diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h
index d61a6f0..15004d2 100644
--- a/tools/perf/util/util.h
+++ b/tools/perf/util/util.h
@@ -39,10 +39,6 @@
 /* Approximation of the length of the decimal representation of this type. */
 #define decimal_length(x)	((int)(sizeof(x) * 2.56 + 0.5) + 1)
 
-#if !defined(__APPLE__) && !defined(__FreeBSD__)  && !defined(__USLC__) && !defined(_M_UNIX)
-#define _XOPEN_SOURCE 600 /* glibc2 and AIX 5.3L need 500, OpenBSD needs 600 for S_ISLNK() */
-#define _XOPEN_SOURCE_EXTENDED 1 /* AIX 5.3L needs this */
-#endif
 #define _ALL_SOURCE 1
 #define _GNU_SOURCE 1
 #define _BSD_SOURCE 1