From fba15da8fa518bfb8d3e061795bc3ca2dea01d27 Mon Sep 17 00:00:00 2001 From: Jonathan Wakely Date: Sun, 21 Jan 2024 18:11:16 +0000 Subject: libstdc++: Fix std::chrono::file_clock conversions for low-precision times THe std::chrono::file_clock conversions were not using common_type and so failed to compile when converting anything that should have increased precision after arithmetic with a std::chrono::seconds value. libstdc++-v3/ChangeLog: * include/bits/chrono.h (__file_clock::from_sys) (__file_clock::to_sys, __file_clock::_S_from_sys) (__file_clock::_S_to_sys): Use common_type for return type. * testsuite/std/time/clock/file/members.cc: Check round trip conversion for time with lower precision that seconds. --- libstdc++-v3/include/bits/chrono.h | 14 ++++++++------ libstdc++-v3/testsuite/std/time/clock/file/members.cc | 9 +++++++++ 2 files changed, 17 insertions(+), 6 deletions(-) diff --git a/libstdc++-v3/include/bits/chrono.h b/libstdc++-v3/include/bits/chrono.h index 6f4fe55..0773867 100644 --- a/libstdc++-v3/include/bits/chrono.h +++ b/libstdc++-v3/include/bits/chrono.h @@ -1453,14 +1453,14 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2) #if __cplusplus > 201703L template static - chrono::file_time<_Dur> + chrono::file_time> from_sys(const chrono::sys_time<_Dur>& __t) noexcept { return _S_from_sys(__t); } // For internal use only template static - chrono::sys_time<_Dur> + chrono::sys_time> to_sys(const chrono::file_time<_Dur>& __t) noexcept { return _S_to_sys(__t); } #endif // C++20 @@ -1477,20 +1477,22 @@ _GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2) // For internal use only template static - chrono::time_point<__file_clock, _Dur> + chrono::time_point<__file_clock, common_type_t<_Dur, chrono::seconds>> _S_from_sys(const chrono::time_point<__sys_clock, _Dur>& __t) noexcept { - using __file_time = chrono::time_point<__file_clock, _Dur>; + using _CDur = common_type_t<_Dur, chrono::seconds>; + using __file_time = chrono::time_point<__file_clock, _CDur>; return __file_time{__t.time_since_epoch()} - _S_epoch_diff; } // For internal use only template static - chrono::time_point<__sys_clock, _Dur> + chrono::time_point<__sys_clock, common_type_t<_Dur, chrono::seconds>> _S_to_sys(const chrono::time_point<__file_clock, _Dur>& __t) noexcept { - using __sys_time = chrono::time_point<__sys_clock, _Dur>; + using _CDur = common_type_t<_Dur, chrono::seconds>; + using __sys_time = chrono::time_point<__sys_clock, _CDur>; return __sys_time{__t.time_since_epoch()} + _S_epoch_diff; } }; diff --git a/libstdc++-v3/testsuite/std/time/clock/file/members.cc b/libstdc++-v3/testsuite/std/time/clock/file/members.cc index 54459cc..9d217b1 100644 --- a/libstdc++-v3/testsuite/std/time/clock/file/members.cc +++ b/libstdc++-v3/testsuite/std/time/clock/file/members.cc @@ -41,9 +41,18 @@ test02() VERIFY( t - s < 1s ); } +void +test03() +{ + using namespace std::chrono; + auto st = sys_days(2024y/January/21); + VERIFY( file_clock::to_sys(file_clock::from_sys(st)) == st ); +} + int main() { test01(); test02(); + test03(); } -- cgit v1.1