From cff64d03c85696fab4fcb03313dd4d52f7fd50de Mon Sep 17 00:00:00 2001
From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Fri, 12 Aug 2022 12:44:15 +0200
Subject: [PATCH] git-compat-util: avoid redeclaring _DEFAULT_SOURCE

We are about to vendor in `mimalloc`'s source code which we will want to
include `compat/posix.h` after defining that constant.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 compat/posix.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/compat/posix.h b/compat/posix.h
index 245386fa4a..6a137480d9 100644
--- a/compat/posix.h
+++ b/compat/posix.h
@@ -70,7 +70,9 @@
 #define _ALL_SOURCE 1
 #define _GNU_SOURCE 1
 #define _BSD_SOURCE 1
+#ifndef _DEFAULT_SOURCE
 #define _DEFAULT_SOURCE 1
+#endif
 #define _NETBSD_SOURCE 1
 #define _SGI_SOURCE 1