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.
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
Currently, libc++'s `bitset`, `forward_list`, and `list` have
non-conforming member typedef name `base`. The typedef is private, but
can cause ambiguity in name lookup.
Some other classes in libc++ that are either implementation details or
not precisely specified by the standard also have member typdef `base`.
I think this can still be conforming.
Follows up #80706 and #111127.
`overload_compare_iterator` only supports operations required for
forward iterators. On the other hand, it is used for output iterators of
uninitialized memory algorithms, which requires it to be forward
iterator.
As a result, `overload_compare_iterator<I>::iterator_category` should
always be `std::forward_iterator_tag` if we don't extend its ability.
The correct `iterator_category` can prevent standard library
implementations like MSVC STL attempting random access operations on
`overload_compare_iterator`.
Fixes#74756.
Previously, SFINAE constraints and exception specification propagation
were missing in the return type of libc++'s `std::mem_fn`. The
requirements on expression-equivalence (or even plain "equivalent" in
pre-C++20 specification) in [func.memfn] are actually requiring them.
This PR adds the missed stuffs. Fixes#86043.
Drive-by changes:
- removing no longer used `__invoke_return`,
- updating synopsis comments in several files, and
- merging several test files for `mem_fn` into one.
[template.bitset.general] indicates that `bitset` shouldn't have member
typedef-names `iterator` and `const_iterator`. Currently libc++'s
typedef-names are causing ambiguity in name lookup, which isn't
conforming.
As these iterator types are themselves useful, I think we should just
use __uglified member typedef-names for them.
Fixes#111125
It turns out that we can never do bounds-checking for unique_ptrs with
custom deleters, except when converting from a unique_ptr with a default
deleter to one with a custom deleter.
If we had an API like `std::make_unique` that allowed passing a custom
deleter, we could at least get bounds checking when the unique_ptr is
created through those APIs, but for now that is not possible.
Fixes#110683
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.
Instead of changing the cast sequence to implicit conversion in
_`voidify`_, I think it is better to totally remove `__voidify` and use
`static_cast` to `void*`, which has equivalent effects.
Test coverage for const iterators are removed.
Now most affected algorithms are underconstrained, for which I submitted
[LWG3888](https://cplusplus.github.io/LWG/issue3888). I'm not sure
whether we should speculatively implement it at this moment, and thus
haven't added any `*.verify.cpp`.
In some control block types and `optional`, the stored objects are
changed to have cv-unqualified type.
Fixes#105119.
This allows catching OOB accesses inside `unique_ptr<T[]>` when the size
of the allocation is known. The size of the allocation can be known when
the unique_ptr has been created with make_unique & friends or when the
type necessitates an array cookie before the allocation.
This is a re-aplpication of 45a09d181 which had been reverted in
f11abac6 due to unrelated CI failures.
This reverts 3 commits:
45a09d181124bc3244d4bc6bd3bc1e
The GitHub pre-merge CI has been broken since this PR went in. This
change reverts it to see if I can get the pre-merge CI working again.
This allows catching OOB accesses inside `unique_ptr<T[]>` when the size
of the allocation is known. The size of the allocation can be known when
the unique_ptr has been created with make_unique & friends or when the
type necessitates an array cookie before the allocation.
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.
Works towards P0619R4 / #99985.
The use of `std::get_temporary_buffer` and `std::return_temporary_buffer`
are replaced with `unique_ptr`-based RAII buffer holder.
Escape hatches:
- `_LIBCPP_ENABLE_CXX20_REMOVED_TEMPORARY_BUFFER` restores
`std::get_temporary_buffer` and `std::return_temporary_buffer`.
Drive-by changes:
- In `<syncstream>`, states that `get_temporary_buffer` is now removed,
because `<syncstream>` is added in C++20.
This significantly simplifies the code, improves compile times and
improves the object layout of types using `__compressed_pair` in the
unstable ABI. The only downside is that this is extremely ABI sensitive
and pedantically breaks the ABI for empty final types, since the address
of the subobject may change. The ABI of the whole object should not be
affected.
Fixes#91266Fixes#93069
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
Some modules are leaf modules in the sense that they are not used by any
other part of the headers. These leaf modules are easy to consolidate
since there is no risk to create a cycle. As a result of regrouping
these modules, several missing includes were found and fixed in this
patch.
A comment in `is_constructible.pass.cpp` suggests that Clang is
non-conforming in accepting construction of `const int&` from
`ExplicitTo<int&&>`.
This PR changes the test to expect the standard-conforming behavior,
which makes the test pass on MSVC.
This trait is implemented in C++26 conditionally on the compiler
supporting the __builtin_is_virtual_base_of intrinsic. I believe only
tip-of-trunk Clang currently implements that builtin.
Closes#105432
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
I had originally made some comments in https://reviews.llvm.org/D128214
that were followed when we implemented LWG2762. I don't understand why I
made these comments anymore, but either way it seems like I was wrong
since using `unique_ptr<void>::operator*` should be ill-formed. All
other implementations also make that ill-formed.
We were not declaring `__uses_allocator_construction_args` helper
functions, leading to several valid uses failing to compile. This
patch solves the problem by moving these helper functions into a
struct, which also reduces the amount of redundant SFINAE we need
to perform since most overloads are checking for a cv-qualfied pair.
Fixes#66714
Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
This adds the new std::enable_nonlocking_formatter_optimization trait in
<format>. This trait will be used in std::print to implement the
performance benefits.
Implements parts of
- P3107R5 - Permit an efficient implementation of ``std::print``
The polymorphic_allocator was added in C++17.
This issue was filed in 2022 so well after C++20. This issue adds an
operator==.
Starting with C++20 this adds a compiler generated operator!=. To have
the same behaviour in C++17 and C++20 (and later) a manual operator!= is
defined in C++17.
Implements
- LWG3683 operator== for polymorphic_allocator cannot deduce template
argument in common cases
These operators were deprecated in
P0768R1 Library Support for the Spaceship (Comparison) Operator
This was discovered while investigating the paper's implementation
status.
See [LWG4061](https://cplusplus.github.io/LWG/issue4061) and
[P3341R0](https://wg21.link/p3341r0). Effectively reverts commit
36ce0c3b1e.
`libcxx/test/std/utilities/format/format.functions/bug_81590.compile.pass.cpp`
has a `format` function that unexpectedly takes the
`basic_format_context` by value, which is made ill-formed by LWG4061.
This PR changes the function to take the context by reference.
See [LWG4106](https://cplusplus.github.io/LWG/issue4106) and
[P3341R0](https://wg21.link/p3341r0).
The test coverage for the empty state of `basic_format_args` in
`get.pass.cpp` is to be completely removed, because the
non-default-constructibility is covered in `ctor.pass.cpp`.
https://cplusplus.github.io/CWG/issues/2137.html
This change was previously made as part of
924701311a (#77768) and later reverted in
6e4930c675
This change is still needed because the comment is still true: A
standards-conformant compiler is currently supposed to fail this test.
This also means that any future work on CWG2137 with Clang would not
need to modify the libc++ test suite
GCC 14 has been released a while ago. We've updated the CI to use GCC 14
now. This removes any old annotations in the tests and updates the
documentation to reflect the updated version requirements.
This patch removes many annotations that are not relevant anymore since
we don't support or test back-deploying to macOS < 10.13. It also cleans
up raw usage of target triples to identify versions of dylibs shipped on
prior versions of macOS, and uses the target-agnostic Lit features
instead. Finally, it reorders both the Lit backdeployment features and
the corresponding availability macros in the library in a way that makes
more sense, and reformulates the Lit backdeployment features in terms of
when a version of LLVM was introduced instead of encoding the system
versions on which it hasn't been introduced yet. Although one can be
derived from the other, encoding the negative form is extremely
error-prone.
Fixes#80901
fixes#92676
So right now clang does not like
```
std::expected<std::any, int> e1;
auto e2 = e1;
```
So basically when clang tries to do overload resolution of `auto e2 =
e1;`
It finds
```
expected(const expected&); // 1. This is OK
expected(const expected<_Up, _OtherErr>&) requires __can_convert; // 2. This needs to check its constraints
```
Then in `__can_convert`, one of the check is
```
_Not<is_constructible<_Tp, expected<_Up, _OtherErr>&>>
```
which is checking
```
is_constructible<std::any, expected<_Up, _OtherErr>&>
```
Then it looks at `std::any`'s constructor
```
template < class _ValueType,
class _Tp = decay_t<_ValueType>,
class = enable_if_t< !is_same<_Tp, any>::value && !__is_inplace_type<_ValueType>::value &&
is_copy_constructible<_Tp>::value> >
any(_ValueType&& __value);
```
In the above, `is_copy_constructible<_Tp>` expands to
```
is_copy_constructible<std::expected<std::any, int>>
```
And the above goes back to the original thing we asked : copy the
`std::expected`, which goes to the overload resolution again.
```
expected(const expected&);
expected(const expected<_Up, _OtherErr>&) requires __can_convert;
```
So the second overload results in a logical cycle.
I am not a language lawyer. We could argue that clang should give up on
the second overload which has logical cycle, as the first overload is a
perfect match.
Anyway, the fix in this patch tries to short-circuiting the second
overload's constraint check: that is, if the argument matches exact same
`expected<T, E>`, we give up immediately and let the copy constructor to
deal with it
Try it again. Use the approach suggested by Tim in the LWG thread :
using function default argument SFINAE
- Revert "[libc++] Revert LWG3233 Broken requirements for shared_ptr
converting constructors (#93071)"
- Revert "[libc++] Revert temporary attempt to implement LWG 4110
(#95263)"
- test for default_delete
- Revert "Revert "[libc++] Revert temporary attempt to implement LWG
4110 (#95263)""
- test for NULL
This effort has quite a history:
- This was first attempted in 2022 via bed3240bf7, which broke
std::shared_ptr<T const> and caused the change to be reverted in
9138666f54.
- We then re-attempted landing the change in 276ca87382 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
a54d028895 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
