORTIFY_SOURCE

Gentoo (and others) define _FORTIFY_SOURCE=2 by default.  Since we
always define it as well, this results in redefinition warnings &
configure failure.
---
 acinclude.m4 | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/acinclude.m4 b/acinclude.m4
index f15dfd1a..955e8645 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -12,7 +12,8 @@ AC_DEFUN([AC_PROG_CC_PIE], [
 
 AC_DEFUN([COMPILER_FLAGS], [
 	if (test "${CFLAGS}" = ""); then
-		CFLAGS="-Wall -O2 -D_FORTIFY_SOURCE=2 -fsigned-char"
+		CFLAGS="-Wall -O2 -fsigned-char "
+		CFLAGS+=" -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2"
 	fi
 	if (test "$USE_MAINTAINER_MODE" = "yes"); then
 		CFLAGS+=" -Werror -Wextra"