We have multiple macros for different Windows. However, most of them
don't actually define different things. We can condense the macros to
- `_WIN32` directly if it only depends on windows, or
- `_LIBCPP_MSVCRT`
This patch drops `_LIBCPP_MSVCRT_LIKE` and `_LIBCPP_WIN32API`, since
they are equivalent to `_WIN32`.
The macro is already used in `<__configuration/attributes.h>` and just
happens to work because we include both headers.
`<__configuration/utility.h>` seems like the obvious place to put the
macros.
As discussed in https://gcc.gnu.org/PR114298 - GCC and MSVC STL
implemented P2711R1 as a DR. This PR does the same for libc++.
Co-authored-by: A. Jiang <de34@live.cn>
We always define either `_LIBCPP_HAS_C_ATOMIC_IMP` or
`_LIBCPP_HAS_GCC_ATOMIC_IMP`, so we can remove any special handling of
not having an `<atomic>` header.
We've updated the supported AppleClang version, so we can drop those
workarounds now.
This also removes `__is_referenceable_v`, since it's no longer used.
This patch introduces `_LIBCPP_{BEGIN/END}_EXPLICIT_ABI_ANNOTATIONS` and
marks everything within an
`_LIBCPP_{BEGIN,END}_UNVERSIONED_NAMESPACE_STD` (and any derivatives
like `_LIBCPP_{BEGIN,END}_NAMESPACE_STD`) implicitly by default. This
allows us to drop `_LIBCPP_HIDE_FROM_ABI` in most of the code base,
except for functions which shouldn't be `_LIBCPP_HIDE_FROM_ABI`.
This patch doesn't remove any `_LIBCPP_HIDE_FROM_ABI`s, since we have
over 13k of them in the code base. Actually dropping them will happen
over some time to avoid too many merge conflicts.
This is another step in splitting up `<__config>` to make it easier to
understand what's going on and have logically separate parts of the
configuration properly separated.
Introduce CMake option `LIBCXX_HAS_C11_THREAD_API` that explicitly
instructs libc++ to use C11 threads. Make sure
`_LIBCPP_HAS_THREAD_API_C11` is defined properly in the
`<__config_site>` and interacts correctly with platform-based
auto-selection of thread API when it's not explicitly set.
`_LIBCPP_FREESTANDING` isn't used and it is unclear what libc++'s
strategy is going to be for implementing freestanding at the moment.
Therefore, remove the macro.
This patch moves all macros which expand to attributes into a detail
header, including the relatively complex visibility and ABI-hiding
attributes. This also adds sections for attributes that are important to
not be ignored. At the bottom there is a catch-all section for
attributes which can safely be ignored and are only important for the
quality of implementation.
Using `_LIBCPP_WEAK` doesn't give us anything that using `[[gnu::weak]]`
directly couldn't, so we can just expand the macro.
As a drive-by this also refactors `_LIBCPP_OVERRIDABLE_FUNCTION`.
Introducing the notion of a minimum header version has multiple
benefits. It allows us to merge a bunch of ABI macros into a single one.
This makes configuring the library significantly easier, since, for a
stable ABI, you only need to know which version you started distributing
the library with, instead of checking which ABI flags have been
introduced at what point. For platforms which have a moving window of
the minimum version a program has been compiled against, this also makes
it simple to remove symbols from the dylib when they can't be used by
any program anymore.
The `#warning` causes diagnostics if system headers include deprecated
headers. #168041 will add a way to deprecated headers properly, which
then also interacts nicely with system header suppression.
Currently, there are no diagnostics issued when including a deprecated
header, since the diagnostic is issued inside a system header. This
patch fixes that by using `#warning` instead, which also simplifies the
implementation of the deprecation warnings.
Add a new CMake variable, `LIBCXX_ASSERTION_SEMANTIC`, that largely
mirrors `LIBCXX_HARDENING_MODE`, except that it also supports a
special value `hardening_dependent` that indicates the semantic will be
selected based on the hardening mode in effect:
- `fast` and `extensive` map to `quick_enforce`;
- `debug` maps to `enforce`.
Define `_LIBCPP_HAS_C8RTOMB_MBRTOC8` to `1` if compiling with clang.
Some tests involving functionality from `uchar.h`/`cuchar` fail when the
platform or the supporting C library does not provide support for the
corresponding features. These have been xfailed.
This patch will enable the adoption of newer picolibc versions.
Libc++ hardening went through several iterations, sometimes within a
single release. However, some folks in the wild have picked up these
macros that were either public at some point or that were used
temporarily on `main`, and unfortunately those are now ignored.
This can lead to some users thinking they enable hardening when in
reality they don't, which is a pretty big deal. This patch simply checks
various old hardening-related macros and ensures that they are not set,
which will catch such misuse.
Assertion semantics closely mimic C++26 Contracts evaluation semantics.
This brings our implementation closer in line with C++26 Library Hardening
(one particular benefit is that using the `observe` semantic makes adopting
hardening easier for projects).
Unlike `verbose_abort`, this function merely logs the error but does not
terminate execution. It is intended to make it possible to implement the
`observe` semantic for Hardening.
Assertion semantics closely mimic C++26 Contracts evaluation semantics.
This brings our implementation closer in line with C++26 Library
Hardening (one particular benefit is that using the `observe` semantic
makes adopting hardening easier for projects).
For these annotations to do anything you need `-Wthread-safety`, in
which case users most likely enable them anyways. This avoids that users
have to explictly define a macro just to use the feature they already
had to opt-in to.
