libstdc++: testsuite: tolerate non-cancelling sleep

Though sleep, nanosleep and clock_nanosleep are all POSIX cancellation
points, not all target systems follow this POSIX requirement.
30_threads/thread/native_handle/cancel.cc will run until it times out
on such systems.

Rather than failing a C++ library test because of a limitation of the
target system, this patch gives the test a chance to successfully
exercise the features it intends to exercise, by introducing a
cancellation point in a loop that would otherwise run indefinitely on
systems exhibiting this limitation.

for  libstdc++-v3/ChangeLog

	* testsuite/30_threads/thread/native_handle/cancel.cc: Add an
	explicit cancellation point in case sleep_for lacks one.

diff --git a/libstdc++-v3/testsuite/30_threads/thread/native_handle/cancel.cc b/libstdc++-v3/testsuite/30_threads/thread/native_handle/cancel.cc
index dca162b..3cef97e 100644 (file)
--- a/libstdc++-v3/testsuite/30_threads/thread/native_handle/cancel.cc
+++ b/libstdc++-v3/testsuite/30_threads/thread/native_handle/cancel.cc
@@ -30,7 +30,11 @@ void f(std::atomic<bool>& started)
 {
   started = true;
   while (true)
-    std::this_thread::sleep_for(std::chrono::milliseconds(100));
+    {
+      std::this_thread::sleep_for(std::chrono::milliseconds(100));
+      // In case the target system doesn't make sleep a cancellation point...
+      pthread_testcancel();
+    }
 }
 
 int main()