This documentation aims to make it cleare how the libc++ pre-commit CI
works. For libc++ developers and other LLVM projects whose changes can
affect libc++.
This was discusses with @aaron.ballman as a follow on some unclearities
for the Clang communitee how the libc++ pre-commit CI works.
Note some parts depend on patches under review as commented in the
documentation.
Reviewed By: ldionne, #libc, philnik
Differential Revision: https://reviews.llvm.org/D133249
It looks like we forgot to set the FTM when adding constexpr vector support.
Reviewed By: ldionne, #libc
Spies: libcxx-commits, arichardson
Differential Revision: https://reviews.llvm.org/D137729
This mirrors what we have done in the classic algorithms
Reviewed By: ldionne, #libc
Spies: libcxx-commits
Differential Revision: https://reviews.llvm.org/D137186
This doesn't affect our ABI because `std::string::substr()` isn't in the dylib and the mangling of `substr() const` and `substr() const&` are different.
Reviewed By: ldionne, Mordante, var-const, avogelsgesang, #libc
Spies: arphaman, huixie90, libcxx-commits
Differential Revision: https://reviews.llvm.org/D131668
Claim some tasks for formatting and mark some parts as complete, which
was missed in the commits completing the task.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D137014
No code changes, but only increased the range in the tests.
Completes:
- LWG3273. Specify weekday_indexed to range of [0, 7]
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D137015
This commit deprecates <experimental/memory_resource> since we now ship the non-experimental
version of it. Per the libc++ policy [1], we are deprecating the experimental feature in
upcoming LLVM 16 and will remove it entirely in LLVM 18.
[1]: https://libcxx.llvm.org/DesignDocs/ExperimentalFeatures.html#id4
Reviewed By: ldionne, #libc
Spies: EricWF, libcxx-commits
Differential Revision: https://reviews.llvm.org/D136245
We've said that we'll remove `std::function` from C++03 in LLVM 16, so we might as well do it now before we forget.
Reviewed By: ldionne, #libc, Mordante
Spies: jloser, Mordante, libcxx-commits
Differential Revision: https://reviews.llvm.org/D135868
Partially implements:
- P1361 Integration of chrono with text formatting
- P2372 Fixing locale handling in chrono formatters
- LWG3270 Parsing and formatting %j with durations
Completes:
- P1650R0 std::chrono::days with 'd' suffix
- LWG3262 Formatting of negative durations is not specified
- LWG3314 Is stream insertion behavior locale dependent when Period::type is micro?
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D134742
LWG-3539 was already implemented but not marked as done.
LWG-3567 is implemented in this commit.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D112368
Implements:
- P2291R3 Add Constexpr Modifiers to Functions to_chars and from_chars for
Integral Types in <charconv> Header
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D131317
This patch is the rebase and squash of three earlier patches.
It supersedes all three of them.
- D47111: experimental monotonic_buffer_resource.
- D47358: experimental pool resources.
- D47360: Copy std::experimental::pmr to std::pmr.
The significant difference between this patch and the-sum-of-those-three
is that this patch does not add `std::experimental::pmr::monotonic_buffer_resource`
and so on. This patch simply adds the C++17 standard facilities, and
leaves the `std::experimental` namespace entirely alone.
Differential Revision: https://reviews.llvm.org/D89057
Implementing the paper
P2291R3 Add Constexpr Modifiers to Functions to_chars and from_chars for
Integral Types in <charconv> Header
Gives issues in language versions prior to C++17. As suggested in
D131855 disable the code prior to C++17. This removes libc++'s
extension.
Reviewed By: ldionne, #libc_vendors, #libc, philnik
Differential Revision: https://reviews.llvm.org/D133216
implement `std::ranges::basic_istream_view` and `std::views::istream`. Although the view itself is constexpr,
the constructor argument is a base class std::istream where its ctor/dtor are not constexpr. So no tests are performed in
constexpr
Differential Revision: https://reviews.llvm.org/D133317
This concept is introduced in P2286, but was implemented in libc++
before. This implementation was used in the library internally. This
implementation lacked the resolution of LWG3636. The original formatter
had a non-const member function that wasn't trivial to make a const
member. The recent parser improvements made this member a const member
in preparation of LWG3636.
Note LWG3636 isn't voted in. Its status is Ready. P2286's concept has
been written as-if LWG3636 is accepted and refers to that LWG issue.
Updates some tests make format a const member function and removes a
tests that's mainly a duplicate of the formattable concept test.
Implements
- LWG3636 formatter<T>::format should be const-qualified
Implements parts of
- P2286R8 Formatting Ranges
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D134110
This is a breaking change. If you were passing one of those three runtimes
in LLVM_ENABLE_PROJECTS, you need to start passing them in LLVM_ENABLE_RUNTIMES
instead. The runtimes in LLVM_ENABLE_RUNTIMES will start being built using
the "bootstrapping build" instead, which means that they will be built
using the just-built Clang. This is usually what you wanted anyway.
If you were using LLVM_ENABLE_PROJECTS=all with the explicit goal of
building these three runtimes, you can now use LLVM_ENABLE_RUNTIMES=all
and these runtimes will be built using the bootstrapping build.
NOTE: This is a re-application of 887b8bd733ea which had been reverted
in 6b03a4fea0b4 because it broke the Sphinx documentation publishers.
The Sphinx documentation publishers have now been moved to using
the runtimes build, so this should not be an issue anymore.
Differential Revision: https://reviews.llvm.org/D132480
This patch enables libc++ build as shared library in all combinations of ASCII/EBCDIC and 32-bit/64-bit variants. In particular it introduces:
# ASCII version of libc++ named as libc++_a.so
# Script to rename DLL name inside the generated side deck
# Various names for dataset members where DLL libraries and their side decks will reside
# Add the following options:
- LIBCXX_SHARED_OUTPUT_NAME
- LIBCXX_ADDITIONAL_COMPILE_FLAGS
- LIBCXX_ADDITIONAL_LIBRARIES
- LIBCXXABI_ADDITIONAL_COMPILE_FLAGS
- LIBCXXABI_ADDITIONAL_LIBRARIES
**Background and rational of this patch**
The linker on z/OS creates a list of exported symbols in a file called side deck. The list contains the symbol name as well as the name of the DLL which implements the symbol. The name of the DLL depends on what is specified in the -o command line option. If it points to a USS file, than the DLL name in the side deck will be the USS file name. If it points to a member of a dataset then the DLL name in the side deck is the member name.
If CMake could deal with z/OS datasets we could use -o that points to a dataset member name, but this does not seem to work so we have to produce a USS file as the DLL and then copy the content of the produced side deck to a dataset as well as rename the USS file name in the side deck to a dataset member name that corresponds to that DLL.
Reviewed By: muiez, SeanP, ldionne, #libc, #libc_abi
Differential Revision: https://reviews.llvm.org/D118503
Implement LWG 3629, by making lookup for make_error_code and
make_error_condition only consider names found by ADL. This is achieved
by adding a block scope using-declaration for a function that will be
found by unqualified lookup, preventing unqualified lookup from
continuing to enclosing scopes (the class scope, then enclosing
namespaces). The function named by the using declaration is not
viable, so overload resolution must select a candidate found by ADL.
This fixes https://github.com/llvm/llvm-project/issues/57614
Differential Revision: https://reviews.llvm.org/D134943
Now that all jobs have moved over to the new style of Lit configuration,
we can remove all traces of the legacy testing configuration system.
This includes:
- Cache settings that are not honored or useful anymore
- Several CMake options that were only useful in the context of the
legacy Lit configuration system
- A bunch of Python support code that is not used anymore
- The legacy lit.cfg.in files themselves
Differential Revision: https://reviews.llvm.org/D134650
The new version is a lot simpler and has less option which were not
used. This uses the CSV files as generated by D133127 as input data.
The current Python script has more features but uses a simple "grep"
making the output less accurate:
- Conditionally included header are always included. This is an issue
since part of our includes are unneeded transitive includes. Based on
the language version they may be omitted. The script however always
includes them.
- Includes in comments are processed as-if they are includes. This is an
issue when comments explain how certain data is generated; of course
there are digraphs which the script omits.
This implementation uses Clang's --trace-includes to generate the includes
per header. This means the input of the generation script always has the
real list of includes.
Libc++ is moving from large monolithic Standard headers to more fine
grained headers. For example, algorithm includes every header in
`__algorithm`. Adding all these detail headers in the graph makes the
output unusable. Instead it only shows the Standard headers. The
transitive includes of the detail headers are parsed and "attributed" to
the Standard header including them. This gives an accurate include graph
without the unneeded clutter. Note that this graph is still big.
This changes fixes the cyclic dependency issue with the previous version
of the tool so the markers and its documentation is removed.
Since the input has no cycles the CI test is removed.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D134188
This is a breaking change. If you were passing one of those three runtimes
in LLVM_ENABLE_PROJECTS, you need to start passing them in LLVM_ENABLE_RUNTIMES
instead. The runtimes in LLVM_ENABLE_RUNTIMES will start being built using
the "bootstrapping build" instead, which means that they will be built
using the just-built Clang. This is usually what you wanted anyway.
If you were using LLVM_ENABLE_PROJECTS=all with the explicit goal of
building these three runtimes, you can now use LLVM_ENABLE_RUNTIMES=all
and these runtimes will be built using the bootstrapping build.
Differential Revision: https://reviews.llvm.org/D132480
In https://llvm.org/D56913, we added an emulation for the __atomic_always_lock_free
compiler builtin when compiling in Freestanding mode. However, the emulation
did (and could not) give exactly the same answer as the compiler builtin,
which led to a potential ABI break for e.g. enum classes.
After speaking to the original author of D56913, we agree that the correct
behavior is to instead always use the compiler builtin, since that provides
a more accurate answer, and __atomic_always_lock_free is a purely front-end
builtin which doesn't require any runtime support. Furthermore, it is
available regardless of the Standard mode (see https://godbolt.org/z/cazf3ssYY).
However, this patch does constitute an ABI break. As shown by https://godbolt.org/z/1eoex6zdK:
- In LLVM <= 11.0.1, an atomic<enum class with 1 byte> would not contain a lock byte.
- In LLVM >= 12.0.0, an atomic<enum class with 1 byte> would contain a lock byte.
This patch breaks the ABI again to bring it back to 1 byte, which seems
like the correct thing to do.
Fixes#57440
Differential Revision: https://reviews.llvm.org/D133377
It seems these includes are still provided by the sub headers, so it only
removes the duplicates.
There is no change in the list of includes, but the change affects the
modular build. By not having the includes in the top-level header the
module map has changed. This uncovers missing includes in the tests
and missing exports in the module map. This causes the huge amount of
changes in the patch.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D133252
This change implements the C library dependent portions of P0482R6
(char8_t: A type for UTF-8 characters and strings (Revision 6)) by
declaring std::c8rtomb() and std::mbrtoc8() in the <cuchar> header
when implementations are provided by the C library as specified by
WG14 N2653 (char8_t: A type for UTF-8 characters and strings
(Revision 1)) as adopted for C23.
A _LIBCPP_HAS_NO_C8RTOMB_MBRTOC8 macro is defined by the libc++ __config
header unless it is known that the C library provides these functions
in the current compilation mode. This macro is used for testing purposes
and may be of use to libc++ users. At present, the only C library known
to implement these functions is GNU libc as of its 2.36 release.
Reviewed By: ldionne
Differential Revision: https://reviews.llvm.org/D130946
During the discussion on the SG-10 mailinglist regarding the format
feature-test macros voted in during the last plenary it turns out libc++
can't mark the format feature-test macro as implemented.
According to
https://isocpp.org/std/standing-documents/sd-6-sg10-feature-test-recommendations#__cpp_lib_format
the not yet implemented paper
P1361R2 Integration of chrono with text formatting
affects the feature test macro.
Note that P1361R2 doesn't mention the feature-test macro nor is there an
LWG-issue to address the issue. The reporter of the issue didn't recall
where this requirement exactly has been decided.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D133271
Adding `[[nodiscard]]` to functions is a conforming extension and done extensively in the MSVC STL.
Reviewed By: ldionne, EricWF, #libc
Spies: #libc_vendors, cjdb, mgrang, jloser, libcxx-commits
Differential Revision: https://reviews.llvm.org/D128267
This defines a new policy for removal of transitive includes.
The goal of the policy it to make it relatively easy to remove
headers when needed, but avoid breaking developers using and
vendors shipping libc++.
The method used is to guard transitive includes based on the
C++ language version. For the upcoming C++23 we can remove
headers when we want, but for other language versions we try
to keep it to a minimum.
In this code the transitive include of `<chrono>` is removed
since D128577 introduces a header cycle between `<format>`
and `<chrono>`. This cycle is indirectly required by the
Standard. Our cycle dependency tool basically is a grep based
tool, so it needs some hints to ignore cycles. With the input
of our transitive include tests we can create a better tool.
However that's out of the scope of this patch.
Note the flag `_LIBCPP_REMOVE_TRANSITIVE_INCLUDES` remains
unchanged. So users can still opt-out of transitives includes
entirely.
Reviewed By: #libc, ldionne, philnik
Differential Revision: https://reviews.llvm.org/D132284
Implements:
- LWG3721 Allow an arg-id with a value of zero for width in std-format-spec
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D130649
