Instead of providing full specializations of `hash` for every arithmetic
type, this moves the implementation to a base class, which is
specialized via `enable_if`s instead.
This reverts commit c861fe8a71e64f3d2108c58147e7375cd9314521.
Unfortunately, this use of hidden visibility attributes causes
user-defined specializations of standard-library types to also be marked
hidden by default, which is incorrect. See discussion thread on #131156.
...and also reverts the follow-up commits:
Revert "[libc++] Add explicit ABI annotations to functions from the block runtime declared in <__functional/function.h> (#140592)"
This reverts commit 3e4c9dc299c35155934688184319d391b298fff7.
Revert "[libc++] Make ABI annotations explicit for windows-specific code (#140507)"
This reverts commit f73287e623a6c2e4a3485832bc3e10860cd26eb5.
Revert "[libc++][NFC] Replace a few "namespace std" with the correct macro (#140510)"
This reverts commit 1d411f27c769a32cb22ce50b9dc4421e34fd40dd.
This patch introduces `_LIBCPP_{BEGIN,END}_EXPLICIT_ABI_ANNOTATIONS`,
which allow us to have implicit annotations for most functions, and just
where it's not "hide_from_abi everything" we add explicit annotations.
This allows us to drop the `_LIBCPP_HIDE_FROM_ABI` macro from most
functions in libc++.
This avoids instantiating multiple classes, reducing compile times. This
patch also introduces `__underyling_type_t` for internal use, similar to
other type traits.
This has multiple benefits:
- There is a single instance of our hash function, reducing object file
size
- The hash implementation isn't instantiated in every TU anymore,
reducing compile times
- Behind an ABI configuration macro it would be possible to salt the
hash
This set usage of operator& instead of std::addressof seems not be easy
to "abuse". Some seem easy to misuse, like basic_ostream::operator<<,
trying to do that results in compilation errors since the `widen`
function is not specialized for the hijacking character type. Hence
there are no tests.
Currently we're using quite different internal names for the
`std::invoke` family of type traits. This adds a layer around the
current implementation to make it easier to understand when it is used
and makes it easier to define multiple implementations of it.
We can define some of these aliases without having to include the system
<stddef.h> and there doesn't seem to be much of a reason we shouldn't do
it this way.
The implementation of std::hash for unsigned long makes the (correct)
assumption that size_t is at least as large as unsigned long. If that
were not the case on a platform, the implementation of std::hash for
unsigned long would be absolutely terrible. Add a static assertion to
document that assumption.
Currently, the library-internal feature test macros are only defined if
the feature is not available, and always have the prefix
`_LIBCPP_HAS_NO_`. This patch changes that, so that they are always
defined and have the prefix `_LIBCPP_HAS_` instead. This changes the
canonical use of these macros to `#if _LIBCPP_HAS_FEATURE`, which means
that using an undefined macro (e.g. due to a missing include) is
diagnosed now. While this is rather unlikely currently, a similar change
in `<__configuration/availability.h>` caught a few bugs. This also
improves readability, since it removes the double-negation of `#ifndef
_LIBCPP_HAS_NO_FEATURE`.
The current patch only touches the macros defined in `<__config>`. If
people are happy with this approach, I'll make a follow-up PR to also
change the macros defined in `<__config_site>`.
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.
These headers have become very small by using compiler builtins, often
containing only two declarations. This merges these headers, since
there doesn't seem to be much of a benefit keeping them separate.
Specifically, `is_{,_nothrow,_trivially}{assignable,constructible}` are
kept and the `copy`, `move` and `default` versions of these type traits
are moved in to the respective headers.
We forward declare `reference_wrapper` in multiple places already. This
moves the declaration to the canonical place and removes unnecessary
includes of `__functional/reference_wrapper.h`.
This patch runs clang-format on all of libcxx/include and libcxx/src, in
accordance with the RFC discussed at [1]. Follow-up patches will format
the benchmarks, the test suite and remaining parts of the code. I'm
splitting this one into its own patch so the diff is a bit easier to
review.
This patch was generated with:
find libcxx/include libcxx/src -type f \
| grep -v 'module.modulemap.in' \
| grep -v 'CMakeLists.txt' \
| grep -v 'README.txt' \
| grep -v 'libcxx.imp' \
| grep -v '__config_site.in' \
| xargs clang-format -i
A Git merge driver is available in libcxx/utils/clang-format-merge-driver.sh
to help resolve merge and rebase issues across these formatting changes.
[1]: https://discourse.llvm.org/t/rfc-clang-formatting-all-of-libc-once-and-for-all
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
We already have a clang-tidy check for making sure that `_LIBCPP_HIDE_FROM_ABI` is on free functions. This patch extends this to class members. The places where we don't check for `_LIBCPP_HIDE_FROM_ABI` are classes for which we have an instantiation in the library.
Reviewed By: ldionne, Mordante, #libc
Spies: jplehr, mikhail.ramalho, sstefan1, libcxx-commits, krytarowski, miyuki, smeenai
Differential Revision: https://reviews.llvm.org/D142332
This change is almost fully mechanical. The only interesting change is in `generate_feature_test_macro_components.py` to generate `_LIBCPP_STD_VER >=` instead. To avoid churn in the git-blame this commit should be added to the `.git-blame-ignore-revs` once committed.
Reviewed By: ldionne, var-const, #libc
Spies: jloser, libcxx-commits, arichardson, arphaman, wenlei
Differential Revision: https://reviews.llvm.org/D143962
- Add missing _LIBCPP_HIDE_FROM_ABI
- Implement inline functions in the class to simplify the code
- Add missing `const` to `operator()`
- Move _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK to the usual location for function attributes
Differential Revision: https://reviews.llvm.org/D143668
As explained in a comment in https://reviews.llvm.org/D134124, we tried
landing this unconditionally but this actually bit some users who were
sharing std::unordered_map across an ABI boundary. This shows that the
ABI break is not benign and it should be guarded behind ABI v2.
Differential Revision: https://reviews.llvm.org/D143688
Rename the `__tuple` directory in libc++ headers to `__tuple_dir`
to avoid file collision when installing. Historically, `__tuple` has
been a file and it has been replaced by a directory
in 2d52c6bfae801b016dd3627b8c0e7c4a99405549. Replacing a regular file
with a directory (or more importantly, the other way around when
downgrading) is not universally supported. Since this is an internal
header, its actual name should not matter, so just rename it to avoid
problems.
Differential Revision: https://reviews.llvm.org/D139270
As PR56606 stated, the current implementation of CityHash in libc++
would drop some bits unintentionally. Cast the 32bit int to the 64bit
int to avoid this happened.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D134124
This commit reverts 5aaefa51 (and also partly 7f285f48e77 and b6d75682f9,
which were related to the original commit). As landed, 5aaefa51 had
unintended consequences on some downstream bots and didn't have proper
coverage upstream due to a few subtle things. Implementing this is
something we should do in libc++, however we'll first need to address
a few issues listed in https://reviews.llvm.org/D106124#3349710.
Differential Revision: https://reviews.llvm.org/D120683
libc++ has started splicing standard library headers into much more
fine-grained content for maintainability. It's very likely that outdated
and naive tooling (some of which is outside of LLVM's scope) will
suggest users include things such as <__ranges/access.h> instead of
<ranges>, and Hyrum's law suggests that users will eventually begin to
rely on this without the help of tooling. As such, this commit
intends to protect users from themselves, by making it a hard error for
anyone outside of the standard library to include libc++ detail headers.
Differential Revision: https://reviews.llvm.org/D106124
The NFC part of D116809. We still want to enforce this in CI,
but the mechanism for that is still to-be-determined.
Differential Revision: https://reviews.llvm.org/D116809
Some embedded platforms do not wish to support the C library functionality
for handling wchar_t because they have no use for it. It makes sense for
libc++ to work properly on those platforms, so this commit adds a carve-out
of functionality for wchar_t.
Unfortunately, unlike some other carve-outs (e.g. random device), this
patch touches several parts of the library. However, despite the wide
impact of this patch, I still think it is important to support this
configuration since it makes it much simpler to port libc++ to some
embedded platforms.
Differential Revision: https://reviews.llvm.org/D111265
Clang used to support [[nodebug]] everywhere except on typedefs. Since
we don't support such old Clangs anymore, we can get rid of _LIBCPP_NODEBUG_TYPE
in favour of always using _LIBCPP_NODEBUG.
Differential Revision: https://reviews.llvm.org/D108996
This started as fixing a typo in a ADDITIONAL_COMPILE_FLAGS directive
which turned out to uncover a few places where we warned about signedness
changes.
As a fly-by fix, this updates the various __advance overloads
for style consistency.
Differential Revision: https://reviews.llvm.org/D106372
