wrap some #define with #ifndef

src/api/pmi.c

@@ -79,7 +79,9 @@
  *  with SLURM; if not, write to the Free Software Foundation, Inc.,
  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA.
 \*****************************************************************************/
-#define _GNU_SOURCE
+#ifndef   _GNU_SOURCE
+#  define _GNU_SOURCE
+#endif
 
 #include <pthread.h>
 #include <signal.h>

src/plugins/proctrack/pgid/proctrack_pgid.c

@@ -46,7 +46,9 @@
 #  include <inttypes.h>
 #endif
 
-#define __USE_XOPEN_EXTENDED /* getpgid */
+#ifndef   __USE_XOPEN_EXTENDED
+#  define __USE_XOPEN_EXTENDED /* getpgid */
+#endif
 #include <unistd.h>
 
 #include <sys/types.h>

src/plugins/task/affinity/affinity.h

@@ -61,8 +61,13 @@
 #include <sys/utsname.h>
 #include <unistd.h>
 
-#define _GNU_SOURCE
-#define __USE_GNU
+#ifndef   _GNU_SOURCE
+#  define _GNU_SOURCE
+#endif
+#ifndef   __USE_GNU
+#define   __USE_GNU
+#endif
+
 #include <sched.h> /* SMB */
 
 #ifdef HAVE_STDLIB_H