[libcxx-commits] [libcxx] [libc++] Floating Point Atomic (PR #67799)

[Michał Górny via libcxx-commits]

mgorny wrote:

These tests are hanging on my Gentoo amd64 machine:

```
  llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/fetch_add.pass.cpp
  llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/fetch_sub.pass.cpp
  llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/operator.minus_equals.pass.cpp
  llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/operator.plus_equals.pass.cpp
```

I've killed them after they were running at 100% CPU utilization for over 20 minutes.

<details>
<summary>Full output (after killing)</summary>

```
FAIL: llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/operator.minus_equals.pass.cpp (9682 of 9685)
******************** TEST 'llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/operator.minus_equals.pass.cpp' FAILED ********************
Exit Code: 241

Command Output (stdout):
--
# COMPILED WITH
/usr/lib/ccache/bin/x86_64-pc-linux-gnu-clang++ /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/test/std/atomics/atomics.types.generic/atomics.types.float/operator.minus_equals.pass.cpp -pthread --target=x86_64-pc-linux-gnu -nostdinc++ -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/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 -latomic -lc++experimental -nostdlib++ -L /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -Wl,-rpath,/var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -lc++ -o /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/operator.minus_equals.pass.cpp.dir/t.tmp.exe
# executed command: /usr/lib/ccache/bin/x86_64-pc-linux-gnu-clang++ /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/test/std/atomics/atomics.types.generic/atomics.types.float/operator.minus_equals.pass.cpp -pthread --target=x86_64-pc-linux-gnu -nostdinc++ -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/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 -latomic -lc++experimental -nostdlib++ -L /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -Wl,-rpath,/var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -lc++ -o /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/operator.minus_equals.pass.cpp.dir/t.tmp.exe
# EXECUTED AS
/usr/bin/python3.12 /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/utils/run.py --execdir /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/operator.minus_equals.pass.cpp.dir --  /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/operator.minus_equals.pass.cpp.dir/t.tmp.exe
# executed command: /usr/bin/python3.12 /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/utils/run.py --execdir /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/operator.minus_equals.pass.cpp.dir -- /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/operator.minus_equals.pass.cpp.dir/t.tmp.exe
# note: command had no output on stdout or stderr
# error: command failed with exit status: 241

--

********************
FAIL: llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/fetch_sub.pass.cpp (9683 of 9685)
******************** TEST 'llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/fetch_sub.pass.cpp' FAILED ********************
Exit Code: 241

Command Output (stdout):
--
# COMPILED WITH
/usr/lib/ccache/bin/x86_64-pc-linux-gnu-clang++ /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/test/std/atomics/atomics.types.generic/atomics.types.float/fetch_sub.pass.cpp -pthread --target=x86_64-pc-linux-gnu -nostdinc++ -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/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 -latomic -lc++experimental -nostdlib++ -L /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -Wl,-rpath,/var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -lc++ -o /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/fetch_sub.pass.cpp.dir/t.tmp.exe
# executed command: /usr/lib/ccache/bin/x86_64-pc-linux-gnu-clang++ /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/test/std/atomics/atomics.types.generic/atomics.types.float/fetch_sub.pass.cpp -pthread --target=x86_64-pc-linux-gnu -nostdinc++ -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/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 -latomic -lc++experimental -nostdlib++ -L /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -Wl,-rpath,/var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -lc++ -o /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/fetch_sub.pass.cpp.dir/t.tmp.exe
# EXECUTED AS
/usr/bin/python3.12 /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/utils/run.py --execdir /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/fetch_sub.pass.cpp.dir --  /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/fetch_sub.pass.cpp.dir/t.tmp.exe
# executed command: /usr/bin/python3.12 /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/utils/run.py --execdir /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/fetch_sub.pass.cpp.dir -- /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/fetch_sub.pass.cpp.dir/t.tmp.exe
# note: command had no output on stdout or stderr
# error: command failed with exit status: 241

--

********************
FAIL: llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/fetch_add.pass.cpp (9684 of 9685)
******************** TEST 'llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/fetch_add.pass.cpp' FAILED ********************
Exit Code: 241

Command Output (stdout):
--
# COMPILED WITH
/usr/lib/ccache/bin/x86_64-pc-linux-gnu-clang++ /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/test/std/atomics/atomics.types.generic/atomics.types.float/fetch_add.pass.cpp -pthread --target=x86_64-pc-linux-gnu -nostdinc++ -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/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 -latomic -lc++experimental -nostdlib++ -L /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -Wl,-rpath,/var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -lc++ -o /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/fetch_add.pass.cpp.dir/t.tmp.exe
# executed command: /usr/lib/ccache/bin/x86_64-pc-linux-gnu-clang++ /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/test/std/atomics/atomics.types.generic/atomics.types.float/fetch_add.pass.cpp -pthread --target=x86_64-pc-linux-gnu -nostdinc++ -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/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 -latomic -lc++experimental -nostdlib++ -L /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -Wl,-rpath,/var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -lc++ -o /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/fetch_add.pass.cpp.dir/t.tmp.exe
# EXECUTED AS
/usr/bin/python3.12 /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/utils/run.py --execdir /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/fetch_add.pass.cpp.dir --  /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/fetch_add.pass.cpp.dir/t.tmp.exe
# executed command: /usr/bin/python3.12 /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/utils/run.py --execdir /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/fetch_add.pass.cpp.dir -- /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/fetch_add.pass.cpp.dir/t.tmp.exe
# note: command had no output on stdout or stderr
# error: command failed with exit status: 241

--

********************
FAIL: llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/operator.plus_equals.pass.cpp (9685 of 9685)
******************** TEST 'llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/operator.plus_equals.pass.cpp' FAILED ********************
Exit Code: 241

Command Output (stdout):
--
# COMPILED WITH
/usr/lib/ccache/bin/x86_64-pc-linux-gnu-clang++ /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/test/std/atomics/atomics.types.generic/atomics.types.float/operator.plus_equals.pass.cpp -pthread --target=x86_64-pc-linux-gnu -nostdinc++ -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/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 -latomic -lc++experimental -nostdlib++ -L /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -Wl,-rpath,/var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -lc++ -o /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/operator.plus_equals.pass.cpp.dir/t.tmp.exe
# executed command: /usr/lib/ccache/bin/x86_64-pc-linux-gnu-clang++ /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/test/std/atomics/atomics.types.generic/atomics.types.float/operator.plus_equals.pass.cpp -pthread --target=x86_64-pc-linux-gnu -nostdinc++ -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/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 -latomic -lc++experimental -nostdlib++ -L /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -Wl,-rpath,/var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/lib -lc++ -o /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/operator.plus_equals.pass.cpp.dir/t.tmp.exe
# EXECUTED AS
/usr/bin/python3.12 /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/utils/run.py --execdir /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/operator.plus_equals.pass.cpp.dir --  /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/operator.plus_equals.pass.cpp.dir/t.tmp.exe
# executed command: /usr/bin/python3.12 /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/libcxx/utils/run.py --execdir /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/operator.plus_equals.pass.cpp.dir -- /var/tmp/portage/sys-libs/libcxx-18.0.0_pre20231123/work/runtimes_build-abi_x86_64.amd64/test/std/atomics/atomics.types.generic/atomics.types.float/Output/operator.plus_equals.pass.cpp.dir/t.tmp.exe
# note: command had no output on stdout or stderr
# error: command failed with exit status: 241

--

********************
********************
Failed Tests (4):
  llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/fetch_add.pass.cpp
  llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/fetch_sub.pass.cpp
  llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/operator.minus_equals.pass.cpp
  llvm-libc++-shared.cfg.in :: std/atomics/atomics.types.generic/atomics.types.float/operator.plus_equals.pass.cpp


Testing Time: 3378.31s

Total Discovered Tests: 9685
  Unsupported      :  571 (5.90%)
  Passed           : 9069 (93.64%)
  Expectedly Failed:   41 (0.42%)
  Failed           :    4 (0.04%)
```
</details>

https://github.com/llvm/llvm-project/pull/67799