__has_keyword is almost not used anymore. There are only two cases. One can be replaced by __has_builtin and the other seems entirely redundant, so we can remove the definition.
Reviewed By: #libc, Mordante
Spies: Mordante, libcxx-commits
Differential Revision: https://reviews.llvm.org/D158215
This avoids having to add `_LIBCPP_ENUM_VIS`, since that is handled through `type_visibility` and GCC always makes the visibility of enums default. It also fixes and missing `_LIBCPP_EXPORTED_FROM_ABI` on classes when using Clang.
Reviewed By: ldionne, #libc
Spies: libcxx-commits
Differential Revision: https://reviews.llvm.org/D153658
The hardened mode is intended to only include security-critical,
relatively low-overhead checks that are intended to be usable in
production. By default, assertions are excluded from this mode.
Differential Revision: https://reviews.llvm.org/D155866
This makes __threading_support contain nothing but the base threading
API provided by the system.
Differential Revision: https://reviews.llvm.org/D155458
`_LIBCPP_ENABLE_ASSERTIONS` was used to enable the "safe" mode in
libc++. Libc++ now provides the hardened mode and the debug mode that
replace the safe mode.
For backward compatibility, enabling `_LIBCPP_ENABLE_ASSERTIONS` now
enables the hardened mode. Note that the hardened mode provides
a narrower set of checks than the previous "safe" mode (only
security-critical checks that are performant enough to be used in
production).
Differential Revision: https://reviews.llvm.org/D154997
This patch only adds new configuration knobs -- the actual assertions
will be added in follow-up patches.
Differential Revision: https://reviews.llvm.org/D153902
There are discussions about different ways of implementing `stop_token` to make it more performant
mark `stop_token` as experimental to allow us to change the design before it is shipped
Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
Differential Revision: https://reviews.llvm.org/D154700
POSIX allows certain macros to exist with generic names (i.e. refresh(), move(), and erase()) to exist in `curses.h` which conflict with functions found in std::filesystem, among others. This patch undefs the macros in question and adds them to LIBCPP_PUSH_MACROS and LIBCPP_POP_MACROS.
Reviewed By: #libc, philnik, ldionne
Differential Revision: https://reviews.llvm.org/D147356
This revision is a part of a series of patches extending AddressSanitizer C++ container overflow detection capabilities by adding annotations, similar to those existing in `std::vector`, to `std::string` and `std::deque` collections. These changes allow ASan to detect cases when the instrumented program accesses memory which is internally allocated by the collection but is still not in-use (accesses before or after the stored elements for `std::deque`, or between the size and capacity bounds for `std::string`).
The motivation for the research and those changes was a bug, found by Trail of Bits, in a real code where an out-of-bounds read could happen as two strings were compared via a std::equals function that took `iter1_begin`, `iter1_end`, `iter2_begin` iterators (with a custom comparison function). When object `iter1` was longer than `iter2`, read out-of-bounds on `iter2` could happen. Container sanitization would detect it.
This revision introduces annotations for `std::deque`. Each chunk of the container can now be annotated using the `__sanitizer_annotate_double_ended_contiguous_container` function, which was added in the rG1c5ad6d2c01294a0decde43a88e9c27d7437d157. Any attempt to access poisoned memory will trigger an ASan error. Although false negatives are rare, they are possible due to limitations in the ASan API, where a few (usually up to 7) bytes before the container may remain unpoisoned. There are no false positives in the same way as with `std::vector` annotations.
This patch only supports objects (deques) that use the standard allocator. However, it can be easily extended to support all allocators, as suggested in the D146815 revision.
Furthermore, the patch includes the addition of the `is_double_ended_contiguous_container_asan_correct` function to `libcxx/test/support/asan_testing.h`. This function can be used to verify whether a `std::deque` object has been correctly annotated.
Finally, the patch extends the unit tests to verify ASan annotations (added LIBCPP_ASSERTs).
If a program is compiled without ASan, all helper functions will be no-ops. In binaries with ASan, there is a negligible performance impact since the code from the change is only executed when the deque container changes in size and it’s proportional to the change. It is important to note that regardless of whether or not these changes are in use, every access to the container's memory is instrumented.
If you have any questions, please email:
- advenam.tacet@trailofbits.com
- disconnect3d@trailofbits.com
Reviewed By: #libc, philnik
Differential Revision: https://reviews.llvm.org/D132092
This doesn't change the selection, but it expands the conditions to
add comments and make it clearer what's happening. It also removes a
-Wundef instance when we checked __ARM_ARCH_7K__ >= 2 without checking
that it is defined in the first place.
Differential Revision: https://reviews.llvm.org/D153413
In particular, this ensures that it is used for Objective-C and
Objective-C++, since we have a few files that get detected as that.
Differential Revision: https://reviews.llvm.org/D153289
These macros are always defined identically, so we can simplify the code a bit by merging them.
Reviewed By: ldionne, #libc
Spies: libcxx-commits, krytarowski, smeenai
Differential Revision: https://reviews.llvm.org/D152652
This checks whether a pointer is within a range, even during constant evaluation. This allows running optimized code paths during constant evaluation, instead of falling back to the general-purpose implementation all the time. This is also a central place for comparing unrelated pointers, which is technically UB.
Reviewed By: ldionne, #libc
Spies: libcxx-commits
Differential Revision: https://reviews.llvm.org/D143327
Back in 2020 [1], we went very close to enabling Filesystem on MSVC
by disabling int128_t, but decided to wait because MSVC support
for int128_t was supposed to come shortly after. Since it's not
there yet, I propose turning off int128_t support by default on MSVC.
This will make <filesystem> available by default on MSVC, and most
importantly will open the possibility for changing
LIBCXX_ENABLE_FILESYSTEM to mean "the system doesn't have support
for a filesystem" instead of simply "don't build the std::filesystem
library", which is what I'm really after with this change.
In a way, this is a resurection of D91139.
[1]: https://reviews.llvm.org/D91139#2429595
Differential Revision: https://reviews.llvm.org/D134912
This is just to test that the PSTL works with parallelization. This is not supposed to be a production-ready backend.
Reviewed By: ldionne, #libc
Spies: EricWF, arichardson, libcxx-commits
Differential Revision: https://reviews.llvm.org/D150284
This revision is a part of a series of patches extending AddressSanitizer C++ container overflow detection capabilities by adding annotations, similar to those existing in std::vector, to std::string and `std::deque` collections. These changes allow ASan to detect cases when the instrumented program accesses memory which is internally allocated by the collection but is still not in-use (accesses before or after the stored elements for `std::deque`, or between the size and capacity bounds for `std::string`).
The motivation for the research and those changes was a bug, found by Trail of Bits, in a real code where an out-of-bounds read could happen as two strings were compared via a std::equals function that took `iter1_begin`, `iter1_end`, `iter2_begin` iterators (with a custom comparison function). When object `iter1` was longer than `iter2`, read out-of-bounds on `iter2` could happen. Container sanitization would detect it.
This revision introduces annotations for `std::deque`. Each chunk of the container can now be annotated using the `__sanitizer_annotate_double_ended_contiguous_container` function, which was added in the rG1c5ad6d2c01294a0decde43a88e9c27d7437d157. Any attempt to access poisoned memory will trigger an ASan error. Although false negatives are rare, they are possible due to limitations in the ASan API, where a few (usually up to 7) bytes before the container may remain unpoisoned. There are no false positives in the same way as with `std::vector` annotations.
This patch only supports objects (deques) that use the standard allocator. However, it can be easily extended to support all allocators, as suggested in the D146815 revision.
Furthermore, the patch includes the addition of the `is_double_ended_contiguous_container_asan_correct` function to libcxx/test/support/asan_testing.h. This function can be used to verify whether a `std::deque` object has been correctly annotated.
Finally, the patch extends the unit tests to verify ASan annotations (added LIBCPP_ASSERTs).
If a program is compiled without ASan, all helper functions will be no-ops. In binaries with ASan, there is a negligible performance impact since the code from the change is only executed when the deque container changes in size and it’s proportional to the change. It is important to note that regardless of whether or not these changes are in use, every access to the container's memory is instrumented.
Reviewed By: #libc, philnik
Spies: vitalybuka, hans, mikhail.ramalho, Enna1, #sanitizers, philnik, libcxx-commits
Differential Revision: https://reviews.llvm.org/D132092
The code has been quite ready for a while now and there are no more ABI
breaking papers. So this is a good time to mark the feature as stable.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D150802
To make sure all member functions that require it are marked `_LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION` I compared the output of `objdump --syms lib/libc++.1.0.dylib` before and after, ignoring addresses.
Reviewed By: #libc, ldionne
Spies: Mordante, libcxx-commits, ldionne, arichardson, mstorsjo
Differential Revision: https://reviews.llvm.org/D150896
During the ISO C++ Committee meeting plenary session the C++23 Standard
has been voted as technical complete.
This updates the reference to c++2b to c++23 and updates the __cplusplus
macro.
Note since we use clang-tidy 16 a small work-around is needed. Clang
knows -std=c++23 but clang-tidy not so for now force the lit compiler
flag to use -std=c++2b instead of -std=c++23.
Reviewed By: #libc, philnik, jloser, ldionne
Differential Revision: https://reviews.llvm.org/D150795
This removes the need for a custom libc++ build to have a basic set of PSTL algorithms.
Reviewed By: ldionne, #libc
Spies: miyuki, libcxx-commits, arichardson
Differential Revision: https://reviews.llvm.org/D149624
This revision is a part of a series of patches extending AddressSanitizer C++ container overflow detection capabilities by adding annotations, similar to those existing in std::vector, to std::string and `std::deque` collections. These changes allow ASan to detect cases when the instrumented program accesses memory which is internally allocated by the collection but is still not in-use (accesses before or after the stored elements for `std::deque`, or between the size and capacity bounds for `std::string`).
The motivation for the research and those changes was a bug, found by Trail of Bits, in a real code where an out-of-bounds read could happen as two strings were compared via a std::equals function that took `iter1_begin`, `iter1_end`, `iter2_begin` iterators (with a custom comparison function). When object `iter1` was longer than `iter2`, read out-of-bounds on `iter2` could happen. Container sanitization would detect it.
This revision introduces annotations for `std::deque`. Each chunk of the container can now be annotated using the `__sanitizer_annotate_double_ended_contiguous_container` function, which was added in the rG1c5ad6d2c01294a0decde43a88e9c27d7437d157. Any attempt to access poisoned memory will trigger an ASan error. Although false negatives are rare, they are possible due to limitations in the ASan API, where a few (usually up to 7) bytes before the container may remain unpoisoned. There are no false positives in the same way as with `std::vector` annotations.
This patch only supports objects (deques) that use the standard allocator. However, it can be easily extended to support all allocators, as suggested in the D146815 revision.
Furthermore, the patch includes the addition of the `is_double_ended_contiguous_container_asan_correct` function to libcxx/test/support/asan_testing.h. This function can be used to verify whether a `std::deque` object has been correctly annotated.
Finally, the patch extends the unit tests to verify ASan annotations (added LIBCPP_ASSERTs).
If a program is compiled without ASan, all helper functions will be no-ops. In binaries with ASan, there is a negligible performance impact since the code from the change is only executed when the deque container changes in size and it’s proportional to the change. It is important to note that regardless of whether or not these changes are in use, every access to the container's memory is instrumented.
Reviewed By: #libc, philnik
Spies: mikhail.ramalho, Enna1, #sanitizers, philnik, libcxx-commits
Differential Revision: https://reviews.llvm.org/D132092
This was contributed ~10 years ago, but we don't officially support it
and I am not aware of any bot testing it, so this has likely rotten to
the point where it is unusable.
Differential Revision: https://reviews.llvm.org/D138680
This adds a list of attributes which can be pretty to be able to reject attributes which were introduced in a later C++ standard.
Fixes#61196
Reviewed By: Mordante, #libc
Spies: mikhail.ramalho, jdoerfert, libcxx-commits
Differential Revision: https://reviews.llvm.org/D145508
AppleClang 1403 has some bugs that prevent std::source_location from
working properly on it. Consequently, we XFAILed the unit test for
source_location with that compiler. However, we should also avoid
advertising that the feature is supported on that compiler, otherwise
our feature-test macros lie. This was noticed to break Boost.Asio
when building with a recent libc++ and AppleClang 14.0.3.
rdar://106863087
Differential Revision: https://reviews.llvm.org/D146837
It was only used in one place, and it seems entirely valid to use
constexpr unconditionally in that location.
Note that a different change was attempted, i.e. using consteval
unconditionally. However, this led to http://llvm.org/PR60709.
Differential Revision: https://reviews.llvm.org/D145700
The AIX linker does not support linking against libc++ if it exports symbols are redefined within compiled code.
Differential Revision: https://reviews.llvm.org/D140675
Clang wants to enable this flag by default, but libc++ isn't working with it yet.
Reviewed By: Mordante, #libc, #libc_abi, EricWF
Spies: libcxx-commits, arichardson
Differential Revision: https://reviews.llvm.org/D144667
This check flags code which uses `_LIBCPP_STD_VER` the wrong way, or tries to use `__cplusplus`. It flags cases where we use `_LIBCPP_STD_VER >` instead of `_LIBCPP_STD_VER >=` and where wrong values are used (e.g. `_LIBCPP_STD_VER >= 24`).
Reviewed By: ldionne, #libc
Spies: libcxx-commits
Differential Revision: https://reviews.llvm.org/D144261
Currently, there are bugs in Clang's intrinsics for type traits when
handling Objective-C++ `id` (e.g. in `add_pointer`). As a temporary
workaround, don't use these intrinsics in the Objective-C++ mode.
Differential Revision: https://reviews.llvm.org/D145186
Other macros that disable parts of the library are named `_LIBCPP_HAS_NO_WHATEVER`.
Reviewed By: ldionne, Mordante, #libc
Spies: libcxx-commits, smeenai
Differential Revision: https://reviews.llvm.org/D143163
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
It causes mysterious memory leaks when comparing std::string, see GitHub
Issue #60709 and the code review.
> All supported compilers support `consteval`, so there is no more need for the macro.
>
> Reviewed By: ldionne, Mordante, #libc
>
> Spies: libcxx-commits
>
> Differential Revision: https://reviews.llvm.org/D143489
This reverts commit aaef3b82f4.
All supported compilers support `consteval`, so there is no more need for the macro.
Reviewed By: ldionne, Mordante, #libc
Spies: libcxx-commits
Differential Revision: https://reviews.llvm.org/D143489
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
We renamed the `_LIBCPP_CONSTEXPR_` a while ago. This matches the change for `_LIBCPP_EXPLICIT_`.
Reviewed By: Mordante, #libc
Spies: libcxx-commits
Differential Revision: https://reviews.llvm.org/D143165
Other macros that disable parts of the library are named `_LIBCPP_HAS_NO_WHATEVER`.
Reviewed By: ldionne, Mordante, #libc
Spies: libcxx-commits
Differential Revision: https://reviews.llvm.org/D143164
When support for declaring the c8rtomb() and mbrtoc8() functions within the
std namespace was added in commit 7e7013c5d4,
internal glibc macros were used to determine if C2X extensions are enabled.
Specifically, a check for whether `__GLIBC_USE` is defined and whether
`__GLIBC_USE(ISOC2X)` is non-0 was added. `__GLIBC_USE` is an internal
detail of the glibc implementation that may be changed or removed in the
future potentially leading to inconsistency or compilation failures. This
change removes the use of the internal glibc macro to avoid such problems.
Unfortunately, without another mechanism to determine if C2X extensions are
enabled, this removal will result in inconsistent declarations of the
c8rtomb() and mbrtoc8() functions; when C++ char8_t support is not enabled, but
C2X extensions are, these functions will be declared in the global namespace
but not in the std namespace. This situation will improve when C23 support
is finalized and the check can be re-implemented using `__STDC_VERSION__`.
