From 4097f57573bc5d7a705e5de09ec148d86e5fd925 Mon Sep 17 00:00:00 2001
From: Adrian Ratiu <adrian.ratiu@collabora.com>
Date: Tue, 16 Feb 2021 20:21:21 +0200
Subject: [PATCH] missing.h: workaround autotools renameat2 glibc 2.28
 misdetection

When building udev/systemd v225 on top of glibc 2.28 or newer,
the following error occurs:

error: static declaration of 'renameat2' follows non-static declaration

This is because the old autotools infrastructure incorrectly
detects the presence of the glibc renameat2 wrapper and tries to
replace it with a compatible systemd-internal one. We avoid this
situation by guarding the systemd wrapper with a __GLIBC__ macro.

This patch should be dropped once systemd/udev is upgraded past
the move to meson upstream which also has heavy syscall wrapper
tree-wide refactorings.

Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
---
 src/basic/missing.h | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/basic/missing.h b/src/basic/missing.h
index 34ab0254dd..87bce481ec 100644
--- a/src/basic/missing.h
+++ b/src/basic/missing.h
@@ -984,7 +984,11 @@ static inline pid_t raw_getpid(void) {
 #endif
 }
 
-#if !HAVE_DECL_RENAMEAT2
+/* autotools detection is broken for this path with newer glibc and in the
+ * meantime systemd dropped autotools in favor of meson, so autotools bugs are
+ * not fixed anymore; systemd needs upgrading to be able to drop this #if hack.
+ */
+#if !HAVE_DECL_RENAMEAT2 && !(__GLIBC__ >= 2 && __GLIBC_MINOR__ >= 28)
 
 #ifndef __NR_renameat2
 #  if defined __x86_64__
-- 
2.30.1