diff --git a/include/dieharder/libdieharder.h b/include/dieharder/libdieharder.h
index 2138ebf..f6d471b 100644
--- a/include/dieharder/libdieharder.h
+++ b/include/dieharder/libdieharder.h
@@ -6,6 +6,8 @@
 
 #include "copyright.h"
 
+#define _GNU_SOURCE
+
 /* To enable large file support */
 #define _FILE_OFFSET_BITS 64
 
@@ -16,13 +18,11 @@
 #include <sys/time.h>
 
 /* This turns on uint macro in c99 */
-#define __USE_MISC 1
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <unistd.h>
 
 /* This turns on M_PI in math.h */
-#define __USE_BSD 1
 #include <math.h>
 #include <limits.h>
 #include <gsl/gsl_rng.h>