This patch reverts 9b832b72 (#87111):
- [libc++] Deprecated `shared_ptr` Atomic Access APIs as per P0718R2
- [libc++] Implemented P2869R3: Remove Deprecated `shared_ptr` Atomic Access APIs from C++26
As explained in [1], the suggested replacement in P2869R3 is `__cpp_lib_atomic_shared_ptr`,
which libc++ does not yet implement. Let's not deprecate the old way of doing things before
the new way of doing things exists.
[1]: https://github.com/llvm/llvm-project/pull/87111#issuecomment-2112740039
Since we have already addressed the LWG issue, this PR marks LWG3951 as
implemented.
Signed-off-by: yronglin <yronglin777@gmail.com>
Co-authored-by: A. Jiang <de34@live.cn>
[P2845R8](https://wg21.link/P2845R8) "Formatting of
`std::filesystem::path`" and [P2587R3](https://wg21.link/P2587R3)
"`to_string` or not `to_string`" are C++26 features, so they should be
marked accordingly in `generate_feature_test_macro_components.py`.
I verified that without my changes, running the script produced no
edits. Then with my changes, I ran the script to regenerate all files,
with no other manual edits.
Found while running libc++'s tests with MSVC's STL, which noticed this
because it's currently a C++23-only implementation.
Note that @H-G-Hristov has a draft implementation of P2587R3: #78100
This PR implements [LWG2381](https://cplusplus.github.io/LWG/issue2381)
by rejecting `'i'`, `'I'`, `'n'`, `'N'` in FP parsing, as inf and NaN
are intendedly rejected by that LWG issue.
The source character array used for parsing is
`"0123456789abcdefABCDEFxX+-pPiInN"`, whose first 26 or 28 characters
are used for parsing integers or floating-point values respectively.
Previously, libc++ used 32 characters, including `'i'`, `'I'`, `'n'`,
`'N'`, for FP parsing, which was inconsistent with LWG2381. This PR also
replaces magic numbers 26 and 28 (formerly 32) with named constants.
Drive-by change: when the first character (possibly after the leading
`'+'` or `'-'`) is not a decimal digit but an acceptable character
(e.g., `'p'` or `'e'`), the character is not accumulated now (per Stage
2 in [facet.num.get.virtuals]/3).
#65168 may be rendered invalid, see
https://github.com/llvm/llvm-project/pull/65168#issuecomment-1868533342.
Apple back-deployment targets remain broken, likely due to dylib. XFAIL
is marked in related tests.
---------
Co-authored-by: Mark de Wever <koraq@xs4all.nl>
## Abstract
This pull request implements LWG3672: `common_iterator::operator->()`
should return by value. The current implementation specifies that this
function should return the underlying pointer by reference (`T*
const&`), but it would be more intuitive to return it by value (`T*`).
## Reference
- [Draft C++ Standard:
[common.iter.access]](https://eel.is/c++draft/common.iter.access)
- [LWG3672](https://cplusplus.github.io/LWG/issue3672)
I strongly suspect nobody ever used that macro since it wasn't very well
known. Furthermore, it only affects a handful of diagnostics and I think
it makes sense to either provide them unconditionally, or to not
provided them at all.
Implement
- LWG4053 Unary call to `std::views::repeat` does not decay the argument
- LWG4054 Repeating a `repeat_view` should repeat the view
Signed-off-by: yronglin <yronglin777@gmail.com>
This pull request implements LWG3984: ranges::to's recursion branch
may be ill-formed.
In the current implementation, ranges::to's recursion branch pipes the
range into a `views::transform(/* lambda */)`, which is a __range_adaptor_closure
object. In libc++, the pipe operator of __range_adaptor_closure requires a
viewable_range, so the following code won't compile, as the type of lvalue
`r` doesn't model viewable_range:
#include <ranges>
#include <vector>
#include <list>
int main() {
std::vector<std::vector<int>> v;
auto r = std::views::all(std::move(v));
auto l = std::ranges::to<std::list<std::list<int>>>(r);
}
Co-authored-by: A. Jiang <de34@live.cn>
The change increments the size of the lookup table considerably. The
table has an "upper boundary" check. The removal of the code units with
the property Grapheme_Extend=Yes removes the range E0100..E01EF. This
breaks the trailing large continuous section in two parts. This will be
improved in a followup patch.
Implements:
- P2713R1 Escaping improvements in std::format
- LWG3965 Incorrect example in [format.string.escaped] p3 for formatting
of combining characters
```
---------------------------------------------------------
Benchmark Before After
---------------------------------------------------------
BM_ascii_escaped<char> 95696 ns 110704 ns
BM_unicode_escaped<char> 89311 ns 101371 ns
BM_cyrillic_escaped<char> 58633 ns 63329 ns
BM_japanese_escaped<char> 44500 ns 41223 ns
BM_emoji_escaped<char> 99156 ns 111022 ns
BM_ascii_escaped<wchar_t> 92245 ns 112441 ns
BM_unicode_escaped<wchar_t> 80970 ns 102776 ns
BM_cyrillic_escaped<wchar_t> 51253 ns 58977 ns
BM_japanese_escaped<wchar_t> 37252 ns 36885 ns
BM_emoji_escaped<wchar_t> 96226 ns 115885 ns
```
This patch implements LWG4023 by adding explicit assertions for the
added preconditions and also fixes a few tests that were violating these
preconditions.
CMake has landed experimental support for using the Standard modules.
This will be part of the CMake 3.30 release. This updates the build
instructions to use modules with CMake.
The changes have been tested locally.
---------
Co-authored-by: Will Hawkins <whh8b@obs.cr>
This patch finalizes the std::ranges::range_adaptor_closure
class template from https://wg21.link/P2387R3.
// [range.adaptor.object], range adaptor objects
template<class D>
requires is_class_v<D> && same_as<D, remove_cv_t<D>>
class range_adaptor_closure { };
The current implementation of __range_adaptor_closure was introduced
in ee44dd8062a26541808fc0d3fd5c6703e19f6016 and has served as the
foundation for the range adaptors in libc++ for a while. This patch
keeps its implementation, with the exception of the following changes:
- __range_adaptor_closure now includes the missing constraints
`is_class_v<D> && same_as<D, remove_cv_t<D>>` to restrict the
type of class that can inherit from it. (https://eel.is/c++draft/ranges.syn)
- The operator| of __range_adaptor_closure no longer requires its
first argument to model viewable_range. (https://eel.is/c++draft/range.adaptor.object#1)
- The _RangeAdaptorClosure concept is refined to exclude cases where
T models range or where T has base classes of type range_adaptor_closure<U>
for another type U. (https://eel.is/c++draft/range.adaptor.object#2)
This adds the local_info type and its formatting options.
The usage of the local_info object will be done in separate patches.
Implements parts of:
- P0355 Extending to Calendars and Time Zones
- P1361 Integration of chrono with text formatting
When we initially implemented the C++20 synchronization library, we
reluctantly accepted for the implementation to be backported to C++03
upon request from the person who provided the patch. This was when we
were only starting to have experience with the issues this can create,
so we flinched. Nowadays, we have a much stricter stance about not
backporting features to previous standards.
We have recently started fixing several bugs (and near bugs) in our
implementation of the synchronization library. A recurring theme during
these reviews has been how difficult to understand the current code is,
and upon inspection it becomes clear that being able to use a few recent
C++ features (in particular lambdas) would help a great deal. The code
would still be pretty intricate, but it would be a lot easier to reason
about the flow of callbacks through things like
__thread_poll_with_backoff.
As a result, this patch deprecates support for the synchronization
library before C++20. In the next release, we can remove that support
entirely.
## Abstract
This pull request implements [P3029R1](https://wg21.link/P3029R1). The
paper discusses the current behavior of `mdspan`'s most common
pointer-indices CTAD, where the `Extents` template parameter is deduced
as `dextents` (dynamic extents), even when passing compile-time constant
values. The author believes this behavior is suboptimal, as it doesn't
take advantage of the compile-time information. The proposed change
suggests deducing static extents if `integral_constant`-like constants
are passed, resulting in more intuitive syntax and less error-prone
code.
## Reference
- [P3029R1](https://wg21.link/P3029R1)
- [Draft C++ Standard: [span.syn]](https://eel.is/c++draft/span.syn)
- [Draft C++ Standard: [mdspan.syn]](https://eel.is/c++draft/mdspan.syn)
This pull request implements LWG3643: Missing constexpr in
std::counted_iterator. Specifically, one overload of
std::counted_operator::operator++ was not marked as constexpr,
despite being eligible for it after the introduction of try-block
support in constexpr functions in C++20.
Adds the sys_info class and time_zone::get_info(). The code still has a
few quirks and has not been optimized for performance yet.
The returned sys_info is compared against the output of the zdump tool
in the test giving confidence the implementation is correct.
Implements parts of:
- P0355 Extending <chrono> to Calendars and Time Zones
Implements:
- LWGXXXX The sys_info range should be affected by save
This was actually already implemented in the initial version of
std::expected, but this patch adds test coverage and makes it more
explicit that we intend to make these functions noexcept.
