https://gcc.gnu.org/g:06ac4cff18a176cc25e485534b4954f26ad0a918
commit r14-12595-g06ac4cff18a176cc25e485534b4954f26ad0a918 Author: Jonathan Wakely <[email protected]> Date: Thu May 15 19:32:01 2025 +0100 libstdc++: Fix std::format of chrono::local_days with {} [PR120293] Formatting of chrono::local_days with an empty chrono-specs should be equivalent to inserting it into an ostream, which should use the overload for inserting chrono::sys_days into an ostream. The implementation of empty chrono-specs in _M_format_to_ostream takes some short cuts, and that wasn't being done correctly for chrono::local_days. libstdc++-v3/ChangeLog: PR libstdc++/120293 * include/bits/chrono_io.h (_M_format_to_ostream): Add special case for local_time convertible to local_days. * testsuite/std/time/clock/local/io.cc: Check formatting of chrono::local_days. Reviewed-by: Tomasz Kamiński <[email protected]> (cherry picked from commit 1ed7585bf60ba9940ca5dc6d2c72dba86eea7b4d) Diff: --- libstdc++-v3/include/bits/chrono_io.h | 3 +++ libstdc++-v3/testsuite/std/time/clock/local/io.cc | 3 +++ 2 files changed, 6 insertions(+) diff --git a/libstdc++-v3/include/bits/chrono_io.h b/libstdc++-v3/include/bits/chrono_io.h index 0fc5013e0daa..6b3f361f8294 100644 --- a/libstdc++-v3/include/bits/chrono_io.h +++ b/libstdc++-v3/include/bits/chrono_io.h @@ -733,6 +733,9 @@ namespace __format // sys_time with period greater or equal to days: if constexpr (is_convertible_v<_Tp, chrono::sys_days>) __os << _S_date(__t); + // Or a local_time with period greater or equal to days: + else if constexpr (is_convertible_v<_Tp, chrono::local_days>) + __os << _S_date(__t); else // Or it's formatted as "{:L%F %T}": { auto __days = chrono::floor<chrono::days>(__t); diff --git a/libstdc++-v3/testsuite/std/time/clock/local/io.cc b/libstdc++-v3/testsuite/std/time/clock/local/io.cc index b4d562f36d12..67818e876497 100644 --- a/libstdc++-v3/testsuite/std/time/clock/local/io.cc +++ b/libstdc++-v3/testsuite/std/time/clock/local/io.cc @@ -89,6 +89,9 @@ test_format() s = std::format("{}", local_seconds{}); VERIFY( s == "1970-01-01 00:00:00" ); + + s = std::format("{}", local_days{}); // PR libstdc++/120293 + VERIFY( s == "1970-01-01" ); } void
