From: Andrii Nakryiko <andriin@fb.com>
Date: Mon, 1 Jun 2020 13:26:01 -0700
Subject: libbpf: Add _GNU_SOURCE for reallocarray to ringbuf.c
Patch-mainline: v5.8-rc1
Git-commit: febeb6dff7beafcaf89521f6c8ff7b0adac08d54
References: bsc#1177028

On systems with recent enough glibc, reallocarray compat won't kick in, so
reallocarray() itself has to come from stdlib.h include. But _GNU_SOURCE is
necessary to enable it. So add it.

Fixes: bf99c936f947 ("libbpf: Add BPF ring buffer support")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200601202601.2139477-1-andriin@fb.com
Acked-by: Gary Lin <glin@suse.com>
---
 tools/lib/bpf/ringbuf.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/tools/lib/bpf/ringbuf.c
+++ b/tools/lib/bpf/ringbuf.c
@@ -4,6 +4,9 @@
  *
  * Copyright (C) 2020 Facebook, Inc.
  */
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
 #include <stdlib.h>
 #include <stdio.h>
 #include <errno.h>