From: Jonathan Wakely Date: Wed, 20 Oct 2021 19:12:28 +0000 (+0100) Subject: libstdc++: Add missing test for std::optional::transform(F&&) X-Git-Tag: basepoints/gcc-13~3731 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=4ba4b053151a20262d4b61eb4501aa1c48337abb;p=thirdparty%2Fgcc.git libstdc++: Add missing test for std::optional::transform(F&&) The test_copy_elision() function was supposed to ensure that the result is constructed directly in the std::optional, without early temporary materialization. But I forgot to write the test. libstdc++-v3/ChangeLog: * testsuite/20_util/optional/monadic/transform.cc: Check that an rvalue result is not materialized too soon. --- diff --git a/libstdc++-v3/testsuite/20_util/optional/monadic/transform.cc b/libstdc++-v3/testsuite/20_util/optional/monadic/transform.cc index d01ccb2e0f23..13977b8ba8d4 100644 --- a/libstdc++-v3/testsuite/20_util/optional/monadic/transform.cc +++ b/libstdc++-v3/testsuite/20_util/optional/monadic/transform.cc @@ -110,6 +110,23 @@ static_assert( test_forwarding() ); constexpr bool test_copy_elision() { + struct immovable + { + constexpr immovable(int p) : power_level(p) { } + immovable(immovable&&) = delete; + + int power_level; + }; + + struct Force + { + constexpr immovable operator()(int i) const { return {i+1}; } + }; + + std::optional irresistible(9000); + std::optional object = irresistible.transform(Force{}); + VERIFY( object->power_level > 9000 ); + return true; }