From 9c1125c121423a9948fa39e71ef89ba4059a2fad Mon Sep 17 00:00:00 2001
From: Jonathan Wakely <jwakely@redhat.com>
Date: Wed, 4 Nov 2020 15:24:47 +0000
Subject: [PATCH] libstdc++: Fix test failure with --disable-linux-futex

As noted in PR 96817 this new test fails if the library is built without
futexes. That's expected of course, but we might as well fail more
obviously than a deadlock that eventually times out.

libstdc++-v3/ChangeLog:

	* testsuite/18_support/96817.cc: Fail fail if the library is
	configured to not use futexes.
---
 libstdc++-v3/testsuite/18_support/96817.cc | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libstdc++-v3/testsuite/18_support/96817.cc b/libstdc++-v3/testsuite/18_support/96817.cc
index f0332967831..4591a7288a5 100644
--- a/libstdc++-v3/testsuite/18_support/96817.cc
+++ b/libstdc++-v3/testsuite/18_support/96817.cc
@@ -24,6 +24,10 @@
 #include <exception>
 #include <stdlib.h>
 
+#ifndef _GLIBCXX_HAVE_LINUX_FUTEX
+# error "This test requries futex support in the library"
+#endif
+
 int init()
 {
 #if __has_include(<sys/single_threaded.h>)
-- 
2.30.2