From 3f500e7202476500fdc70f98d796d4103705638f Mon Sep 17 00:00:00 2001
From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Tue, 18 May 2021 16:59:56 -0300
Subject: [PATCH] linux: Fix clock_getres fallback

The tst-timespec_getres (e5ac7bd679de5) triggers an issue on 32-bit
architecture on Linux older than 5.1, where the fallback syscall
is used.

Checked on powerpc-linux-gnu.
---
 sysdeps/unix/sysv/linux/clock_getres.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sysdeps/unix/sysv/linux/clock_getres.c b/sysdeps/unix/sysv/linux/clock_getres.c
index d560cd7c48..a9edec93e6 100644
--- a/sysdeps/unix/sysv/linux/clock_getres.c
+++ b/sysdeps/unix/sysv/linux/clock_getres.c
@@ -56,7 +56,7 @@ __clock_getres64 (clockid_t clock_id, struct __timespec64 *res)
 # else
   r = INLINE_SYSCALL_CALL (clock_getres, clock_id, &ts32);
 # endif
-  if (r == 0)
+  if (r == 0 && res != NULL)
     *res = valid_timespec_to_timespec64 (ts32);
 #endif