868 Commits

Author SHA1 Message Date
Stephan T. Lavavej
bf5cdd6358
[libc++][test] Fix issues found by MSVC's STL (#131787)
* libcxx/test/support/min_allocator.h
+ Fix `tiny_size_allocator::rebind` which mistakenly said `T` instead of
`U`.
*
libcxx/test/std/algorithms/alg.modifying.operations/alg.partitions/stable_partition.pass.cpp
  + `std::stable_partition` requires bidirectional iterators.
* libcxx/test/std/containers/sequences/vector.bool/max_size.pass.cpp
+ Fix allocator type given to `std::vector<bool>`. The element types are
required to match, [N5008](https://isocpp.org/files/papers/N5008.pdf)
\[container.alloc.reqmts\]/5: "*Mandates:* `allocator_type::value_type`
is the same as `X::value_type`."
* libcxx/test/std/time/time.clock/time.clock.utc/types.compile.pass.cpp
+ Mark `is_steady` as `[[maybe_unused]]`, as it appears within
`LIBCPP_STATIC_ASSERT` only.
*
libcxx/test/std/algorithms/alg.modifying.operations/alg.rotate/rotate.pass.cpp
*
libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/swap_ranges.pass.cpp
* libcxx/test/std/utilities/utility/utility.swap/swap_array.pass.cpp
+ Fix MSVC warning C4127 "conditional expression is constant".
`TEST_STD_AT_LEAST_23_OR_RUNTIME_EVALUATED` was introduced for this
purpose, so it should be used consistently.
* libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.pass.cpp
+ Fix `gcd()` precondition violation for `signed char`. This test case
was causing `-128` to be passed as a `signed char` to `gcd()`, which is
forbidden.
* libcxx/test/std/containers/sequences/array/assert.iterators.pass.cpp
*
libcxx/test/std/containers/sequences/vector/vector.modifiers/assert.push_back.invalidation.pass.cpp
*
libcxx/test/std/input.output/iostream.format/print.fun/no_file_description.pass.cpp
+ Split some REQUIRES and XFAIL lines. This is a "nice to have" for
MSVC's internal test harness, which is extremely simple and looks for
exact comment matches to skip tests. We can recognize the specific lines
"REQUIRES: has-unix-headers" and "XFAIL: msvc", but it's a headache to
maintain if they're chained with other conditions.
* libcxx/test/support/sized_allocator.h
+ Fix x86 truncation warnings. `std::allocator` takes `std::size_t`, so
we need to `static_cast`.
*
libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/offset_range.pass.cpp
+ Fix x86 truncation warning. `std::min()` is returning
`std::streamoff`, which was being unnecessarily narrowed to
`std::size_t`.
*
libcxx/test/std/algorithms/alg.sorting/alg.merge/inplace_merge_comp.pass.cpp
+ Fix MSVC warning C4127 "conditional expression is constant" for an
always-true branch. This was very recently introduced by #129008 making
`N` constexpr. As it's a local constant just nine lines above, we don't
need to test whether 100 is greater than 0.
2025-03-20 15:53:25 +08:00
A. Jiang
854a4f2bbb
[libc++] Implement part of P2562R1: constexpr std::inplace_merge (#129008)
Drive-by:
- Adds `constexpr_random.h` for pseudo-randomizing or shuffling in tests
for constant evaluation.
2025-03-19 07:42:23 +08:00
Mark de Wever
b271b44158
[libc++] Guard call_once against operator hijacking. (#128054) 2025-03-18 18:06:24 +01:00
A. Jiang
ba9aeedf8e
[libc++] Implement part of P2562R1: constexpr ranges::stable_sort (#128860)
Drive-by: Enables test coverage for `ranges::stable_sort` with proxy
iterators, and changes "constexpr in" to "constexpr since" in comments
in `<algorithm>`.
2025-03-07 01:27:48 +08:00
Martin Storsjö
f909b2229a
[libcxx] Provide locale conversions to tests through lit substitution (#105651)
There are 2 problems today that this PR resolves:

libcxx tests assume the thousands separator for fr_FR locale is x00A0 on
Windows. This currently fails when run on newer versions of Windows (it
seems to have been updated to the new correct value of 0x202F around
windows 11. The exact windows version where it changed doesn't seem to
be documented anywhere). Depending the OS version, you need different
values.

There are several ifdefs to determine the environment/platform-specific
locale conversion values and it leads to maintenance as things change
over time.

This PR includes the following changes:

- Provide the environment's locale conversion values through a
  substitution. The test can opt in by placing the substitution value in a
  define flag.
- Remove the platform ifdefs (the swapping of values between Windows,
  Linux, Apple, AIX).

This is accomplished through a lit feature action that fetches the
environment's locale conversions (lconv) for members like
'thousands_sep' that we need to provide. This should ensure that we
don't lose the effectiveness of the test itself.

In addition, as a result of the above, this PR:

- Fixes a handful of locale tests which unexpectedly fail on newer
  Windows versions.
- Resolves 3 XFAIL FIX-MEs.

Originally submitted in https://github.com/llvm/llvm-project/pull/86649.

Co-authored-by: Rodrigo Salazar <4rodrigosalazar@gmail.com>
2025-02-28 23:43:46 +02:00
Nikolas Klauser
15860446a8
[libc++] Fix basic_string not allowing max_size() elements to be stored (#125423)
Without this patch `basic_string` cannot be properly resized to be
`max_size()` elements in size, even if an allocation is successful.
`__grow_by` allocates one less element than required, resulting in an
out-of-bounds access. At the same time, `max_size()` has an off-by-one
error, since there has to be space to store the null terminator, which
is currently ignored.
2025-02-23 19:02:14 +01:00
Peng Liu
31824b2a11
[libc++] Fix shrink_to_fit to swap buffer only when capacity is strictly smaller (#127321)
The current implementation of the `shrink_to_fit()` function of
`basic_string` swaps to the newly allocated buffer when the new buffer
has the same capacity as the existing one. While this is not incorrect,
it is truly unnecessary to swap to an equally-sized buffer. With equal
capacity, we should keep using the existing buffer and simply deallocate
the new one, avoiding the extra work of copying elements.

The desired behavior was documented in the following comment within the
function:


61ad08792a/libcxx/include/string (L3560-L3566)

However, the existing implementation did not exactly conform to this
guideline, which is a QoI matter.

This PR modifies the `shrink_to_fit()` function to ensure that the
buffer is only swapped when the new allocation is strictly smaller than
the existing one. When the capacities are equal, the new buffer will be
discarded without copying the elements. This is achieved by including
the `==` check in the above conditional logic.
2025-02-22 14:50:48 +01:00
Mark de Wever
248716f814
[libc++] Fixes (|multi)_set spaceship operator. (#127326)
The operators did not have a _Compare template arguement. The fix
updates the generic container test to use allocators for all types used.
No other issues were found.

Fixes: #127095
2025-02-15 20:15:32 +01:00
A. Jiang
51ba9819b4
[libc++][test] Fix size_type issues with MinSequenceContainer and min_allocator (#126267)
`MinSequenceContainer::size` can be narrowing on 64-bit platforms, and
MSVC complains about such implicit conversion. This PR changes the
implicit conversion to explicit `static_cast`.

`min_allocator::allocate` and `min_allocator::deallocate` have
`ptrdiff_t` as the parameter type, which seems weird, because the
underlying `std::allocator`'s member functions take `size_t`. It seems
better to use `size_t` consistently.
2025-02-08 09:26:59 +08:00
Mark de Wever
aca829de13
[libc++][chrono] implements TAI clock. (#125550)
Implements parts of:
- P0355 Extending <chrono> to Calendars and Time Zones
- P1361 Integration of chrono with text formatting
- LWG3359 <chrono> leap second support should allow for negative leap
seconds
2025-02-06 17:55:02 +01:00
Peng Liu
cf9806eb4d
[libc++] Fix UB in bitwise logic of {std, ranges}::{fill, fill_n} algorithms (#122410)
This PR addresses an undefined behavior that arises when using the
`std::fill` and `std::fill_n` algorithms, as well as their ranges
counterparts `ranges::fill` and `ranges::fill_n`, with `vector<bool, Alloc>`
that utilizes a custom-sized allocator with small integral types.
2025-02-05 11:39:49 -05:00
Nikolas Klauser
24e70e3930
[libc++] Switch experimental library macros to 0/1 macros (#124030)
This is a continuation of what's been started in #89178.

As a drive-by, this also changes the PSTL macro to say `EXPERIMENTAL`
instead of `INCOMPLETE`.
2025-01-24 09:34:42 +01:00
James Y Knight
2b26ee6e79
[libcxx] Handle windows system error code mapping in std::error_code. (#93101)
The `std::error_code`/`std::error_category` functionality is designed to
support multiple error domains. On Unix, both system calls and libc
functions return the same error codes, and thus, libc++ today treats
`generic_category()` and `system_category()` as being equivalent.

However, on Windows, libc functions return `errno.h` error codes in the
`errno` global, but system calls return the very different `winerror.h`
error codes via `GetLastError()`.

As such, there is a need to map the winerror.h error codes into generic
errno codes. In libc++, however, the system_error facility does not
implement this mapping; instead the mapping is hidden inside libc++,
used directly by the std::filesystem implementation.

That has a few problems:

1. For std::filesystem APIs, the concrete windows error number is lost,
before users can see it. The intent of the distinction between
std::error_code and std::error_condition is that the error_code return
has the original (potentially more detailed) error code.

2. User-written code which calls Windows system APIs requires this same
mapping, so it also can also return error_code objects that other
(cross-platform) code can understand.

After this commit, an `error_code` with `generic_category()` is used to
report an error from `errno`, and, on Windows only, an `error_code` with
`system_category()` is used to report an error from `GetLastError()`. On
Unix, system_category remains identity-mapped to generic_category, but
is never used by libc++ itself.

The windows error code mapping is moved into system_error, so that
conversion of an `error_code` to `error_condition` correctly translates
the `system_category()` code into a `generic_category()` code, when
appropriate.

This allows code like:
`error_code(GetLastError(), system_category()) == errc::invalid_argument`
to work as expected -- as it does with MSVC STL.

(Continued from old phabricator review [D151493](https://reviews.llvm.org/D151493))
2025-01-08 17:34:48 -05:00
Nikolas Klauser
b9a2658a3e
[libc++][C++03] Use __cxx03/ headers in C++03 mode (#109002)
This patch implements the forwarding to frozen C++03 headers as
discussed in
https://discourse.llvm.org/t/rfc-freezing-c-03-headers-in-libc. In the
RFC, we initially proposed selecting the right headers from the Clang
driver, however consensus seemed to steer towards handling this in the
library itself. This patch implements that direction.

At a high level, the changes basically amount to making each public
header look like this:

```
// inside <vector>
#ifdef _LIBCPP_CXX03_LANG
#  include <__cxx03/vector>
#else
  // normal <vector> content
#endif
```

In most cases, public headers are simple umbrella headers so there isn't
much code in the #else branch. In other cases, the #else branch contains
the actual implementation of the header.
2024-12-21 13:01:48 +01:00
Peng Liu
eacdbc269e
[libc++][test] Fix invalid const conversion in limited_allocator (#118189)
This patch fixes a const-qualification on the return type of a method
of `limited_allocator`, which is widely used for testing allocator-aware
containers.
2024-12-10 10:24:40 -05:00
Louis Dionne
10ef00faf1 [libc++][NFC] Run clang-format on test_allocator.h 2024-12-09 11:47:14 -05:00
Peng Liu
a821937b6d
[libc++][test] Refactor increasing_allocator (#115671)
The increasing_allocator<T> class, originally introduced to test shrink_to_fit()
for std::vector, std::vector<bool>, and std::basic_string, has duplicated
definitions across several test files. Given the potential utility of this
class for capacity-related tests in various sequence containers, this patch
refactors the definition of increasing_allocator<T> into a single, reusable
location.
2024-12-05 15:44:05 -05:00
Nikolas Klauser
c6f3b7bcd0
[libc++] Refactor the configuration macros to being always defined (#112094)
This is a follow-up to #89178. This updates the `<__config_site>`
macros.
2024-11-06 10:39:19 +01:00
Louis Dionne
76f993b6f6 [libc++][NFC] Remove unused header in test/support 2024-11-05 13:18:36 -05:00
serge-sans-paille
71315698c9
[clang] Warn about memset/memcpy to NonTriviallyCopyable types (#111434)
This implements a warning that's similar to what GCC does in that
context: both memcpy and memset require their first and second operand
to be trivially copyable, let's warn if that's not the case.
2024-10-28 20:40:52 +00:00
Hui
0be1883c36
[libc++] Implement P0429R9 std::flat_map (#98643)
Around half of the tests are based on the tests Arthur O'Dwyer's
original implementation of std::flat_map, with modifications and
removals.

partially implement #105190
2024-10-26 18:58:53 +01:00
A. Jiang
3fc0d94ce5
[libc++][test] Make macro detection more friendly to MSVC (#113633)
MSVC STL's test suite is a bit nervous about replacing non-macro-defined
identifiers with `0` (see also
https://learn.microsoft.com/en-us/cpp/error-messages/compiler-warnings/compiler-warning-level-4-c4668?view=msvc-170).

On MSVC (and MS-compatible mode of other compilers), `long double` has
the same format (IEEE-754 binary64) as `double`, so it should be OK to
define `TEST_LONG_DOUBLE_IS_DOUBLE` when `_MSC_VER` is defined. Such
detection should be performed first.
2024-10-26 13:46:59 +08:00
Michael Jones
6c4267fb17
[libcxx][libc] Hand in Hand PoC with from_chars (#91651)
Implements std::from_chars for float and double.

The implementation uses LLVM-libc to do the real parsing. Since this is
the first time libc++
uses LLVM-libc there is a bit of additional infrastructure code. The
patch is based on the
[RFC] Project Hand In Hand (LLVM-libc/libc++ code sharing)

https://discourse.llvm.org/t/rfc-project-hand-in-hand-llvm-libc-libc-code-sharing/77701
2024-10-21 15:04:06 -07:00
Doug Wyatt
954836634a
[libc++] Make __libcpp_verbose_abort() noexcept like std::terminate() (#109151)
Make __libcpp_verbose_abort() noexcept (it is already noreturn), to
match std::terminate(). Clang's function effect analysis can use this to
ignore such functions as being beyond its scope. (See
https://github.com/llvm/llvm-project/pull/99656).
2024-10-17 10:38:29 -04:00
Nikolas Klauser
ba87515fea
[libc++][RFC] Always define internal feature test macros (#89178)
Currently, the library-internal feature test macros are only defined if
the feature is not available, and always have the prefix
`_LIBCPP_HAS_NO_`. This patch changes that, so that they are always
defined and have the prefix `_LIBCPP_HAS_` instead. This changes the
canonical use of these macros to `#if _LIBCPP_HAS_FEATURE`, which means
that using an undefined macro (e.g. due to a missing include) is
diagnosed now. While this is rather unlikely currently, a similar change
in `<__configuration/availability.h>` caught a few bugs. This also
improves readability, since it removes the double-negation of `#ifndef
_LIBCPP_HAS_NO_FEATURE`.

The current patch only touches the macros defined in `<__config>`. If
people are happy with this approach, I'll make a follow-up PR to also
change the macros defined in `<__config_site>`.
2024-10-12 09:49:52 +02:00
Nikolas Klauser
d278fa5e1a
[libc++] Fix constant initialization of unique_ptr in C++17 and prior (#108956)
This is already tested in
`std/utilities/smartptr/unique.ptr/unique.ptr.class/unique.ptr.ctor/default.pass.cpp`
except that `TEST_CONSTINIT` doesn't do anything before C++20 without
this patch.
2024-10-02 17:09:06 +02:00
Louis Dionne
09e3a36058
[libc++][modules] Fix missing and incorrect includes (#108850)
This patch adds a large number of missing includes in the libc++ headers
and the test suite. Those were found as part of the effort to move
towards a mostly monolithic top-level std module.
2024-09-16 15:06:20 -04:00
Louis Dionne
33325524f5
[libc++][modules] Refactor poisoned_hash_helper (#108296)
The poisoned_hash_helper header was relying on an implicit forward
declaration of std::hash located in <type_traits>. When we improve the
modularization of the library, that causes issues, in addition to being
a fundamentally non-portable assumption in the test suite.

It turns out that the reason for relying on a forward declaration is to
be able to test that std::hash is *not* provided if we don't include any
header that provides it. But testing that is actually both non-portable
and not really useful.

Indeed, what harm does it make if additional headers provide std::hash
specializations? That would certainly be conforming -- the Standard
never requires an implementation to avoid providing a declaration when a
given header is included, instead it mandates what *must* be provided
for sure. In that spirit, it would be conforming for e.g. `<cstddef>` to
define the hash specializations if that was our desire. I also don't
read https://wg21.link/P0513R0 as going against that statement. Hence,
this patch just removes that test which doesn't carry its weight.

Fixes #56938
2024-09-12 15:07:49 -04:00
Louis Dionne
99174842ae
[libc++] Make std::jthread supported in non-experimental mode (#107900)
We waited before supporting std::jthread fully because we wanted to
investigate other implementation strategies (in particular one involving
std::mutex). Since then, we did some benchmarking and decided that we
wouldn't be moving forward with std::mutex. Hence, there is no real
reason to punt on making std::jthread & friends non-experimental.
2024-09-12 09:48:59 -04:00
Nikolas Klauser
748023dc32
[libc++][NFC] Replace _LIBCPP_NORETURN and TEST_NORETURN with [[noreturn]] (#80455)
`[[__noreturn__]]` is now always available, so we can simply use the
attribute directly instead of through a macro.
2024-09-11 08:59:46 +02:00
A. Jiang
46a76c3334
[libc++][test] LWG2593: Moved-from state of Allocators (#107344)
The resolution of LWG2593 didn't require the standard library
implementation to change. It merely strengthened requirements on
user-defined allocator types and allowed the implementation to make
stronger assumptions. The status is tentatively set to Nothing To Do.

However, `test_allocator` in libc++'s test suit needs to be fixed to
conform to the strengthened requirements.

Closes #100220.
2024-09-10 09:53:23 -04:00
Louis Dionne
953af0e7f1 [libc++][NFC] Increase consistency for namespace closing comments 2024-09-05 12:41:20 -04:00
David Spickett
c792de28df
[libcxx][test] Add macro for when long double is just double (#106708)
This removes the need for the long list of platforms in
strong_order_long_double_verify.
2024-08-30 15:05:29 +01:00
A. Jiang
7808541fde
[libc++] P2747R2: constexpr placement new (library part) (#105768)
This patch implements https://wg21.link/P2747R2.

The library changes affect direct `operator new` and `operator new[]`
calls even when the core language changes are absent.

The changes are not available for MS ABI because the `operator new` and
`operator new[]` are from VCRuntime's `<vcruntime_new.h>`. A feature
request was submitted for that [1].

As a drive-by change, the patch reformatted the whole `new.pass.cpp` and
`new_array.pass.cpp` tests.

Closes #105427

[1]: https://developercommunity.visualstudio.com/t/constexpr-for-placement-operator-newope/10730304.
2024-08-28 09:35:57 -04:00
Louis Dionne
06edc1c07b
[libc++] Avoid including <__config> directly in the test suite (#106080)
Fixes #105878
2024-08-26 17:52:33 -04:00
Stephan T. Lavavej
886b76128f
[libc++][test] Fix msvc_is_lock_free_macro_value() (#105876)
Followup to #99570.

* `TEST_COMPILER_MSVC` must be tested for `defined`ness, as it is
everywhere else.
+ Definition:
52a7116f5c/libcxx/test/support/test_macros.h (L71-L72)
+ Example usage:
52a7116f5c/libcxx/test/std/utilities/function.objects/func.not_fn/not_fn.pass.cpp (L248)
+ Fixes: `llvm-project\libcxx\test\support\atomic_helpers.h(33): fatal
error C1017: invalid integer constant expression`
* Fix bogus return type: `msvc_is_lock_free_macro_value()` returns `2`
or `0`, so it needs to return `int`.
+ Fixes: `llvm-project\libcxx\test\support\atomic_helpers.h(41): warning
C4305: 'return': truncation from 'int' to 'bool'`
* Clarity improvement: also add parens when mixing bitwise with
arithmetic operators.
2024-08-24 09:55:17 -07:00
Nikolas Klauser
9ff0468436
[libc++] Refactor the std::unique_lock tests (#102151)
This makes some of the tests not flaky anymore, updates some tests to
also work in C++03 and modernizes them in general.
2024-08-22 11:47:56 +02:00
Louis Dionne
f73050e722
[libc++] Fix several double-moves in the code base (#104616)
This patch hardens the "test iterators" we use to test algorithms by
ensuring that they don't get double-moved. As a result of this
hardening, the tests started reporting multiple failures where we would
double-move iterators, which are being fixed in this patch.

In particular:
- Fixed a double-move in pstl.partition
- Add coverage for begin()/end() in subrange tests
- Fix tests for ranges::ends_with and ranges::contains, which were
  incorrectly calling begin() twice on the same subrange containing
  non-copyable input iterators.

Fixes #100709
2024-08-20 14:36:11 -04:00
Joseph Huber
3c603f857c [libcxx][fix] Rename incorrect filename variable
Summary:
This used an old name I forgot to fix, linter didn't catch it because it
was behind `ifdef` and the branch which I tested it on I forgot to
update the one I landed.
2024-08-16 13:50:05 -05:00
Joseph Huber
f71b638651
[libcxx] Use aligned_alloc for testing instead of posix_memalign (#101748)
Summary:
The `aligned_alloc` function is the C11 replacement for
`posix_memalign`. We should favor the C standard over the POSIX standard
so more C library implementations can run the tests.
2024-08-15 07:11:31 -05:00
Joseph Huber
9e87061404
[libcxx] Adjust inline assembly constraints for the AMDGPU target (#101747)
Summary:
These assembly constraints are illegal / invalid on the AMDGPU target.
The `r` constraint is only valid on inputs and the `m` constraint isn't
accepted at all. The NVPTX target can handle them because it uses a more
permissive virtual machine (PTX is an IR). Simply add exceptions on the
target to make these work.
2024-08-14 13:42:46 -05:00
Joseph Huber
3b7b2f2efc
[libcxx] Add fallback to standard C when unistd is unavailable (#102005)
Summary:
This utility function gets a temp file to use for tests. It either uses
WIN32 or POSIX to create it. Some targets only follow the C standard,
and this test case will fail. This patch simply adds a fallback that
uses the `tmpnam` function from standard C. This function isn't ideal,
but it is good enough for our use-case.

---------

Co-authored-by: Mark de Wever <zar-rpg@xs4all.nl>
2024-08-14 13:40:17 -05:00
Louis Dionne
b368404dee
[libc++][NFC] Fix typo in count_new.h (#102049)
A function was named alocate_aligned_impl, when it should have been
named allocate_aligned_impl.
2024-08-12 17:04:59 -04:00
Mark de Wever
4dee6411e0
[libc++] Implements LWG3130. (#101889)
This adds addressof at the required places in [input.output]. Some of
the new tests failed since string used operator& internally. These have
been fixed too.

Note the new fstream tests perform output to a basic_string instead of a
double. Using a double requires num_get specialization

num_get<CharT, istreambuf_iterator<CharT,
char_traits_operator_hijacker<CharT>>

This facet is not present in the locale database so the conversion would
fail due to a missing locale facet. Using basic_string avoids using the
locale.

As a drive-by fixes several bugs in the ofstream.cons tests. These
tested ifstream instead of ofstream with an open mode.

Implements:
- LWG3130 [input.output] needs many addressof

Closes #100246.
2024-08-06 19:47:56 +02:00
PaulXiCao
72825fde03
[libc++][math] Fix undue overflowing of std::hypot(x,y,z) (#100820)
This is in relation to mr #93350. It was merged to main, but reverted
because of failing sanitizer builds on PowerPC.

The fix includes replacing the hard-coded threshold constants (e.g.
`__overflow_threshold`) for different floating-point sizes by a general
computation using `std::ldexp`. Thus, it should now work for all architectures.
This has the drawback of not being `constexpr` anymore as `std::ldexp`
is not implemented as `constexpr` (even though the standard mandates it
for C++23).

Closes #92782
2024-08-05 16:08:47 -04:00
Nikolas Klauser
5dfdac74ca
[libc++][NFC] Avoid opening namespace std in the tests (#94160)
This also adds a few FIXMEs where we use UB in the tests.
2024-08-01 10:57:21 +02:00
Louis Dionne
6a54dfbfe5 [libc++][NFC] Add missing license headers
Also standardize the license comment in several files where it was
different from what we normally do.
2024-07-31 12:58:09 -04:00
nicole mazzuca
c6b192ac2e
[libc++][test] Do not assume array::iterator is a pointer (#100603)
In the tests I added for `ranges::find_last{_if{_not}}`, I accidentally
introduced an assumption that `same_as<array<T, 0>::iterator, T*>`; this
is a faulty assumption on MSVC-STL.

Fixes #100498.
2024-07-30 02:28:56 -07:00
Louis Dionne
cc1dfb37aa
[libc++] Fix bug in atomic_ref's calculation of lock_free-ness (#99570)
The builtin __atomic_always_lock_free takes into account the type of the
pointer provided as the second argument. Because we were passing void*,
rather than T*, the calculation failed. This meant that
atomic_ref<T>::is_always_lock_free was only true for char & bool.

This bug exists elsewhere in the atomic library (when using GCC, we fail
to pass a pointer at all, and we fail to correctly align the atomic like
_Atomic would).

This change also attempts to start sorting out testing difficulties with
this function that caused the bug to exist by using the 
__GCC_ATOMIC_(CHAR|SHORT|INT|LONG|LLONG|POINTER)_IS_LOCK_FREE predefined
macros to establish an expected value for `is_always_lock_free` and 
`is_lock_free` for the respective types, as well as types with matching 
sizes and compatible alignment values.

Using these compiler pre-defines we can actually validate that certain
types, like char and int, are actually always lock free like they are on
every platform in the wild.

Note that this patch was actually authored by Eric Fiselier but I picked 
up the patch and GitHub won't let me set Eric as the primary author.

Co-authored-by: Eric Fiselier <eric@efcs.ca>
2024-07-26 14:10:06 -04:00
Mark de Wever
8d3252a898
[libc++][spaceship] Implements X::iterator container requirements. (#99343)
This implements the requirements for the container iterator requirements
for array, deque, vector, and `vector<bool>`.

Implements:
- LWG3352 strong_equality isn't a thing

Implements parts of:
- P1614R2 The Mothership has Landed

Fixes: https://github.com/llvm/llvm-project/issues/62486
2024-07-24 19:42:48 +02:00