The helper function `__pair_like_explicit_wknd` is only SFINAE-ed with
`tuple_size<remove_cvref_t<_PairLike>>::value == 2`, but its function
body assumes `std::get` being valid.
Fixes#65620
Thanks to Giuseppe D'Angelo for pointing this out on the cpplang Slack!
The example implementation in https://eel.is/c++draft/string.view.comparison#example-1
was necessary when it was written, in C++17, but in C++20 we don't need that
complexity anymore, because of the reversed candidates that are
synthesized by the compiler.
This removes a lot of code duplication, makes the code simpler and
prepares the terrain for https://reviews.llvm.org/D101206, which will
fix some UB in the node-based containers.
This also allows removing the dependency of list and forward_list on
unique_ptr by using __allocation_guard instead.
Notice that because Holder<Incomplete> is _possible_ to complete, but
_unsafe_ to complete, that means that Holder<Incomplete>* is basically
not an iterator and it's not even safe to ask if
input_iterator<Holder<Incomplete>*> because that _will_ necessarily
complete the type. So it's totally expected that we still cannot safely
ask e.g.
static_assert(std::indirect_unary_predicate<bool(&)(Holder<Incomplete>&),
Holder<Incomplete>*>);
or even
static_assert(!std::indirect_unary_predicate<int, Holder<Incomplete>*>);
This was originally uploaded as https://reviews.llvm.org/D119029 and I
picked it up here as part of the Github PR transition.
Co-authored-by: Arthur O'Dwyer <arthur.j.odwyer@gmail.com>
When we implemented C++20's P0674R1, we didn't enable the part of
P0674R1 that was resolving LWG2070 as a DR. This patch fixes that and
makes sure that we consistently go through the allocator when
constructing and destroying the underlying object in
std::allocate_shared.
Fixes#54365.
This partially reverts commit e30a148b09, which removed the base
template for std::char_traits. That base template had been marked as
deprecated since LLVM 16 and we were planning to remove it in LLVM 18.
However, as explained in the post-commit comments in
https://reviews.llvm.org/D157058, the deprecation mechanism didn't work
as expected. Basically, the deprecation warnings were never shown to
users since libc++ headers are system headers and Clang doesn't show
warnings in system headers.
As a result, this removal came with basically no lead time as far as
users are concerned, which is a poor experience. For this reason, I am
re-introducing the deprecated char_traits specialization until we have a
proper way of phasing it out in a way that is not a surprise for users.
Since we use C++20 to build the dylib, we can use a lambda to do the
first-time initialization instead of emulating std::bind. This should
not change the behavior of the code at all, it merely simplifies it.
This removes a symbol from the dylib, however that symbol was only ever
used inside the dylib so it shouldn't break the ABI for anyone. I
confirmed that by searching for that symbol on the ABI boundary of a
large number of programs and couldn't find any references to that
function.
This "bug" was probably not noticed because it doesn't affect any integer
type we currently support. It requires integers with more than 2x the
size of `unsigned long long`. However, with such types, the algorithm
used to break down the large integer into groups of size `unsigned long long`
didn't work because we rotated in the wrong direction.
For example, the 256 bit number (1 << 255) would yield the wrong answer
when used with the algorithm before this patch.
In particular, note that the current rotation happens to work for 128 bit
integers because it just swaps the halves in this case.
Differential Revision: https://reviews.llvm.org/D134625
Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
The safe mode is in-between the hardened and the debug modes, extending
the checks contained in the hardened mode with certain checks that are
relatively cheap and prevent common sources of errors but aren't
security-critical. Thus, the safe mode trades off some performance for
a wider set of checks, but unlike the debug mode, it can still be used
in production.
Differential Revision: https://reviews.llvm.org/D158823
[libcxx] <experimental/simd> Added internal storage type for class simd/simd_mask
[libcxx] <experimental/simd> Added all constructors of class simd/simd_mask and related tests
[libcxx] <experimental/simd> Added basic simd reference implementation, subscript operators of class simd/simd_mask and related tests
Reviewed By: #libc, philnik
Differential Revision: https://reviews.llvm.org/D144364
This is to fix an error that occurs when the char type is a class type.
Thanks to Yichen Yan for the patch.
Differential Revision: https://reviews.llvm.org/D100005
It's important that the arch directory be included first so that
its header files which interpose on the default include dir
be included instead of the default ones. The clang driver [1] does
this when not building with -nostdinc, the libcxx build should
do the same.
We found this after https://reviews.llvm.org/D154282 when cross
compiling from non Linux to Linux. If the host machine was not
Linux, _LIBCPP_HAS_NO_TIME_ZONE_DATABASE would be defined in
the default include dir __config_site, while it was undefined
in the arch specific one causing build failures.
On GLibc, FreeBSD and macOS systems nl_catd is a pointer type, and
round-tripping this in a variable of ptrdiff_t is not portable.
In fact such a round-trip yields a non-dereferenceable pointer on
CHERI-enabled architectures such as Arm Morello. There pointers (and
therefore intptr_t) are twice the size of ptrdiff_t, which means casting
to ptrdiff_t strips the high (metadata) bits (as well as a hidden pointer
validity bit).
Since catalog is now guaranteed to be the same size or larger than nl_catd,
we can store all return values safely and the shifting workaround from
commit 0c68ed006d should not be needed
anymore (this is also not portable to CHERI systems on since shifting a
valid pointer right will create a massively out-of-bounds pointer that
may not be representable).
This can be fixed by using intptr_t which should be the same type as
ptrdiff_t on all currently supported architectures.
See also: https://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2028
Differential Revision: https://reviews.llvm.org/D134420
Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
After many years of using the really old std::pair ABI which did not yet
have a trivial copy constructor, FreeBSD 14 and later will finally get
rid of it. Only use the old ABI for FreeBSD 13 and earlier.
Note: on the FreeBSD side, we will bump our libc++.so version for this,
and keep an old compatibility library in a separate package.
Differential Revision: https://reviews.llvm.org/D126462
This is the first step to implement time zone support in libc++. This
adds the complete tzdb_list class and a minimal tzdb class. The tzdb
class only contains the version, which is used by reload_tzdb.
Next to these classes it contains documentation and build system support
needed for time zone support. The code depends on the IANA Time Zone
Database, which should be available on the platform used or provided by
the libc++ vendors.
The code is labeled as experimental since there will be ABI breaks
during development; the tzdb class needs to have the standard headers.
Implements parts of:
- P0355 Extending <chrono> to Calendars and Time Zones
Addresses:
- LWG3319 Properly reference specification of IANA time zone database
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D154282
This brings most of the enable_ifs in libc++ to the same style. It also has the nice side-effect of reducing the size of names of these symbols, since the depedent return type is shorter.
Reviewed By: #libc, ldionne
Spies: ldionne, libcxx-commits
Differential Revision: https://reviews.llvm.org/D157787
This brings most of the enable_ifs in libc++ to the same style.
Reviewed By: #libc, ldionne
Spies: ldionne, libcxx-commits
Differential Revision: https://reviews.llvm.org/D157753
Both Clang and GCC always define __BYTE_ORDER__, so there is no need to test the byte order a million different ways.
Reviewed By: #libc, ldionne
Spies: ldionne, libcxx-commits, krytarowski
Differential Revision: https://reviews.llvm.org/D158216
This is to prevent a GCC warning (
https://github.com/llvm/llvm-project/issues/65132). It looks like
`__at_first` is always assigned before it's used, but all other member
variables of this struct are initialized in the constructor, so there is
no reason not to initialize `__at_first` as well.
Differential Revision: https://reviews.llvm.org/D159249
This allows including once_flag directly from <__locale> instead of
depending on all of <mutex>, which requires threading. In turn, this
makes it easier to support locales on platforms without threading.
Drive-by change: clang-format once_flag.h and use _LIBCPP_HIDE_FROM_ABI
Differential Revision: https://reviews.llvm.org/D155487
We only support Clang on windows, so this code path is never taken.
Reviewed By: #libc, Mordante
Spies: Mordante, libcxx-commits
Differential Revision: https://reviews.llvm.org/D158230
This was mention in D150044 and D154995 that this would be useful.
This addresses the last review coment of D150044.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D156019
`__assign_view__` is declared as a noexcept function in `libcxx/include/__filesystem/path.h` however internally it calls `std::basic_string<char>::basic_string<char>(std::string_view)` which is not a noexcept function this may lead to a `std::terminate()` call when allocation of a new string fails.
Fixes : https://github.com/llvm/llvm-project/issues/64858
Reviewed By: Mordante, #libc
Differential Revision: https://reviews.llvm.org/D158826
When `__locale_dir/locale_base_api/locale_guard.h is` compiled independently, as it is when it's in its own clang module, it fails to compile due to `locale_t` being undefined. It needs to include `__locale` to get that, instead of just `clocale`.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D158669