[PATCHv3 1/6] Improve libstdc++-v3 async test

[Jonathan Wakely]

On 01/08/18 14:19 +0100, Mike Crowe wrote:
>Add tests for waiting for the future using both std::chrono::steady_clock
>and std::chrono::system_clock in preparation for dealing with those clocks
>properly in futex.cc.
>---
> libstdc++-v3/testsuite/30_threads/async/async.cc | 33 ++++++++++++++++++++++++
> 1 file changed, 33 insertions(+)
>
>diff --git a/libstdc++-v3/testsuite/30_threads/async/async.cc b/libstdc++-v3/testsuite/30_threads/async/async.cc
>index 4c2cdd1a534..015bcce0c2c 100644
>--- a/libstdc++-v3/testsuite/30_threads/async/async.cc
>+++ b/libstdc++-v3/testsuite/30_threads/async/async.cc
>@@ -51,17 +51,50 @@ void test02()
>   VERIFY( status == std::future_status::timeout );
>   status = f1.wait_until(std::chrono::system_clock::now());
>   VERIFY( status == std::future_status::timeout );
>+  status = f1.wait_until(std::chrono::steady_clock::now());
>+  VERIFY( status == std::future_status::timeout );
>   l.unlock();  // allow async thread to proceed
>   f1.wait();   // wait for it to finish
>   status = f1.wait_for(std::chrono::milliseconds(0));
>   VERIFY( status == std::future_status::ready );
>   status = f1.wait_until(std::chrono::system_clock::now());
>   VERIFY( status == std::future_status::ready );
>+  status = f1.wait_until(std::chrono::steady_clock::now());
>+  VERIFY( status == std::future_status::ready );
>+}
>+
>+// This test is prone to failures if run on a loaded machine where the
>+// kernel decides not to schedule us for several seconds. It also
>+// assumes that no-one will warp CLOCK whilst the test is
>+// running.
>+template<typename CLOCK>
>+void test03()
>+{
>+  auto const start = CLOCK::now();
>+  future<void> f1 = async(launch::async, []() {
>+      std::this_thread::sleep_for(std::chrono::seconds(2));

Thanks for reducing these times since the last patch. I think this
test improvement can go on trunk, and if we see too many failures we
can adjust the times.