GCC 15 has added builtins for various C++ type traits that Clang
already had. Since `__has_builtin(...)` now finds these, the #if
branches previously only used for Clang are now used for GCC 15.
However, GCC 15 requires that these builtins only be used in type
aliases, not in template aliases.
For now, just don't use the `__has_builtin(...)` branches under newer
GCC versions, so both 14 and 15 work during the transition. This
can be cleaned up later to use all the GCC 15 builtins available.
Fixed: #137704Fixed: #117319
Currently, built-in `char`/`wchar_t` arrays are assumed to be
null-terminated sequence with the terminator being the last element in
formatting. This doesn't conform to [format.arg]/6.9.
> otherwise, if `decay_t<TD>` is `char_type*` or `const char_type*`,
> initializes value with `static_cast<const char_type*>(v)`;
The standard wording specifies that character arrays are decayed to
pointers. When the null terminator is not the last element or there's no
null terminator (the latter case is UB), libc++ currently produces
different results.
Also fixes and hardens `formatter<CharT[N], CharT>::format` in
`<__format/formatter_string.h>`. These specializations are rarely used.
Fixes#115935. Also checks the preconditions in this case, which fixes
#116570.
This makes it clearer what the functions actually do. As a nice
side-effect it also avoids a function call. If the C++03 header split is
successful we could drop `__get_pair` entirely.
Some code paths normalize ".." and thus don't create the directory. But some execute in a
shell thus requiring the directory to exist to be able to take the parent directory.
This patch normalizes all the `TARGET_SUBDIR` variables to avoid this issue.
After 8fc2538f33 "Reapply '[libc++]
Optimize num_put integral functions' (#131613) (#133572)", including
<locale> in C++03 mode with Debug hardening enabled fails.
This patch fixes that by applying a workaround used elsewhere to
construct errc in C++03 mode.
`__has_feature(modules)` is always true in C++20 and later. Instead of
using that, just disable extension warnings if they're not ignored
through the system header machinery anyways.
We plan to replace the existing mechanism for overriding detection with
one that doesn't require the use of a special section as an alternative
to llvm/llvm-project#120805 which had other downsides.
This change is a pure refactoring that lays the foundation for a
subsequent change that will introduce the new detection mechanism.
That type trait represents whether move-assigning an object is
equivalent to destroying it and then move-constructing a new one from
the same argument. This will be useful in a few places where we may want
to destroy + construct instead of doing an assignment, in particular
when implementing some container operations in terms of relocation.
This is effectively adding a library emulation of P2786R12's
is_replaceable trait, similarly to what we do for trivial relocation.
Eventually, we can replace this library emulation by the real
compiler-backed trait.
This is building towards #129328.
It's the end of an era. The IRC channel was previously where the
community gathered to discuss technical topics but is now a ghost town
where the primary activity is moderators (me) kickbanning the same
individual dozens of times a day for CoC violations and the secondary
activity is telling the occasional person to come to Discord for help.
The number of people engaging on IRC for the community's intended
purposes seems to be roughly one person a month.
So this removes all remaining mentions of IRC from our documentation so
that it no longer appears to be an "official" channel for communicating
with the community. It also removes IRC handles from the various
maintainers lists, since those would stand out as confusing
anachronisms.
The IRC channel topic already recommends people come to the Discord
server. There is no way to "shut down" an IRC channel such that it no
longer exists, so the channel will continue to exist on OFTC, but will
be unmoderated.
(This was previously discussed in https://discourse.llvm.org/c/llvm/5
but some mentions persisted.)
fdsan is Bionic's "File Descriptor Sanitizer". Starting in API 30+, it
aborts this close.pass.cpp test, because it closes the FD belonging to
std::filebuf's FILE*. For `__BIONIC__`, disable that part of the test.
As libc++ has been implementing niebloids as CPOs since LLVM 14 due to
https://reviews.llvm.org/D116570.
Also changes some comments in test files to use the formal term
"algorithm function object".
Closes#118133.
For several releases, we had a section in the release notes that was
called "Upcoming Deprecations and Removals". That section was used to
advertize breaking changes in future releases as opposed to ones in the
current release.
However, the way this section was worded and organized made it unclear
what release these announcements related to. This patch rewords that
section of the release notes to make it less ambiguous and moves items
that aren't done yet (but relate to the ongoing release) to a different
section with a TODO.
I've recently looked at the assembly for `basic_string::find()` and
realized that there were a few branches I didn't expect. It turns out
that we check for null before calling `__constexpr_memchr` in some
cases, which the compiler doesn't optimize away. This is a really
uncommon case though, so I'm not convinced it makes a ton of sense to
optimize for that.
The second case is where `__pos >= __sz`. There, we can instead check
`__pos > __sz`, which the optimizer is able to remove if `__pos == 0`,
which is also a quite common case (basic_string::find(CharT), without an
explicit size parameter).
This breaks the ABI of `flat_{,multi}map::value_compare`, but this type
has only been introduced in LLVM 20, so it should be very unlikely that
we break anybody if we back-port this now.
This patch enhances test readability by inlining standalone tests,
eliminating unnecessary navigation. Additionally, several classes with
ad-hoc names have been renamed for better clarity:
- `A` -> `CharWrapper` as it wraps a char
- `B -> CharTransformer` as it accepts a char `xc` but stores `xc + 1`
- `Storage -> CharUnionStorage` as it stores a union of 2 `char`s.
This patch addresses a follow-up comment from #120909 to inline tests.
There are currently lots of `_LIBCPP_HAS_ASAN` and
`__libcpp_is_constant_evaluated()` checks which aren't needed, since it
is centrally checked inside `__debug_utils/sanitizers.h`.
Flat container adaptors require the iterators of underlying containers
to be random access, and it is required that random access container
iterators must support three-way comparison ([container.reqmts]/39 - /41).
As a result, we should at least avoid testing "containers" with random
access but not three-way comparable iterators for flat container
adaptors.
This patch adds a new class template `three_way_random_access_iterator`
to `test_iterators.h` and fixes some usages of `MinSequenceContainer`
with the new iterators.
The std::advance function has a clear precondition that it can only be
called with a negative distance when a bidirectional iterator is used.
However, prev() and next() don't have such preconditions explicitly,
they inherit it from calling advance().
This patch removes assertions in prev() and next() that were duplicates
of similar ones in advance(), and removes a copy-pasted comment that was
trying to justify the use of _LIBCPP_ASSERT_PEDANTIC but IMO is creating
confusion with little benefit.
This patch refactors the test for std::vector::emplace back to cover new
corner cases, and increase coverage for normal cases as well.
This is building towards #129328.
The `_LIBCPP_DISABLE_AVAILABILITY` macro was removed in afae1a5f32 as an
intended no-op. It turns out that some projects are making use of that
macro to work around a Clang bug with availability annotations that
still exists: https://github.com/llvm/llvm-project/issues/134151.
Since that Clang bug still hasn't been fixed, I feel that we must sill
honor that unfortunate macro until we've figured out how to get rid of
it without breaking code.
We can use the `__is_nothrow_convertible` builtin unconditionally now,
which makes the implementation very simple, so there isn't much of a
need to keep a separate header around.
This makes it easier to build a new Docker image in the CI. Since the
new image is not used automatically it's safe to commit these changes
directly to main. Then use a PR to test the new image.
We're currently adding `bad_function_call::what()` behind an ABI flag,
even though adding it is not an ABI break and can be handled through
availability.
