From 029d1e16b9a55e77872dac4fab87692b8c7dc2d0 Mon Sep 17 00:00:00 2001
From: Jerome Robert <jeromerobert@gmx.com>
Date: Wed, 14 Jul 2021 12:20:57 +0200
Subject: [PATCH] Avoid redefinition of _GNU_SOURCE

* _GNU_SOURCE may have been set by the application and redefinition
  trigger warnings or error with -Werror
* Fix for 220f6a1c5
---
 openblas_config_template.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/openblas_config_template.h b/openblas_config_template.h
index 1e17c9a16..6a7382108 100644
--- a/openblas_config_template.h
+++ b/openblas_config_template.h
@@ -99,6 +99,8 @@ typedef int blasint;
 
 /* Inclusion of Linux-specific header is needed for definition of cpu_set_t. */
 #ifdef OPENBLAS_OS_LINUX
-#define _GNU_SOURCE
+#ifndef _GNU_SOURCE
+ #define _GNU_SOURCE
+#endif
 #include <sched.h>
 #endif