diff --git a/git-compat-util.h b/git-compat-util.h
index 7e62b552700a580646dbb6a8921c40761d6b57a2..b96912b5d36e971212e219f038b62bfcb7bdbd14 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -56,7 +56,7 @@
 # define _XOPEN_SOURCE 500
 # endif
 #elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && \
-      !defined(_M_UNIX) && !defined(sgi) && !defined(__DragonFly__)
+      !defined(_M_UNIX) && !defined(__sgi) && !defined(__DragonFly__)
 #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