Fixes#75975.
Remove `_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS` for the LLVM 19
release, it was previously marked as deprecated in LLVM 18.
I believe that
`_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_VOID_SPECIALIZATION` was only
used by Google in conjunction with
`_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS`.
Removing both macros together should not cause any issues in practice,
even though we did not announce the removal of
`_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_VOID_SPECIALIZATION` before.
These were disabled due to ODR violations with mixed versions of
clang-tidy and the clang libraries. This issue was fixed in
e19e8600cf743690e1a23fb8a2b0dfbe2dafe559.
This reverts commit 0bbada93a559b604797fe57978f3eca5e41edaeb.
## Abstract
This pull request implements LWG3715: `view_interface::empty` is
overconstrained. Here is an example similar to those described in the
report, which compiles with `-stdlib=libstdc++` but failed to compile
with `-stdlib=libc++`:
```cpp
// https://godbolt.org/z/EWEoTzah3
std::istringstream input("1 2 3 4 5");
auto i = std::views::istream<int>(input);
auto r = std::views::counted(i.begin(), 4) | std::views::take(2);
assert(!r.empty());
```
## Reference
- [Draft C++ Standard:
[view.interface.general]](https://eel.is/c++draft/view.interface.general)
- [LWG3715](https://wg21.link/LWG3715)
This reverts commit 4109b18ee5de1346c2b89a5c89b86bae5c8631d3.
It looks like the automatic detection has false positives. This broke
the following build https://github.com/llvm/llvm-project/pull/85262
On Windows you can not create symlinks without elevated privileges
unless you have Windows developer mode enabled. There's ~67 libcxx tests
that run into failures on windows if your environment is not set up
correctly (Go to windows settings and enable "developer mode").
This change:
- Adds a feature check for whether the host can create symlinks. (see
libcxx/utils/libcxx/test/features.py)
- Mark the feature as required for the 67 tests that hit failures on
windows due to this. This will allow lit to correctly mark these tests
as unsupported instead of unexpectedly failed (this is helpful since
then you know you didn't break something with your change, it's just
that it's not supported with your environment).
When calling setbuf(nullptr, 0) before performing file operations it
should set the file to unbuffered mode. Currently the code avoids
buffering internally, but the underlying stream still can buffer.
This is addressed by disabling the buffering of the underlying stream.
Fixes: https://github.com/llvm/llvm-project/issues/60509
Destroying an ios_base object before it is properly initialized is
undefined behavior. Unlike typical C++ classes the initialization is not
done in the constructor, but in a dedicated init function. Due to
virtual inheritance of the basic_ios object in ostream and friends this
undefined behaviour can be triggered when inheriting from classes that
can throw in their constructor and inheriting from ostream.
Use the __loc_ member of ios_base as sentinel to detect whether the
object has or has not been initialized.
Addresses https://github.com/llvm/llvm-project/issues/57964
Typically the rules in the database are contiguous, but that is not a
requirement. This fixes the case when they are not.
---------
Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
Previously, `__bounded_iter` only checked `operator*`. It allowed the
pointer to go out of bounds with `operator++`, etc., and relied on
`operator*` (which checked `begin <= current < end`) to handle
everything. This has several unfortunate consequences:
First, pointer arithmetic is UB if it goes out of bounds. So by the time
`operator*` checks, it may be too late and the optimizer may have done
something bad. Checking both operations is safer.
Second, `std::copy` and friends currently bypass bounded iterator
checks. I think the only hope we have to fix this is to key on `iter +
n` doing a check. See #78771 for further discussion. Note this PR is not
sufficient to fix this. It adds the output bounds check, but ends up
doing it after the `memmove`, which is too late.
Finally, doing these checks is actually *more* optimizable. See #78829,
which is fixed by this PR. Keeping the iterator always in bounds means
`operator*` can rely on some invariants and only needs to check `current
!= end`. This aligns better with common iterator patterns, which use
`!=` instead of `<`, so it's easier to delete checks with local
reasoning.
See https://godbolt.org/z/vEWrWEf8h for how this new `__bounded_iter`
impacts compiler output. The old `__bounded_iter` injected checks inside
the loops for all the `sum()` functions, which not only added a check
inside a loop, but also impeded Clang's vectorization. The new
`__bounded_iter` allows all the checks to be optimized out and we emit
the same code as if it wasn't here.
Not everything is ideal however. `add_and_deref` ends up emitting two
comparisons now instead of one. This is because a missed optimization in
Clang. I've filed #78875 for that. I suspect (with no data) that this PR
is still a net performance win because impeding ranged-for loops is
particularly egregious. But ideally we'd fix the optimizer and make
`add_and_deref` fine too.
There's also something funny going on with `std::ranges::find` which I
have not yet figured out yet, but I suspect there are some further
missed optimization opportunities.
Fixes#78829.
(CC @danakj)
These are simply null checks, so use `_LIBCPP_ASSERT_NON_NULL`. This
allows us to restore a bunch of the old debug tests. I've extended them
to also cover the const iterators, as those run through different
codepaths than the const ones.
This does the easier (and less important) half of #80212.
This reverts commit aa60b2687, which was a temporary workaround.
The underlying issue was fixed in Clang via c2c840bd92cf.
This was originally https://reviews.llvm.org/D158694.
The `128-bit-atomics` libcxx feature is incorrectly named because tests
that are Xfailed with it is really using `int[128]`. Additionally,
because toolchain support for that feature is determined based on a much
smaller size (`char[16]`), tests would execute incorrectly without
required toolchain support.
So, rename `128-bit-atomics` as `1024-bit-atomics`, and use an
appropriate type to check for the presence of the feature.
The `parse.pass.cpp` tests doen't need to call
`test_format_context_create` to create a `basic_format_context`, so they
shouldn't include `test_format_context.h`.
The `to_address` mechanism works around the iterator debugging
mechanisms of MSVC STL. Related to
[LWG3989](https://cplusplus.github.io/LWG/issue3989).
Discovered when implementing `formatter<tuple>` in MSVC STL. With the
inclusion removed, `std/utilities/format/format.tuple/parse.pass.cpp`
when using enhanced MSVC STL (and `/utf-8` option for MSVC).
The current selection is done in the test scripts which gives the user
no control where to find clang-tidy. The version selection itself is
hard-coded and not based on the version of clang used.
This moves the selection to configuration time and tries to find a
better match.
- Mixing the version of clang-tidy and the clang libraries causes ODR
violations. This results in practice in crashes or incorrect results.
- Mixing the version of clang-tidy and the clang binary sometimes causes
issues with supported diagnostic flags. For example, flags tested
against clang 17 may not be available in clang-tidy 16.
Currently clang-tidy 18.1 can be used, it tests against the clang
libraries version 18. This is caused by the new LLVM version numbering
scheme.
The new selection tries to match the clang version or the version of the
HEAD and the last 3 releases. (During the release period libc++ supports
4 versions instead of the typical 3 versions.)
This fixes MSVC warning C4127: conditional expression is constant.
Testing `TEST_STD_AT_LEAST_20_OR_RUNTIME_EVALUATED` by itself doesn't
emit this warning, but the condition here is more complicated. I'm
expanding the macro and mechanically simplifying the resulting code.
(Yeah, this warning is often annoying, and I introduced
`TEST_STD_AT_LEAST_20_OR_RUNTIME_EVALUATED` to avoid this warning
elsewhere, so it's disappointing that it doesn't make the compiler happy
here. If this change is undesirable, I can replace it with
`ADDITIONAL_COMPILE_FLAGS(cl-style-warnings)`, but ideally I'd like to
avoid having to suppress it.)
---------
Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
LIT was never really meant to generate tests during discovery,
and we probably shouldn't be doing this.
This hack is even worse than the initial attempt because it buries the
"UNSUPPORTED" at the bottom of the test.
Those have been crippling the CI for over a week now. This is the only
solution I see until we gain a better understanding of why they fail.
Otherwise all other patches are blocked on these spurious failures in
the stage1 of the CI.
__has_extension(...) doesn't work as intended when -pedantic-errors is
used with Clang. With that flag, __has_extension(...) is equivalent to
__has_feature(...), which means that checks like
__has_extension(pragma_clang_attribute_external_declaration)
will return 0. In turn, this has the effect of disabling availability
markup in libc++, which is undesirable.
rdar://124078119
When echo is used for piping, lit uses the system echo rather than the
builtin echo. The system echo on AIX doesn't support the `-n` option,
which causes these tests to fail. Use input redirection, so the builtin
echo can be used.
An immediate colon signifeis that the range-format-spec contains only
range-underlying-spec.
This patch allows this code to compile and run:
```c++
std::println("{::<<9?}", std::span<const char>{"Hello", sizeof "Hello"});
```
We forward declare `reference_wrapper` in multiple places already. This
moves the declaration to the canonical place and removes unnecessary
includes of `__functional/reference_wrapper.h`.
Originally, we used __libcpp_verbose_abort to handle assertion failures.
That function was declared from all public headers. Since we don't use
that mechanism anymore, we don't need to declare __libcpp_verbose_abort
from all public headers, and we can clean up a lot of unnecessary
includes.
This patch also moves the definition of the various assertion categories
to the <__assert> header, since we now rely on regular IWYU for these
assertion macros.
rdar://105510916
Picolibc does not provide the clock_gettime function nor the "rt" library.
check_library_exists was invalidly detecting the "rt" library due to cmake issue
present, when cross-compiling[1]. This resulted with "chrono.cpp" trying to link
to the "rt" library and following error:
unable to find library from dependent library specifier: rt
[1] https://gitlab.kitware.com/cmake/cmake/-/issues/18121
