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Differential D29139

[libcxx] [test] Fix Clang -Wpessimizing-move "moving a temporary object prevents copy elision".
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Authored by STL_MSFT on Jan 25 2017, 10:37 AM.

Details

Reviewers
mclow.lists
EricWF
Summary

[libcxx] [test] Fix Clang -Wpessimizing-move "moving a temporary object prevents copy elision".

N4618 30.6.6 [futures.unique_future]/12 declares "shared_future<R> share() noexcept;".

Diff Detail

Event Timeline

STL_MSFT created this revision.Jan 25 2017, 10:37 AM
Herald edited edge metadata. · View Herald TranscriptJan 25 2017, 10:37 AM
EricWF accepted this revision.Feb 4 2017, 2:56 PM
This revision is now accepted and ready to land.Feb 4 2017, 2:56 PM
STL_MSFT mentioned this in rL294158: [libcxx] [test] Fix Clang -Wpessimizing-move "moving a temporary object….Feb 5 2017, 2:59 PM
STL_MSFT closed this revision.Feb 5 2017, 3:05 PM

Revision Contents

PathSize
test/
std/
thread/
futures/
futures.unique_future/
12 lines

Diff 85781

test/std/thread/futures/futures.unique_future/share.pass.cpp

Show All 20 Lines
int main() int main()
{ {
{ {
typedef int T; typedef int T;
std::promise<T> p; std::promise<T> p;
std::future<T> f0 = p.get_future(); std::future<T> f0 = p.get_future();
static_assert( noexcept(f0.share()), ""); static_assert( noexcept(f0.share()), "");
std::shared_future<T> f = std::move(f0.share()); std::shared_future<T> f = f0.share();
assert(!f0.valid()); assert(!f0.valid());
assert(f.valid()); assert(f.valid());
} }
{ {
typedef int T; typedef int T;
std::future<T> f0; std::future<T> f0;
static_assert( noexcept(f0.share()), ""); static_assert( noexcept(f0.share()), "");
std::shared_future<T> f = std::move(f0.share()); std::shared_future<T> f = f0.share();
assert(!f0.valid()); assert(!f0.valid());
assert(!f.valid()); assert(!f.valid());
} }
{ {
typedef int& T; typedef int& T;
std::promise<T> p; std::promise<T> p;
std::future<T> f0 = p.get_future(); std::future<T> f0 = p.get_future();
static_assert( noexcept(f0.share()), ""); static_assert( noexcept(f0.share()), "");
std::shared_future<T> f = std::move(f0.share()); std::shared_future<T> f = f0.share();
assert(!f0.valid()); assert(!f0.valid());
assert(f.valid()); assert(f.valid());
} }
{ {
typedef int& T; typedef int& T;
std::future<T> f0; std::future<T> f0;
static_assert( noexcept(f0.share()), ""); static_assert( noexcept(f0.share()), "");
std::shared_future<T> f = std::move(f0.share()); std::shared_future<T> f = f0.share();
assert(!f0.valid()); assert(!f0.valid());
assert(!f.valid()); assert(!f.valid());
} }
{ {
typedef void T; typedef void T;
std::promise<T> p; std::promise<T> p;
std::future<T> f0 = p.get_future(); std::future<T> f0 = p.get_future();
static_assert( noexcept(f0.share()), ""); static_assert( noexcept(f0.share()), "");
std::shared_future<T> f = std::move(f0.share()); std::shared_future<T> f = f0.share();
assert(!f0.valid()); assert(!f0.valid());
assert(f.valid()); assert(f.valid());
} }
{ {
typedef void T; typedef void T;
std::future<T> f0; std::future<T> f0;
static_assert( noexcept(f0.share()), ""); static_assert( noexcept(f0.share()), "");
std::shared_future<T> f = std::move(f0.share()); std::shared_future<T> f = f0.share();
assert(!f0.valid()); assert(!f0.valid());
assert(!f.valid()); assert(!f.valid());
} }
} }