This patch removes the two-level backend dispatching mechanism we had in
the PSTL. Instead of selecting both a PSTL backend and a PSTL CPU
backend, we now only select a top-level PSTL backend. This greatly
simplifies the PSTL configuration layer.
While this patch technically removes some flexibility from the PSTL
configuration mechanism because CPU backends are not considered
separately, it opens the door to a much more powerful configuration
mechanism based on chained backends in a follow-up patch.
This is a step towards overhauling the PSTL dispatching mechanism.
Picolibc does not provide the clock_gettime function nor the "rt" library.
check_library_exists was invalidly detecting the "rt" library due to cmake issue
present, when cross-compiling[1]. This resulted with "chrono.cpp" trying to link
to the "rt" library and following error:
unable to find library from dependent library specifier: rt
[1] https://gitlab.kitware.com/cmake/cmake/-/issues/18121
Installs the source files of the experimental libc++ modules. These
source files (.cppm) are used by the Clang to build the std and
std.compat modules.
The design of this patch is based on a discussing in SG-15 on
12.12.2023. (SG-15 is the ISO C++ Tooling study group):
- The modules are installed at a location, that is not known to build
systems and compilers.
- Next to the library there will be a module manifest json file.
This json file contains the information to build the module from the
libraries sources. This information includes the location where the
sources are installed. @ruoso supplied the specification of this json
file.
- If possible, the compiler has an option to give the location of the
module manifest file
(https://github.com/llvm/llvm-project/pull/76451).
Currently there is no build system support, but it expected to be added
in the future.
Fixes: https://github.com/llvm/llvm-project/issues/73089
Revert "Revert #76246 and #76083"
This reverts commit 5c150e7eeba9db13cc65b329b3c3537b613ae61d.
Adds a small fix that should properly disable the tests on Windows.
Unfortunately the original poster has not provided feedback and the
original patch did not fail in the LLVM CI infrastructure.
Modules are known to fail on Windows due to non compliance of the
C library. Currently not having this patch prevents testing on other
platforms.
These cause test build failures on Windows.
This reverts the following commits:
57ca74843586c9a93c425036c5538aae0a2cfa60
d06ae33ec32122bb526fb35025c1f0cf979f1090
This removes the entire modules testing infrastructure.
The current infrastructure uses CMake to generate the std and std.compat
module. This requires quite a bit of plumbing and uses CMake. Since
CMake introduced module support in CMake 3.26, modules have a higher
CMake requirement than the rest of the LLVM project. (The LLVM project
requires 3.20.) The main motivation for this approach was how libc++
generated its modules. Every header had its own module partition. This
was changed to improve performance and now only two modules remain. The
code to build these can be manually crafted.
A followup patch will reenable testing modules, using a different
approach.
I recently came across LIBCXXABI_USE_LLVM_UNWINDER and was surprised to
notice it was disabled by default. Since we build libunwind by default
and ship it in the LLVM toolchain, it would seem to make sense that
libc++ and libc++abi rely on libunwind for unwinding instead of using
the system-provided unwinding library (if any).
Most importantly, using the system unwinder implies that libc++abi is
ABI compatible with that system unwinder, which is not necessarily the
case. Hence, it makes a lot more sense to instead default to using the
known-to-be-compatible LLVM unwinder, and let vendors manually select a
different unwinder if desired.
As a follow-up change, we should probably apply the same default to
compiler-rt.
Differential Revision: https://reviews.llvm.org/D150897Fixes#77662
rdar://120801778
This patch adds a configuration of the libc++ test suite that enables
optimizations when building the tests. It also adds a new CI
configuration to exercise this on a regular basis. This is added in the
context of [1], which requires building with optimizations in order to
hit the bug.
[1]: https://github.com/llvm/llvm-project/issues/68552
And add a check in the python script that the binary given to `--qemu`
actually exists. Otherwise you get a generic Python error:
```
# .---command stderr------------
# | Traceback (most recent call last):
# | File "/home/david.spickett/modules-llvm-project/libcxx/utils/qemu_baremetal.py", line 70, in <module>
# | exit(main())
# | File "/home/david.spickett/modules-llvm-project/libcxx/utils/qemu_baremetal.py", line 66, in main
# | os.execvp(qemu_commandline[0], qemu_commandline)
# | File "/usr/lib/python3.8/os.py", line 568, in execvp
# | _execvpe(file, args)
# | File "/usr/lib/python3.8/os.py", line 610, in _execvpe
# | raise last_exc
# | File "/usr/lib/python3.8/os.py", line 601, in _execvpe
# | exec_func(fullname, *argrest)
# | FileNotFoundError: [Errno 2] No such file or directory
# `-----------------------------
# error: command failed with exit status: 1
```
When it tries to run the entire command later.
For the builder, it's only ever going to use qemu-system-arm so error at
config time if it's not there.
When we use the -nostdlib++ flag, we don't need to explicitly link
against compiler-rt, since the compiler already links against it by
default. This simplifies the flags that we need to use when building
with Clang and GCC, and opens the door to further simplifications since
most platforms won't need to detect whether libgcc and libgcc_s are
supported anymore.
Furthermore, on platforms where -nostdlib++ is used, this patch prevents
manually linking compiler-rt *before* other system libraries. For
example, Apple platforms have several compiler-rt symbols defined in
libSystem.dylib. If we manually link against compiler-rt, we end up
overriding the default link order preferred by the compiler and
potentially using the symbols from the clang-provided libclang_rt.a
library instead of the system provided one.
Note that we don't touch how libunwind links against compiler-rt when it
builds the .so/.a because libunwind currently doesn't use -nodefaultlibs
and we want to avoid rocking the boat too much.
rdar://119506163
There are a few drive-by fixes:
- Since the combination RTTI disabled and exceptions enabled do not
work, this combination is prohibited.
- A small NFC in any fixing clang-tidy.
The code in the Buildkite configuration is prepared for using the std
module. There are more fixes needed for that configuration which will be
done in a separate commit.
This patch actually runs the tests for picolibc behind an emulator,
removing a few workarounds and increasing coverage.
Differential Revision: https://reviews.llvm.org/D155521
Picolibc is a C Standard Library that is commonly used in embedded
environments. This patch adds initial support for this configuration
along with pre-commit CI. As of this patch, the test suite only builds
the tests and nothing is run. A follow-up patch will make the test suite
actually run the tests.
Differential Revision: https://reviews.llvm.org/D154246
1. Instead of using individual "boolean" macros, have an "enum" macro
`_LIBCPP_HARDENING_MODE`. This avoids issues with macros being
mutually exclusive and makes overriding the hardening mode within a TU
more straightforward.
2. Rename the safe mode to debug-lite.
This brings the code in line with the RFC:
https://discourse.llvm.org/t/rfc-hardening-in-libc/73925Fixes#65101
Android's librt and libpthread functionality is part of libc.{a,so}
instead. The atomic APIs are part of the compiler-rt builtins archive.
Android does have libdl.
Android's libc.so has `__cxa_thread_atexit_impl` starting in API 23, and
the oldest supported API is 21, so continue using feature detection for
that API.
These settings need to be declared explicitly for the sake of the fuzzer
library's custom libc++ build `add_custom_libcxx`. That macro builds
libc++ using `-DCMAKE_TRY_COMPILE_TARGET_TYPE=STATIC_LIBRARY`, which
breaks the feature detection.
Add a new test mode that enables the hardened mode in combination with
ABI-breaking changes (only bounded iterators currently) and reenable the
bounded iterator tests for `span` and `string_view`.
I could probably break this commit into more pieces.
---
This patch adds libc++ support for Android L (Android 5.0+) and up,
tested using the Android team's current compiler, a recent version of
the AOSP sysroot, and the x86[-64] Android Emulator.
CMake and Lit Configuration:
Add runtimes/cmake/android/Arch-${ARCH}.cmake files that configure CMake
to cross-compile to Android without using CMake's built-in NDK support
(which only works with an actual packaged NDK).
Add libcxx/cmake/caches/AndroidNDK.cmake that builds and tests libc++
(and libc++abi) for Android. This file configures libc++ to match what
the NDK distributes, e.g.:
- libc++_shared.so (includes libc++abi objects, there is no
libc++abi.so). libunwind is linked statically but not exported.
- libc++_static.a (does not include libc++abi) and libc++abi.a
- `std::__ndk1` namespace
- All the libraries are built with `__ANDROID_API__=21`, even when they
are linked to something targeting a higher API level.
(However, when the Android LLVM team builds these components, they do
not use these CMake cache files. Instead they use Python scripts to
configure the builds. See
https://android.googlesource.com/toolchain/llvm_android/.)
Add llvm-libc++[abi].android-ndk.cfg.in files that test the Android
NDK's libc++_shared.so. These files can target old or new Android
devices. The Android LLVM team uses these test files to test libc++ for
both arm/arm64 and x86/x86_64 architectures.
The Android testing mode works by setting %{executor} to adb_run.py,
which uses `adb push` and `adb shell` to run tests remotely. adb_run.py
always runs tests as the "shell" user even on an old emulator where "adb
unroot" doesn't work. The script has workarounds for old Android
devices. The script uses a Unix domain socket on the host
(--job-limit-socket) to restrict concurrent adb invocations. Compiling
the tests is a major part of libc++ testing run-time, so it's desirable
to exploit all the host cores without overburdening the test devices,
which can have far fewer cores.
BuildKite CI:
Add a builder to run-buildbot, `android-ndk-*`, that uses Android Clang
and an Android sysroot to build libc++, then starts an Android emulator
container to run tests.
Run the emulator and an adb server in a separate Docker container
(libcxx-ci-android-emulator), and create a separate Docker image for
each emulator OS system image. Set ADB_SERVER_SOCKET to connect to the
container's adb server. Running the only adb server inside the container
makes cleanup more reliable between test runs, e.g. the adb client
doesn't create a `~/.android` directory and the adb server can be
restarted along with the emulator using docker stop/run. (N.B. The
emulator insists on connecting to an adb server and will start one
itself if it can't connect to one.)
The suffix to the android-ndk-* job is a label that concisely specifies
an Android SDK emulator image. e.g.:
- "system-images;android-21;default;x86" ==> 21-def-x86
- "system-images;android-33;google_apis;x86_64" ==> 33-goog-x86_64
Fixes: https://github.com/llvm/llvm-project/issues/69270
Differential Revision: https://reviews.llvm.org/D139147
We support GCC 13, which supports the flag. This allows simplifying the
CMake logic around the use of -nostdlib++. Note that there are other
places where we don't assume -nostdlib++ yet in the build, but this
patch is intentionally trying to be small because this part of our CMake
is pretty tricky.
On Apple platforms, we always support the -nostdlib++ flag. Hence, it is
not necessary to manually link against system libraries. In fact, doing
so causes us to link against libSystem explicitly, which messes up with
the order of libraries we should use. Indeed:
Before patch, using the system unwinder (LIBCXXABI_USE_LLVM_UNWINDER = OFF)
===========================================================================
$ otool -L lib/{libc++.1.dylib,libc++abi.1.dylib,libunwind.1.dylib}
lib/libc++.1.dylib:
@rpath/libc++.1.dylib
/usr/lib/libSystem.B.dylib
@rpath/libc++abi.1.dylib
lib/libc++abi.1.dylib:
@rpath/libc++abi.1.dylib
/usr/lib/libSystem.B.dylib
lib/libunwind.1.dylib:
@rpath/libunwind.1.dylib
/usr/lib/libSystem.B.dylib
After patch, using the system unwinder (LIBCXXABI_USE_LLVM_UNWINDER = OFF)
===========================================================================
$ otool -L lib/{libc++.1.dylib,libc++abi.1.dylib,libunwind.1.dylib}
lib/libc++.1.dylib:
@rpath/libc++.1.dylib
@rpath/libc++abi.1.dylib
/usr/lib/libSystem.B.dylib
lib/libc++abi.1.dylib:
@rpath/libc++abi.1.dylib
/usr/lib/libSystem.B.dylib
lib/libunwind.1.dylib:
@rpath/libunwind.1.dylib
/usr/lib/libSystem.B.dylib
Before patch, with the LLVM unwinder (LIBCXXABI_USE_LLVM_UNWINDER = ON)
=======================================================================
$ otool -L lib/{libc++.1.dylib,libc++abi.1.dylib,libunwind.1.dylib}
lib/libc++.1.dylib:
@rpath/libc++.1.dylib
/usr/lib/libSystem.B.dylib
@rpath/libc++abi.1.dylib
@rpath/libunwind.1.dylib
lib/libc++abi.1.dylib:
@rpath/libc++abi.1.dylib
/usr/lib/libSystem.B.dylib
@rpath/libunwind.1.dylib
lib/libunwind.1.dylib:
@rpath/libunwind.1.dylib
/usr/lib/libSystem.B.dylib
After patch, with the LLVM unwinder (LIBCXXABI_USE_LLVM_UNWINDER = ON)
======================================================================
$ otool -L lib/{libc++.1.dylib,libc++abi.1.dylib,libunwind.1.dylib}
lib/libc++.1.dylib:
@rpath/libc++.1.dylib
@rpath/libc++abi.1.dylib
@rpath/libunwind.1.dylib
/usr/lib/libSystem.B.dylib
lib/libc++abi.1.dylib:
@rpath/libc++abi.1.dylib
@rpath/libunwind.1.dylib
/usr/lib/libSystem.B.dylib
lib/libunwind.1.dylib:
@rpath/libunwind.1.dylib
/usr/lib/libSystem.B.dylib
As we can see, libSystem appears before the just-built libraries before
the patch, which causes the libunwind.dylib bundled in libSystem.dylib
to be used instead of the just-built libunwind.dylib.
We didn't notice the issue until recently when I tried to update the
macOS CI builders to macOS 13.5, where it is necessary to use the right
libunwind library (the exact reason still needs to be investigated).
This gets rid of the separate parameter enable_modules_lsv in favor of
adding a named option to the enable_modules parameter. The patch also
removes the getModuleFlag helper, which was just a really complicated
way of hardcoding "none".
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
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
The std module can be tested in the generic C++23 build. This removes the
special module build.
Note it is possible to enable modules automatically in CMake, but that
would fail in the "parts disabled" builds; they have not been properly
been converted to modules yet.
Depends on D157625
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D157744
This fixes some missing #ifndef and implements the header restrictions
in the modules script.
Depends on D158192
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D158330
The building of the std module has been moved from `params.py` and
`dsl.py` to a `lit.local.cfg` for the entire test suite. In theory this
change allows testing modules in most configurations, except:
- combined with clang modules
- C++ versions that don't support the std module
Currently only C++23 with all parts enabled works.
C++26 is expected to work properly with CMake 3.27. That versions of CMake
knows how to invoke clang using C++26.
The parts disabled modi of libc++ have not been modularized yet.
It still is the goal that in the future CMake will be able to do the work
done in `lit.local.cfg`. Doing this in CMake would require a more mature
libc++ implementation.
Thanks a lot to @ldionne for giving hints how to enable modules in a
`lit.local.cfg`.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D157625
With the underlying bug fixed the work-around should no longer be
needed.
Reviewed By: #libc, philnik
Differential Revision: https://reviews.llvm.org/D157779
The Apple.cmake cache wasn't set up properly, so we wouldn't enable
the libdispatch backend by default on Apple platforms. This patch
fixes the issue and adds a test.
We also need to make various drive-by fixes:
- Drop the usage of std::vector in libdispatch.h to avoid changing
the transitive includes only on Apple platforms.
- Fix includes
- Use __construct at since construct_at is unavailable in C++17
- Get rid of the (unused) __get_memory_resource function since that
adds a back-deployment requirement and we don't use it right now.
- Fix bugs in the chunking logic around boundary conditions.
Differential Revision: https://reviews.llvm.org/D155649
`_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
The patch is based on D144994.
D151030 added the module definitions for the module std.
This patch wires in the module and enables the basic testing.
Some notable features are missing:
- There is no test that libc++ can be fully imported as a module.
- This lacks the parts for the std.compat module.
- The module is not shipped with libc++.
Implements parts of
- P2465R3 Standard Library Modules std and std.compat
Reviewed By: ldionne, aaronmondal, #libc
Differential Revision: https://reviews.llvm.org/D151814
libcxxrt is only used on FreeBSD and the FreeBSD CMake cache already
sets LIBCXX_ENABLE_NEW_DELETE_DEFINITIONS to ON, as it should. This
avoids defining LIBCXX_ENABLE_NEW_DELETE_DEFINITIONS redundantly in
a place where it doesn't belong.
Differential Revision: https://reviews.llvm.org/D152971
LIBCXX_ENABLE_FILESYSTEM should represent whether the platform has
support for a filesystem, not just whether we support <filesystem>.
This patch slightly generalizes the setting to also encompass whether
we provide <fstream>, since that only makes sense when a filesystem is
supported.
Differential Revision: https://reviews.llvm.org/D152168
Clang has been updated to support C++26, this adds the same support for
libc++. At the moment C++23 and C++26 are identical. During the next
plenary in June the first C++26 papers will be voted on.
Note like Clang this patch uses C++26 is the internal part and C++2c in
the user visible part.
Depends on D150795
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D151026
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
