This effort has quite a history:
- This was first attempted in 2022 via bed3240bf7d1, which broke
std::shared_ptr<T const> and caused the change to be reverted in
9138666f5464.
- We then re-attempted landing the change in 276ca87382b8 after fixing
std::shared_ptr, but reports were made that this broke code en masse
within Google. This led to the patch being reverted again in
a54d028895c9 with the goal to land this again with a migration path for
vendors.
This patch re-lands the removal while providing a migration path for
vendors by providing the `_LIBCPP_ENABLE_REMOVED_ALLOCATOR_CONST` macro.
This macro will be honored for the LLVM 19 release and will be removed
after that, at which point allocator<const T> will be removed
unconditionally.
Fixes#73665
We were not making any distinction between e.g. the "Apple-flavored"
libc++ built from trunk and the system-provided standard library on
Apple platforms. For example, any test that would be XFAILed on a
back-deployment target would unexpectedly pass when run on that
deployment target against the tip of trunk Apple-flavored libc++. In
reality, that test would be expected to pass because we're running
against the latest libc++, even if it is Apple-flavored.
To solve this issue, we introduce a new feature that describes whether
the Standard Library in use is the one provided by the system by
default, and that notion is different from the underlying standard
library flavor. We also refactor the existing Lit features to make a
distinction between availability markup and the library we're running
against at runtime, which otherwise limit the flexibility of what we can
express in the test suite. Finally, we refactor some of the
back-deployment versions that were incorrect (such as thinking that LLVM
10 was introduced in macOS 11, when in reality macOS 11 was synced with
LLVM 11).
Fixes#82107
Clang currently has a bug in the __has_unique_object_representations
builtin where it doesn't provide consistent answers based on the order
of instantiation of templates. This was reported as #95311.
This patch adds a workaround in libc++ to avoid breaking users until
Clang has been fixed. It also revamps the tests a bit.
This changes the `is_swappable` implementation to use variable templates
first and basing the class templates on that. This avoids instantiating
them when the `_v` versions are used, which are generally less resource
intensive.
This reverts commit d868f0970, which was shown to break some code and we
don't know yet whether the code should be valid or not. Reverting until
we've had time to figure it out next week.
When I filed LWG4110 after the discussion in #93071, I thought it was
going to be a straightforward fix. It turns out that it isn't, so we
should stay in the state where libc++ is Standards conforming even if
that state leads to some reasonable code being rejected by the library.
Once WG21 figures out what to do with this issue and votes on it, we'll
implement it through our normal means.
This reverts f638f7b6a7c2 and 16f2aa1a2ddf.
This PR carves out small portion of the test in subject to avoid the
following failure when unicode is not available.
```
# | Assertion failure: result == expected .../formatter.char.funsigned-char.pass.cpp 56
# |
# | Format string ?}
# | Expected output '\x{80}'
# | Actual output '�'
```
This was traced down to different definition of
`__code_point_view::__consume()` under macro_LIBCXX_HAS_NO_UNICODE which
is called inside `__formatter::__escape()`. The `__consume()` returns
`__ok` and code assumes that escaped sequence was already written but it
is not., thus the failure. Here is the snippen code we fall into:
```
typename __unicode::__consume_result __result = __view.__consume();
if (__result.__status == __unicode::__consume_result::__ok) {
__escape = __formatter::__is_escaped_sequence_written(__str, __result.__code_point, __escape, __mark);
```
This avoids breaking code that should arguably be valid but technically
isn't after enforcing the constraints on shared_ptr's constructors. A
new LWG issue was filed to fix this in the Standard.
This patch applies the expected resolution of this issue to avoid
flip-flopping users whose code should always be considered valid.
See #93071 for more context.
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
This patch improves the preservation of qualifiers and loss of type
sugar in TemplateNames.
This problem is analogous to https://reviews.llvm.org/D112374 and this
patch takes a very similar approach to that patch, except the impact
here is much lesser.
When a TemplateName was written bare, without qualifications, we
wouldn't produce a QualifiedTemplate which could be used to disambiguate
it from a Canonical TemplateName. This had effects in the TemplateName
printer, which had workarounds to deal with this, and wouldn't print the
TemplateName as-written in most situations.
There are also some related fixes to help preserve this type sugar along
the way into diagnostics, so that this patch can be properly tested.
- Fix dropping the template keyword.
- Fix type deduction to preserve sugar in TST TemplateNames.
* Guard `std::__make_from_tuple_impl` tests with `#ifdef _LIBCPP_VERSION` and `LIBCPP_STATIC_ASSERT`.
* Change `_LIBCPP_CONSTEXPR_SINCE_CXX20` to `TEST_CONSTEXPR_CXX20`.
+ Other functions in `variant.swap/swap.pass.cpp` were already using the proper test macro.
* Mark `what` as `[[maybe_unused]]` when used by `TEST_LIBCPP_REQUIRE`.
+ This updates one occurrence in `libcxx/test/libcxx` for consistency.
* Windows `_putenv_s()` takes 2 arguments, not 3.
+ See MSVC documentation: https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/putenv-s-wputenv-s?view=msvc-170
+ POSIX `setenv()` takes `int overwrite`, but Windows `_putenv_s()` always overwrites.
* Avoid non-Standard zero-length arrays.
+ Followup to #74183 and #79792.
* Add `operator++()` to `unsized_it`.
+ The Standard requires this due to [N4981][] [move.iter.requirements]/1 "The template parameter `Iterator` shall
either meet the *Cpp17InputIterator* requirements ([input.iterators])
or model `input_iterator` ([iterator.concept.input])."
+ MSVC's STL requires this because it has a strengthened exception
specification in `move_iterator` that inspects the underlying iterator's
increment operator.
* `uniform_int_distribution` forbids `int8_t`/`uint8_t`.
+ See [N4981][] [rand.req.genl]/1.5. MSVC's STL enforces this.
+ Note that when changing the distribution's `IntType`, we need to be
careful to preserve the original value range of `[0, max_input]`.
* fstreams are constructible from `const fs::path::value_type*` on wide systems.
+ See [ifstream.cons], [ofstream.cons], [fstream.cons].
* In `msvc_stdlib_force_include.h`, map `_HAS_CXX23` to `TEST_STD_VER` 23 instead of 99.
+ On 2023-05-23, 71400505ca
started recognizing 23 as a distinct value.
* Fix test name typo: `destory_elements.pass.cpp` => `destroy_elements.pass.cpp`
[N4981]: https://wg21.link/N4981
Libc++ has no separate C++98 support, it uses C++03 instead. This
removes some obsolete c++98 markers in the test.
Thanks to @StephanTLavavej for spotting this.
`remove_cv_t` and `remove_all_extents_t` are taken care of by the
built-in trait, so we don't need to use them directly.
---------
Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
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 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
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.
This moves the definition of a `pair` constructor for `<tuple>` to
`<__utility/pair.h>` and uses the forward declaration of `pair` in
`<tuple>` instead of including the definition.
Implement [LWG3528](https://wg21.link/LWG3528).
Based on LWG3528(https://wg21.link/LWG3528) and
http://eel.is/c++draft/description#structure.requirements-9, the
standard allows to impose requirements, we constraint
`std::make_from_tuple` to make `std::make_from_tuple` SFINAE friendly
and also avoid worse diagnostic messages. We still keep the constraints
of `std::__make_from_tuple_impl` so that `std::__make_from_tuple_impl`
will have the same advantages when used alone.
---------
Signed-off-by: yronglin <yronglin777@gmail.com>
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).
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"});
```
