[libcxx-commits] [libcxx] [libc++][TZDB] Implements time_zone get_info(local_time). (PR #89537)

[via libcxx-commits]

zeroomega wrote:

We started to see flakiness in test `llvm-libc++-static.cfg.in :: std/time/time.zone/time.zone.timezone/time.zone.members/get_info.local_time.pass.cpp` in libcxx testing on linux-x64, after this change was landed

```
Exit Code: 250

Command Output (stdout):
--
# COMPILED WITH
/b/s/w/ir/x/w/llvm_build/./bin/clang++ /b/s/w/ir/x/w/llvm-llvm-project/libcxx/test/std/time/time.zone/time.zone.timezone/time.zone.members/get_info.local_time.pass.cpp -pthread --target=x86_64-unknown-linux-gnu -nostdinc++ -I /b/s/w/ir/x/w/llvm_build/include/c++/v1 -I /b/s/w/ir/x/w/llvm_build/include/x86_64-unknown-linux-gnu/c++/v1 -I /b/s/w/ir/x/w/llvm-llvm-project/libcxx/test/support -std=c++26 -Werror -Wall -Wctad-maybe-unsupported -Wextra -Wshadow -Wundef -Wunused-template -Wno-unused-command-line-argument -Wno-attributes -Wno-pessimizing-move -Wno-noexcept-type -Wno-atomic-alignment -Wno-reserved-module-identifier -Wdeprecated-copy -Wdeprecated-copy-dtor -Wno-user-defined-literals -Wno-tautological-compare -Wsign-compare -Wunused-variable -Wunused-parameter -Wunreachable-code -Wno-unused-local-typedef -Wno-local-type-template-args -Wno-c++11-extensions -Wno-unknown-pragmas -Wno-pass-failed -Wno-mismatched-new-delete -Wno-redundant-move -Wno-self-move -D_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER -D_LIBCPP_ENABLE_EXPERIMENTAL -D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_NONE -Werror=thread-safety -Wuser-defined-warnings  -lc++experimental -nostdlib++ -L /b/s/w/ir/x/w/llvm_build/./lib/x86_64-unknown-linux-gnu -lc++ -lc++abi -o /b/s/w/ir/x/w/llvm_build/runtimes/runtimes-x86_64-unknown-linux-gnu-bins/test/std/time/time.zone/time.zone.timezone/time.zone.members/Output/get_info.local_time.pass.cpp.dir/t.tmp.exe
# executed command: /b/s/w/ir/x/w/llvm_build/./bin/clang++ /b/s/w/ir/x/w/llvm-llvm-project/libcxx/test/std/time/time.zone/time.zone.timezone/time.zone.members/get_info.local_time.pass.cpp -pthread --target=x86_64-unknown-linux-gnu -nostdinc++ -I /b/s/w/ir/x/w/llvm_build/include/c++/v1 -I /b/s/w/ir/x/w/llvm_build/include/x86_64-unknown-linux-gnu/c++/v1 -I /b/s/w/ir/x/w/llvm-llvm-project/libcxx/test/support -std=c++26 -Werror -Wall -Wctad-maybe-unsupported -Wextra -Wshadow -Wundef -Wunused-template -Wno-unused-command-line-argument -Wno-attributes -Wno-pessimizing-move -Wno-noexcept-type -Wno-atomic-alignment -Wno-reserved-module-identifier -Wdeprecated-copy -Wdeprecated-copy-dtor -Wno-user-defined-literals -Wno-tautological-compare -Wsign-compare -Wunused-variable -Wunused-parameter -Wunreachable-code -Wno-unused-local-typedef -Wno-local-type-template-args -Wno-c++11-extensions -Wno-unknown-pragmas -Wno-pass-failed -Wno-mismatched-new-delete -Wno-redundant-move -Wno-self-move -D_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER -D_LIBCPP_ENABLE_EXPERIMENTAL -D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_NONE -Werror=thread-safety -Wuser-defined-warnings -lc++experimental -nostdlib++ -L /b/s/w/ir/x/w/llvm_build/./lib/x86_64-unknown-linux-gnu -lc++ -lc++abi -o /b/s/w/ir/x/w/llvm_build/runtimes/runtimes-x86_64-unknown-linux-gnu-bins/test/std/time/time.zone/time.zone.timezone/time.zone.members/Output/get_info.local_time.pass.cpp.dir/t.tmp.exe
# EXECUTED AS
/b/s/w/ir/cipd_bin_packages/cpython3/bin/python3.8 /b/s/w/ir/x/w/llvm-llvm-project/libcxx/utils/run.py --execdir /b/s/w/ir/x/w/llvm_build/runtimes/runtimes-x86_64-unknown-linux-gnu-bins/test/std/time/time.zone/time.zone.timezone/time.zone.members/Output/get_info.local_time.pass.cpp.dir --  /b/s/w/ir/x/w/llvm_build/runtimes/runtimes-x86_64-unknown-linux-gnu-bins/test/std/time/time.zone/time.zone.timezone/time.zone.members/Output/get_info.local_time.pass.cpp.dir/t.tmp.exe
# executed command: /b/s/w/ir/cipd_bin_packages/cpython3/bin/python3.8 /b/s/w/ir/x/w/llvm-llvm-project/libcxx/utils/run.py --execdir /b/s/w/ir/x/w/llvm_build/runtimes/runtimes-x86_64-unknown-linux-gnu-bins/test/std/time/time.zone/time.zone.timezone/time.zone.members/Output/get_info.local_time.pass.cpp.dir -- /b/s/w/ir/x/w/llvm_build/runtimes/runtimes-x86_64-unknown-linux-gnu-bins/test/std/time/time.zone/time.zone.timezone/time.zone.members/Output/get_info.local_time.pass.cpp.dir/t.tmp.exe
# .---command stderr------------
# | Assertion failure: lhs.end == rhs.end /b/s/w/ir/x/w/llvm-llvm-project/libcxx/test/std/time/time.zone/time.zone.timezone/time.zone.members/get_info.local_time.pass.cpp 77
# | 
# | End:
# | Expected output 1880-08-02 00:25:21
# | Actual output   1880-08-02 00:25:00
# `-----------------------------
# error: command failed with exit status: 250
```

Failed build task: https://ci.chromium.org/ui/p/fuchsia/builders/toolchain.ci/clang-linux-x64/b8745592240286102897/overview

This test fails about 1 in 3 runs, randomly after this PR was landed. 
Could you take a look please?


https://github.com/llvm/llvm-project/pull/89537