[PATCH] Fix _XOPEN_SOURCE problem on DragonFly

[YONETANI Tomokazu <qhwt+git@les.ath.cx>]

Hi.
DragonFly has the same problem that FreeBSD used to have.  Since the
return value of implicitly declared functions defaults to int, it can
cause disasters on architectures where sizeof(int) < sizeof(void *).
The patch below should address this issue.

Best regards,
YONETANI Tomokazu.

diff --git a/git-compat-util.h b/git-compat-util.h
index a3c4537..e292926 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -55,7 +55,8 @@
 # else
 # define _XOPEN_SOURCE 500
 # endif
-#elif !defined(__APPLE__) && !defined(__FreeBSD__)  && !defined(__USLC__) && !defined(_M_UNIX) && !defined(sgi)
+#elif !defined(__APPLE__) && !defined(__FreeBSD__) && !defined(__USLC__) && \
+      !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