This is the last PR that's needed (for now) to get libc++'s tests
working with MSVC's STL.
The ADDITIONAL_COMPILE_FLAGS machinery is very useful, but also very
problematic for MSVC, as it doesn't understand most of Clang's compiler
options. We've been dealing with this by simply marking anything that
uses ADDITIONAL_COMPILE_FLAGS as FAIL or SKIPPED, but that creates
significant gaps in test coverage.
Fortunately, ADDITIONAL_COMPILE_FLAGS also supports "features", which
can be slightly enhanced to send Clang-compatible and MSVC-compatible
options to the right compilers.
This patch adds the gcc-style-warnings and cl-style-warnings Lit features,
and uses that to pass the appropriate warning flags to tests. It also uses
TEST_MEOW_DIAGNOSTIC_IGNORED for a few local suppressions of MSVC
warnings.
Found while running libc++'s test suite with MSVC's STL.
* In `escaped_output.unicode.pass.cpp`, replace `_LIBCPP_SHORT_WCHAR`
with `TEST_SHORT_WCHAR`.
+ This was the only test that was directly using the `_LIBCPP` macro.
`libcxx/test/support/test_macros.h` performs this mapping:
c60ac50939/libcxx/test/support/test_macros.h (L442-L444)
* In `msvc_stdlib_force_include.h`, define `TEST_SHORT_WCHAR`.
This makes libc++'s <filesystem> tests compatible with MSVC's STL.
In msvc_stdlib_force_include.h, we need to define 3 more macros:
- _CRT_DECLARE_NONSTDC_NAMES activates the POSIX names of
`getcwd` etc. As the comment explains, we need this because
we test with Clang `-fno-ms-compatibility`, which defines
`__STDC__` to `1`, which causes the UCRT headers to disable
the POSIX names by default.
- Then we need _CRT_NONSTDC_NO_WARNINGS to avoid emitting
deprecation warnings about the POSIX names.
- Finally, we need `NOMINMAX` to seal away the ancient evil.
These macros are documented in https://learn.microsoft.com/en-us/cpp/c-runtime-library/compatibility?view=msvc-170.
As a drive-by change, the patch adds a "simulated" macro for
__has_feature(hwaddress_sanitizer). It also clang-formats all
of msvc_stdlib_force_include.h and removes guards for
__has_builtin(__builtin_source_location) in <source_location>,
since those are not needed anymore.
This is defined both by libcxx/utils/libcxx/test/config.py (for
any windows target) and msvc_stdlib_force_include.h (when testing
specifically the MSVC C++ library).
The command line define (-D_CRT_SECURE_NO_WARNINGS) defines it to the
value 1; change the header define to match that.
Keeping both instances, to keep the fix for cases when not building
in cases that don't use config.py.
Also remove a comment about whether this can be removed; it can't at
least be removed altogether - doing that breaks a number of tests that
otherwise succeed.
Differential Revision: https://reviews.llvm.org/D89588
First, add a TEST_HAS_QUICK_EXIT macro to mirror other C11 features like
TEST_HAS_ALIGNED_ALLOC, and update the tests for that.
Second, get rid of TEST_HAS_C11_FEATURES and _LIBCPP_HAS_C11_FEATURES,
which were only used to ensure that feature macros don't get out of
sync between <__config> and "test_macros.h". This is not necessary
anymore, since we have tests for each individual macro now.
... in `msvc_stdlib_force_include.h` to also ignore new MSVC warning C5215 "'%s' a function parameter with volatile qualified type is deprecated in C++20". Since we're touching it, also update from non-standard `__pragma(meow)` to standard `_Pragma("meow")`.
[libcxx] [test] Calling min and max on an empty valarray is UB.
libcxx/test/std/numerics/numarray/template.valarray/valarray.members/min.pass.cpp
libcxx/test/std/numerics/numarray/template.valarray/valarray.members/max.pass.cpp
The calls `v1.min();` and `v1.max();` were emitting nodiscard warnings
with MSVC's STL. Upon closer inspection, these calls were triggering
undefined behavior. N4842 [valarray.members] says:
"T min() const;
8 Preconditions: size() > 0 is true.
T max() const;
10 Preconditions: size() > 0 is true."
As these tests already provide coverage for non-empty valarrays
(immediately above), I've simply deleted the code for empty valarrays.
[libcxx] [test] Add macros to msvc_stdlib_force_include.h (NFC).
libcxx/test/support/msvc_stdlib_force_include.h
These macros are being used by:
libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/result_of11.pass.cpp
Defining them to nothing allows that test to pass.
[libcxx] [test] Silence MSVC warning C5063 for is_constant_evaluated (NFC).
libcxx/test/std/utilities/meta/meta.const.eval/is_constant_evaluated.pass.cpp
This test is intentionally writing code that MSVC intentionally warns
about, so the warning should be silenced.
Additionally, comment an endif for clarity.
[libcxx] [test] Silence MSVC warning C4127 (NFC).
libcxx/test/support/charconv_test_helpers.h
MSVC avoids emitting this warning when it sees a single constexpr value
being tested, but this condition is a mix of compile-time and run-time.
Using push-disable-pop is the least intrusive way to silence this.
[libcxx] [test] Silence MSVC truncation warning (NFC).
libcxx/test/std/containers/sequences/vector/vector.cons/construct_iter_iter.pass.cpp
This test is intentionally truncating float to int, which MSVC
intentionally warns about, so push-disable-pop is necessary.
[libcxx] [test] Avoid truncation warnings in erase_if tests (NFC).
libcxx/test/std/containers/associative/map/map.erasure/erase_if.pass.cpp
libcxx/test/std/containers/associative/multimap/multimap.erasure/erase_if.pass.cpp
libcxx/test/std/containers/unord/unord.map/erase_if.pass.cpp
libcxx/test/std/containers/unord/unord.multimap/erase_if.pass.cpp
These tests use maps with `short` keys and values, emitting MSVC
truncation warnings from `int`. Adding `static_cast` to `key_type`
and `mapped_type` avoids these warnings.
As these tests require C++20 mode (or newer), for brevity I've changed
the multimap tests to use emplace to initialize the test data.
This has no effect on the erase_if testing.
