testsuite: Require thread-fence for 29_atomics/atomic_flag/cons/value_init.cc

A recent patch made __atomic_test_and_set no longer fall
back to emitting non-atomic code, but instead will then emit
a call to __atomic_test_and_set, thereby exposing the need
to gate also this test on support for atomics, similar to
r14-3980-g62b29347c38394.

libstdc++-v3:
	* testsuite/29_atomics/atomic_flag/cons/value_init.cc: Add
	dg-require-thread-fence.

diff --git a/libstdc++-v3/testsuite/29_atomics/atomic_flag/cons/value_init.cc b/libstdc++-v3/testsuite/29_atomics/atomic_flag/cons/value_init.cc
index 084e2930f7e25b54fb3acb17a9a59953e4c41df6..f3f38b54dbcdae1db50f6f9657dac767a43f867d 100644 (file)
--- a/libstdc++-v3/testsuite/29_atomics/atomic_flag/cons/value_init.cc
+++ b/libstdc++-v3/testsuite/29_atomics/atomic_flag/cons/value_init.cc
@@ -16,6 +16,7 @@
 // <http://www.gnu.org/licenses/>.
 
 // { dg-do run { target c++20 } }
+// { dg-require-thread-fence "" }
 
 #include <atomic>
 #include <testsuite_hooks.h>