The output of
template<class charT, class traits>
basic_ostream<charT, traits>&
operator<<(basic_ostream<charT, traits>& out, thread::id id);
is affected by the state of out. The wording states
[thread.thread.id]/2
The text representation for the character type charT of an object of
type thread::id is an unspecified sequence of charT such that, for two
objects of type thread::id x and y, if x == y is true, the thread::id
objects have the same text representation, and if x != y is true, the
thread::id objects have distinct text representations.
[thread.thread.id]/9
template<class charT, class traits>
basic_ostream<charT, traits>&
operator<< (basic_ostream<charT, traits>& out, thread::id id);
Effects: Inserts the text representation for charT of id into out.
This wording changed in C++23 due to adding a formatter specialization for
thread::id. However the requirement was the same in older versions of C++.
This issue is that thread::id is an integral or pointer and affected by the
formatting manipulators for them. Thus the text representation can differ if
x == y which violates the requirements.
The fix has to hard-code some formatting style for the text
representation. It uses the Standard specified default values
Table 124: basic_ios::init() effects [tab:basic.ios.cons] flags()
flags() skipws | dec
Fixes PR: https://llvm.org/PR62073
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D153336
Currently, there are no tests to confirm without a doubt the constructor of latch is really constexpr and explicit.
I think this would be an addition that it would not harm to have. In another revision, I was asked to add tests for an almost identical case which made me consider adding this test for the latch class too.
Reviewed By: #libc, philnik
Spies: philnik, libcxx-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D154957
If I read the standard correctly, the public constructor of "barrier" should be marked as "constexpr explicit".
I see some of the internal classes used by the barrier header are correctly marked but I think, if I'm not mistaken, the standard would like the public class to have the correct definition as well.
Because the implementation that llvm uses by default is not constexpr friendly at this time, this revision will focus on only marking it as explicit.
Reviewed By: #libc, philnik, Mordante
Spies: philnik, Mordante, libcxx-commits
Differential Revision: https://reviews.llvm.org/D154590
This makes <__threading_support> closer to handling only the bridge
between the system's implementation of threading and the rest of libc++.
Differential Revision: https://reviews.llvm.org/D154464
There are discussions about different ways of implementing `stop_token` to make it more performant
mark `stop_token` as experimental to allow us to change the design before it is shipped
Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
Differential Revision: https://reviews.llvm.org/D154700
I made sure they all had some expected-error output in them. Many of
these tests would be better implemented as a positive test using SFINAE,
but this is beyond the scope of this patch.
Differential Revision: https://reviews.llvm.org/D153980
Those were found while trying to enable configurations like no-threads
and no-localization with Clang modules enabled.
Differential Revision: https://reviews.llvm.org/D153977
A few tests were also straightforward to translate to SFINAE tests
instead, so in a few cases I did that and removed the .fail.cpp test
entirely.
Differential Revision: https://reviews.llvm.org/D153149
Some tests in our test suite are unbelievably slow on GCC due to the
use of the always_inline attribute. See [1] for more details.
This patch introduces the GCC-ALWAYS_INLINE-FIXME lit feature to
disable tests that are plagued by that issue. At the same time, it
moves several existing tests from ad-hoc `UNSUPPORTED: gcc-12` markup
to the new GCC-ALWAYS_INLINE-FIXME feature, and marks the slowest tests
reported by the CI as `UNSUPPORTED: GCC-ALWAYS_INLINE-FIXME`.
[1]: https://discourse.llvm.org/t/rfc-stop-supporting-extern-instantiations-with-gcc/71277/1
Differential Revision: https://reviews.llvm.org/D152736
The code has been quite ready for a while now and there are no more ABI
breaking papers. So this is a good time to mark the feature as stable.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D150802
Like done D149543 this validates the other formatter specializations.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D150041
This is based on the last open review comment in D144331 and is applied
to all occurrences.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D147885
This file was added before we started granularizing the headers, but is essentially just a granularized header. This moves the header to the correct place.
Reviewed By: #libc, EricWF
Spies: libcxx-commits, arichardson, mikhail.ramalho
Differential Revision: https://reviews.llvm.org/D146395
Since stacktrace header is WIP and it's not sure that will be done
before LLVM17 update the documentation. When the header is implemented
implementing the formatter is trivial, so that can be done quickly
afterwards.
Implements parts of:
- P2693R1 Formatting thread::id and stacktrace
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D144331
The use_system_cxx_lib Lit feature was only used for back-deployment
testing. However, one immense hole in that setup was that we didn't
have a proper way to test Apple's own libc++ outside of back-deployment,
which was embodied by the fact that we needed to define _LIBCPP_DISABLE_AVAILABILITY
when testing (see change in libcxx/utils/libcxx/test/params.py).
This led to the apple-system testing configuration not checking for
availability markup, which is obviously quite bad since the library
we ship actually has availability markup.
Using stdlib=<VENDOR>-libc++ instead to encode back-deployment restrictions
on tests is simpler and it makes it possible to naturally support tests
such as availability markup checking even in the tip-of-trunk Apple-libc++
configuration.
Differential Revision: https://reviews.llvm.org/D146366
Instead of writing something like `XFAIL: use_system_cxx_lib && target=...`
to XFAIL back-deployment tests, introduce named Lit features like
`availability-shared_mutex-missing` to represent those. This makes the
XFAIL annotations leaner, and solves the problem of XFAIL comments
potentially getting out of sync. This would also make it easier for
another vendor to add their own annotations to the test suite by simply
changing how the feature is defined for their OS releases, instead
of having to modify hundreds of tests to add repetitive annotations.
This doesn't touch *all* annotations -- only annotations that were widely
duplicated are given named features (e.g. when filesystem or shared_mutex
were introduced). I still think it probably doesn't make sense to have a
named feature for every single fix we make to the dylib.
This is in essence a revert of 2659663, but since then the test suite
has changed significantly. Back when I did 2659663, the configuration
files we have for the test suite right now were being bootstrapped and
it wasn't clear how to provide these features for back-deployment in
that context. Since then, we have a streamlined way of defining these
features in `features.py` and that doesn't impact the ability for a
configuration file to stay minimal.
The original motivation for this change was that I am about to propose
a change that would touch essentially all XFAIL annotations for back-deployment
in the test suite, and this greatly reduces the number of lines changed
by that upcoming change, in addition to making the test suite generally
better.
Differential Revision: https://reviews.llvm.org/D146359
This also updates the moved code to the current style. (i.e. `_VSTD` -> `std`, `_LIBCPP_INLINE_VISIBILITY` -> `_LIBCPP_HIDE_FROM_ABI`, clang-format).
Reviewed By: Mordante, #libc, EricWF
Spies: arichardson, libcxx-commits, mikhail.ramalho
Differential Revision: https://reviews.llvm.org/D146228
This has been done using the following commands
find libcxx/test -type f -exec perl -pi -e 's|^([^/]+?)((?<!::)ptrdiff_t)|\1std::\2|' \{} \;
find libcxx/test -type f -exec perl -pi -e 's|^([^/]+?)((?<!::)max_align_t)|\1std::\2|' \{} \;
The std module doesn't export declarations in the global namespaace.,
This is a preparation for that module.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D146550
As explained in the release note, libc++ used to provide various
global variables as an extension in C++03 mode. Unfortunately, that
made our definition non-conforming in all standard modes. This was
never a big problem until recently, since we are trying to support
C++20 Modules in libc++, and that requires cleaning up the definition
of these variables.
This change is the first in a series of changes to achieve our end goal.
This patch removes the ability for users to rely on the (incorrect)
definition of those global variables inside the shared library. The
plan is to then remove those definitions from the shared library
(which is an ABI break but I don't think it will have impact), and
finally to make our definition of those variables conforming in all
standard modes.
Differential Revision: https://reviews.llvm.org/D145422
We pretty consistently don't define those cause they are not needed,
and it removes the potential pitfall to think that these tests are
being run. This doesn't touch .compile.fail.cpp tests since those
should be replaced by .verify.cpp tests anyway, and there would be
a lot to fix up.
As a fly-by, I also fixed a bit of formatting, removed a few unused
includes and made some very minor, clearly NFC refactorings such as
in allocator.traits/allocator.traits.members/allocate.verify.cpp where
the old test basically made no sense the way it was written.
Differential Revision: https://reviews.llvm.org/D146236
While investigating the flaky tests on the mac backdeployment targets
it seems the tests are different than suggested in the LWG issue.
That tests "does work", grabs the mutex, marks the task as done, and
finally calls the notifier.
Our test emulated "does work" after the notification, effectively
sleeping with a lock held. This has been fixed.
A second improvement is that the test fails when, due to OS
scheduling, the condition variable is not used in the main thread.
During discussing the approach of the patch with @ldionne, he
noticed the real reason why the test is flaky; the Apple
backdeployment targets use a dylib, which does not contain the
fix. So the test can't be tested on that platform; it only
proves the LWG issue was correct and the Standard contained
a bug.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D143816
Releasing the mutex before the call to notify_all is an optimization.
This optimization cannot be used here. The thread waiting on the
condition might destroy the associated resources — mutex + condition
variable — and the notifier thread will access an destroyed variable
— the condition variable. In fact, notify_all_at_thread_exit is meant
exactly to join on detached threads, and the waiting thread doesn't
expect for the notifier thread to access any further shared resources,
making this scenario very likely to happen. The waiting thread might
awake spuriously on the release of the mutex lock. The reorder is
necessary to prevent this race.
Further details can be found at https://cplusplus.github.io/LWG/issue3343.
Differential Revision: https://reviews.llvm.org/D105758
There are a handful of standard library types that are intended
to support CTAD but don't need any explicit deduction guides to
do so.
This patch adds a dummy deduction guide to those types to suppress
-Wctad-maybe-unsupported (which gets emitted in user code).
This is a re-application of the original patch by Eric Fiselier in
fcd549a7d8 which had been reverted due to reasons lost at this point.
I also added the macro to a few more types. Reviving this patch was
prompted by the discussion on https://llvm.org/D133425.
Differential Revision: https://reviews.llvm.org/D133535
Increase the timeout tolerance if TEST_IS_EXECUTED_IN_A_SLOW_ENVIRONMENT
is set, similarly to how it's done in a couple other tests.
Use `std::this_thread::yield();` instead of busylooping. When multiple
threads are busylooping, it's plausible that not all threads even get
started running before the timeout runs out.
This makes the threading tests succeed if run in Windows runners on
Github Actions.
Differential Revision: https://reviews.llvm.org/D131483
This makes its role clearer. It's plausible that one may want to manually
define TEST_IS_EXECUTED_IN_A_SLOW_ENVIRONMENT when running the tests in
some environments - in particular, it seems to be necessary to use the
higher tolerance timeouts if running the tests on Windows runners
on Github Actions.
Also add the descriptive comment in one file where it was missing.
Differential Revision: https://reviews.llvm.org/D131484
The new operator<=> is mapped onto the existing functions
__libcpp_thread_id_equal and __libcpp_thread_id_less. Introducing a
new __libcpp_thread_id_compare_three_way might lead to more efficient
code. Given that we can still introduce __libcpp_thread_id_compare_three_way
later, for this commit I opted to not break ABI. If requested, I will
add __libcpp_thread_id_compare_three_way in a follow-up commit.
Implements part of P1614R2 "The Mothership has Landed"
Differential Revision: https://reviews.llvm.org/D131362
Since those features are general properties of the environment, it makes
sense to use them from libc++abi too, and so the name libcpp-has-no-xxx
doesn't make sense.
Differential Revision: https://reviews.llvm.org/D126482
All supported compilers have implemented this feature.
Therefore use the language version instead of the feature macro.
Reviewed By: #libc, philnik, ldionne, Quuxplusone
Differential Revision: https://reviews.llvm.org/D119865
I believe all four of these failures are directly due to the pattern where
allocations in the dylib are unobserved by the client program. If AIX32 and AIX64
don't support that, we should just disable the ASSERT_WITH_LIBRARY_INTERNAL_ALLOCATIONS
macro on AIX, and then we don't need to XFAIL these tests.
This also means I won't need to XFAIL a dozen other tests in D89057,
which rely heavily on ASSERT_WITH_LIBRARY_INTERNAL_ALLOCATIONS and
also currently fail on AIX.
See https://buildkite.com/llvm-project/libcxx-ci/builds/7669
Differential Revision: https://reviews.llvm.org/D116866
Casey Carter says, "We run std/thread/thread.mutex/thread.lock.algorithm/lock.pass.cpp
on every CI and it works fine with MSVC STL. I'm guessing this annotation predates
Billy's rewrite of std::lock in 2017-ish."
Differential Revision: https://reviews.llvm.org/D116712
Clang is gaining `auto(x)` support in D113393; sadly there
seems to be no feature-test macro for it. Zhihao is opening
a core issue for that macro.
Use `_LIBCPP_AUTO_CAST` where C++20 specifies we should use `auto(x)`;
stop using `__decay_copy(x)` in those places.
In fact, remove `__decay_copy` entirely. As of C++20, it's purely
a paper specification tool signifying "Return just `x`, but it was
perfect-forwarded, so we understand you're going to have to call
its move-constructor sometimes." I believe there's no reason we'd
ever need to do its operation explicitly in code.
This heisenbugs away a test failure on MinGW; see D112214.
Differential Revision: https://reviews.llvm.org/D115686
When P0883R2 was initially implemented in D103769 #pragma clang deprecated didn't exist yet.
We also forgot to cleanup usages in libc++ itself.
This takes care of both.
Differential Revision: https://reviews.llvm.org/D115995
This patch removes the ability to build the runtimes in the 32 bit
multilib configuration, i.e. using -m32. Instead of doing this, one
should cross-compile the runtimes for the appropriate target triple,
like we do for all other triples.
As it stands, -m32 has several issues, which all seem to be related to
the fact that it's not well supported by the operating systems that
libc++ support. The simplest path towards fixing this is to remove
support for the configuration, which is also the best course of action
if there is little interest for keeping that configuration. If there
is a desire to keep this configuration around, we'll need to do some
work to figure out the underlying issues and fix them.
Differential Revision: https://reviews.llvm.org/D114473
We never noticed it because our CI doesn't actually build against a C
library that doesn't have threading functionality, however building
against a truly thread-free platform surfaces these issues.
Differential Revision: https://reviews.llvm.org/D114242
