[compiler-rt] [sanitizer_common] Older Haiku needs _GNU_SOURCE (PR #156291)

[Brad Smith via llvm-commits]

https://github.com/brad0 created https://github.com/llvm/llvm-project/pull/156291

None

>From 94509cf96b9d790913381f3fb7e5bc402dd2a3cb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=B4me=20Duval?= <jerome.duval at gmail.com>
Date: Mon, 1 Sep 2025 03:23:50 -0400
Subject: [PATCH] [sanitizer_common] Older Haiku needs _GNU_SOURCE

---
 compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
index f5cb85bc1bf30..530ff90c4cd16 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
@@ -29,6 +29,7 @@
 #  include "sanitizer_solaris.h"
 
 #  if SANITIZER_HAIKU
+#    define _GNU_SOURCE
 #    define _DEFAULT_SOURCE
 #  endif