When P0883R2 was initially implemented in D103769 #pragma clang deprecated didn't exist yet.
We also forgot to cleanup usages in libc++ itself.
This takes care of both.
Differential Revision: https://reviews.llvm.org/D115995
The library is always build using C++20 so these guards are not needed.
Reviewed By: #libc, Quuxplusone, ldionne
Differential Revision: https://reviews.llvm.org/D115644
We had previously been using a different workaround for pretending that
we were inside a system header, however it had some undesirable effects
on dependency parsing for build systems, as explained in [1].
This patch changes the workaround to use `#pragma GCC system_header`,
which shouldn't suffer from the same issue. Unfortunately, it is a lot
more verbose. The issue is that `#pragma GCC system_header` is ignored
when we are inside a source file, so we have to create a header just for
the sake of using it. IMO this seems like an artificial restriction
without much benefit, but investigating that is a different story.
For now, this should at least solve build system problems at the
cost of some readability.
[1]: https://reviews.llvm.org/D95972#3178968
Differential Revision: https://reviews.llvm.org/D115334
Microsoft would like to contribute its implementation of floating-point to_chars to libc++. This uses the impossibly fast Ryu and Ryu Printf algorithms invented by Ulf Adams at Google. Upstream repos: https://github.com/microsoft/STL and https://github.com/ulfjack/ryu .
Licensing notes: MSVC's STL is available under the Apache License v2.0 with LLVM Exception, intentionally chosen to match libc++. We've used Ryu under the Boost Software License.
This patch contains minor changes from Jorg Brown at Google, to adapt the code to libc++. He verified that it works in Google's Linux-based environment, but then I applied more changes on top of his, so any compiler errors are my fault. (I haven't tried to build and test libc++ yet.) Please tell me if we need to do anything else in order to follow https://llvm.org/docs/DeveloperPolicy.html#attribution-of-changes .
Notes:
* libc++'s integer charconv is unchanged (except for a small refactoring). MSVC's integer charconv hasn't been tuned for performance yet, so you're not missing anything.
* Floating-point from_chars isn't part of this patch because Jorg found that MSVC's implementation (derived from our CRT's strtod) was slower than Abseil's. If you're unable to use Abseil or another implementation due to licensing or technical considerations, Microsoft would be delighted if you used MSVC's from_chars (and you can just take it, or ask us to provide a patch like this). Ulf is also working on a novel algorithm for from_chars.
* This assumes that float is IEEE 32-bit, double is IEEE 64-bit, and long double is also IEEE 64-bit.
* I have added MSVC's charconv tests (the whole thing: integer/floating from_chars/to_chars), but haven't adapted them to libcxx's harness at all. (These tests will be available in the microsoft/STL repo soon.)
* Jorg added int128 codepaths. These were originally present in upstream Ryu, and I removed them from microsoft/STL purely for performance reasons (MSVC doesn't support int128; Clang on Windows does, but I found that x64 intrinsics were slightly faster).
* The implementation is split into 3 headers. In MSVC's STL, charconv contains only Microsoft-written code. xcharconv_ryu.h contains code derived from Ryu (with significant modifications and additions). xcharconv_ryu_tables.h contains Ryu's large lookup tables (they were sufficiently large to make editing inconvenient, hence the separate file). The xmeow.h convention is MSVC's for internal headers; you may wish to rename them.
* You should consider separately compiling the lookup tables (see https://github.com/microsoft/STL/issues/172 ) for compiler throughput and reduced object file size.
* See https://github.com/StephanTLavavej/llvm-project/commits/charconv for fine-grained history. (If necessary, I can perform some rebase surgery to show you what Jorg changed relative to the microsoft/STL repo; currently that's all fused into the first commit.)
Differential Revision: https://reviews.llvm.org/D70631
There's a lot of history behind this, so here's a summary:
1. I stopped forcing -fPIC when building the runtimes in 30f305efe2,
before the LLVM 9 release back in 2019.
2. Someone complained that libc++.a couldn't be used in shared libraries
built without -fPIC (http://llvm.org/PR43604) since the LLVM 9 release.
This had been caused by my removal of -fPIC when building libc++.a in (1).
3. I suggested two ways of fixing the issue, the first being to force
-fPIC back unconditionally (http://llvm.org/D104328), and the second
being to specify that option explicitly when building the LLVM release
(http://llvm.org/D104327). We converged on the first solution.
4. I landed D104328, which forced building the runtimes with -fPIC.
This was included in the LLVM 13.0 release.
5. People complained about that and requested that we be able to
customize this setting (basically we should have done the second
solution).
This patch makes it such that the LLVM release script will specifically
ask for building with -fPIC using CMAKE_POSITION_INDEPENDENT_CODE,
however by default the runtimes will not force that option onto users.
This patch has the unintended effect that Clang and the LLVM libraries
(not only the runtime ones like libc++) will also be built with -fPIC
in the release. It would be better if we could specify that -fPIC is to
be used only when building the runtimes, however this is left as a
future improvement. The release should probably be using a bootstrapping
build and passing those options to the stage that builds the runtimes
only, see https://reviews.llvm.org/D112748 for that change.
Differential Revision: https://reviews.llvm.org/D110261
Microsoft would like to contribute its implementation of floating-point to_chars to libc++. This uses the impossibly fast Ryu and Ryu Printf algorithms invented by Ulf Adams at Google. Upstream repos: https://github.com/microsoft/STL and https://github.com/ulfjack/ryu .
Licensing notes: MSVC's STL is available under the Apache License v2.0 with LLVM Exception, intentionally chosen to match libc++. We've used Ryu under the Boost Software License.
This patch contains minor changes from Jorg Brown at Google, to adapt the code to libc++. He verified that it works in Google's Linux-based environment, but then I applied more changes on top of his, so any compiler errors are my fault. (I haven't tried to build and test libc++ yet.) Please tell me if we need to do anything else in order to follow https://llvm.org/docs/DeveloperPolicy.html#attribution-of-changes .
Notes:
* libc++'s integer charconv is unchanged (except for a small refactoring). MSVC's integer charconv hasn't been tuned for performance yet, so you're not missing anything.
* Floating-point from_chars isn't part of this patch because Jorg found that MSVC's implementation (derived from our CRT's strtod) was slower than Abseil's. If you're unable to use Abseil or another implementation due to licensing or technical considerations, Microsoft would be delighted if you used MSVC's from_chars (and you can just take it, or ask us to provide a patch like this). Ulf is also working on a novel algorithm for from_chars.
* This assumes that float is IEEE 32-bit, double is IEEE 64-bit, and long double is also IEEE 64-bit.
* I have added MSVC's charconv tests (the whole thing: integer/floating from_chars/to_chars), but haven't adapted them to libcxx's harness at all. (These tests will be available in the microsoft/STL repo soon.)
* Jorg added int128 codepaths. These were originally present in upstream Ryu, and I removed them from microsoft/STL purely for performance reasons (MSVC doesn't support int128; Clang on Windows does, but I found that x64 intrinsics were slightly faster).
* The implementation is split into 3 headers. In MSVC's STL, charconv contains only Microsoft-written code. xcharconv_ryu.h contains code derived from Ryu (with significant modifications and additions). xcharconv_ryu_tables.h contains Ryu's large lookup tables (they were sufficiently large to make editing inconvenient, hence the separate file). The xmeow.h convention is MSVC's for internal headers; you may wish to rename them.
* You should consider separately compiling the lookup tables (see https://github.com/microsoft/STL/issues/172 ) for compiler throughput and reduced object file size.
* See https://github.com/StephanTLavavej/llvm-project/commits/charconv for fine-grained history. (If necessary, I can perform some rebase surgery to show you what Jorg changed relative to the microsoft/STL repo; currently that's all fused into the first commit.)
Differential Revision: https://reviews.llvm.org/D70631
-Wformat-nonliteral was turned on in https://reviews.llvm.org/D112927,
however we forgot to apply some __format__ attributes in Linux specific
code paths, which led to warnings when building on Linux. This patch
addresses that oversight.
Differential Revision: https://reviews.llvm.org/D113876
This patch has been tested in D70631, but it should be reviewed
separately.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D114248
The aim of this patch is to resolve the missing `table_size` symbol (see reduced test case). That const variable is declared and defined in //libcxx/include/locale//; however, the test case suggests that the symbol is missing. This is due to a C++ pitfall (highlighted [[ https://quuxplusone.github.io/blog/2020/09/19/value-or-pitfall/ | here ]]). In summary, assigning the reference of `table_size` doesn't enforce the const-ness and expects to find `table_size` in the DLL. The fix is to use `constexpr` or have an out-of-line definition in the src (for consistency).
Differential Revision: https://reviews.llvm.org/D110647
std::atomic is, for the most part, just a thin veneer on top of compiler
builtins. Hence, it should be available even when threads are not available
on the system, and in fact there has been requests for such support.
This patch:
- Moves __libcpp_thread_poll_with_backoff to its own header so it can
be used in <atomic> when threads are disabled.
- Adds a dummy backoff policy for atomic polling that doesn't know about
threads.
- Adjusts the <atomic> feature-test macros so they are provided even when
threads are disabled.
- Runs the <atomic> tests when threads are disabled.
rdar://77873569
Differential Revision: https://reviews.llvm.org/D114109
We've stopped doing it in libc++ for a while now because these names
would end up rotting as we move things around and copy/paste stuff.
This cleans up all the existing files so as to stop the spreading
as people copy-paste headers around.
However, whether applications rely on the std::bad_function_call vtable
being in the dylib is still controlled by the ABI macro, since changing
that would be an ABI break.
Also separate preprocessor definitions for whether to use a key function
and whether to use a `bad_function_call`-specific `what` message
(`what` message is mandated by [LWG2233](http://wg21.link/LWG2233)).
Differential Revision: https://reviews.llvm.org/D92397
Even if building cxx_static in itself doesn't actually link in the
requested unwinder, add a synthetic dependency so that building
cxx_static makes sure that the unwinder that was requested to be used
also gets built.
This makes sure that tests (when run with just a plain "ninja check-cxx")
actually use the newly built unwinder, as intended.
Differential Revision: https://reviews.llvm.org/D113467
When wide characters are supported libc++ manually translates a
`narrow non-breaking space` and a `non-breaking space` to a space.
This behaviour wasn't available when wide characters were disabled.
This enables an emulation for that configuration.
Updating the libc++ Docker image to Ubuntu Focal caused some breakage.
This was temporary disabled in D112737. This re-enables four of these
tests.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D113133
These can't be made constexpr-constructible (constinit'able),
so they aren't C++20-conforming. Also, the platform versions are
going to be bigger than the atomic/futex version, so we'd have
the awkward situation that `semaphore<42>` could be bigger than
`semaphore<43>`, and that's just silly.
Differential Revision: https://reviews.llvm.org/D110110
There's a lot of duplicated calls to find various compiler-rt libraries
from build of runtime libraries like libunwind, libc++, libc++abi and
compiler-rt. The compiler-rt helper module already implemented caching
for results avoid repeated Clang invocations.
This change moves the compiler-rt implementation into a shared location
and reuses it from other runtimes to reduce duplication and speed up
the build.
Differential Revision: https://reviews.llvm.org/D88458
There's a lot of duplicated calls to find various compiler-rt libraries
from build of runtime libraries like libunwind, libc++, libc++abi and
compiler-rt. The compiler-rt helper module already implemented caching
for results avoid repeated Clang invocations.
This change moves the compiler-rt implementation into a shared location
and reuses it from other runtimes to reduce duplication and speed up
the build.
Differential Revision: https://reviews.llvm.org/D88458
This header was transitively included to provide the definition of
__lc_ctype_ptr that we use on AIX, but that is fragile as it depends on
the settings of compatibility macros, so we explicitly include it here
to avoid that scenario.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D111239
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
Priorities below 101 are reserved for the implementation, so that's what
we should be using here. That is unfortunately only supported on more
recent versions of Clang. See https://reviews.llvm.org/D31413 for details.
Differential Revision: https://reviews.llvm.org/D95972
In basic_string and vector, we've been encapsulating all exception
throwing code paths in helper functions of a base class, which are defined
in the compiled library. For example, __vector_base_common defines two
methods, __throw_length_error() and __throw_out_of_range(), and the class
is externally instantiated in the library. This was done a long time ago,
but after investigating, I believe the goal of the current design was to:
1. Encapsulate the code to throw an exception (which is non-trivial) in
an externally-defined function so that the important code paths that
call it (e.g. vector::at) are free from that code. Basically, the
intent is for the "hot" code path to contain a single conditional jump
(based on checking the error condition) to an externally-defined function,
which handles all the exception-throwing business.
2. Avoid defining this exception-throwing function once per instantiation
of the class template. In other words, we want a single copy of
__throw_length_error even if we have vector<int>, vector<char>, etc.
3. Encapsulate the passing of the container-specific string (i.e. "vector"
and "basic_string") to the underlying exception-throwing function
so that object files don't contain those duplicated string literals.
For example, we'd like to have a single "vector" string literal for
passing to `std::__throw_length_error` in the library, instead of
having one per translation unit.
However, the way this is achieved right now has two problems:
- Using a base class and exporting it is really weird - I've been confused
about this ever since I first saw it. It's just a really unusual way of
achieving the above goals. Also, it's made even worse by the fact that
the definitions of __throw_length_error and __throw_out_of_range appear
in the headers despite always being intended to be defined in the compiled
library (via the extern template instantiation).
- We end up exporting those functions as weak symbols, which isn't great
for load times. Instead, it would be better to export those as strong
symbols from the library.
This patch fixes those issues while retaining ABI compatibility (e.g. we
still export the exact same symbols as before). Note that we need to
keep the base classes as-is to avoid breaking the ABI of someone who
might inherit from std::basic_string or std::vector.
Differential Revision: https://reviews.llvm.org/D111173
Even if these comments have a benefit in .h files (for editors that
care about language but can't be configured to treat .h as C++ code),
they certainly have no benefit for files with the .cpp extension.
Discussed in D110794.
The file was a duplicate of atomic_support.h in libc++. Since we now
require the libc++ sources in order to build libc++abi, it's OK to
remove this duplication.
Thanks to @chandlerc for noticing this.
Differential Revision: https://reviews.llvm.org/D110103
The aim is to add the missing z/OS specific implementations for mbsnrtowcs and wcsnrtombs, as part of libc++.
Differential Revision: https://reviews.llvm.org/D98207
Summary:
AIX have 2 byte wchar in 32 bit mode and 4 byte wchar in 64 bit mode.
This patch add more missing short wchar handling under the existing _LIBCPP_SHORT_WCHAR macro.
Marked test case ctor_move.pass.cpp as XFAIL for 32-bit mode on AIX because UTF-8 constants used cannot be converted to 2-byte wchar (by xingxue).
Authored by: jasonliu
Reviewed by: ldionne, zibi, SeanP, libc++
Differential Revision: https://reviews.llvm.org/D100777
There is a lot more we can do, in particular in <type_traits>, but this
removes some workarounds that were gated on checking a specific compiler
version.
Differential Revision: https://reviews.llvm.org/D108923
We will try to use GetSystemTimePreciseAsFileTime if possible.
Reference: 59195b2d7f/.
Reviewed By: compnerd, #libc, mstorsjo, ldionne
Differential Revision: https://reviews.llvm.org/D104987
Based on https://github.com/NuxiNL/cloudlibc, it appears that the CloudABI
project has been abandoned. This patch removes a bunch of CloudABI specific
logic that had been added to support that platform.
Note that some knobs like LIBCXX_ENABLE_STDIN and LIBCXX_ENABLE_STDOUT
coud be useful in their own right, however those are currently broken.
If we want to re-add such knobs in the future, we can do it like we've
done it for localization & friends so that we can officially support
that configuration.
Differential Revision: https://reviews.llvm.org/D108637
That's not necessary anymore, since we always build the dylib with
C++11 capabilities nowadays.
Differential Revision: https://reviews.llvm.org/D107772
Adds a new CMake option to disable the usage of incomplete headers.
These incomplete headers are not guaranteed to be ABI stable. This
option is intended to be used by vendors so they can avoid their users
from code that's not ready for production usage.
The option is enabled by default.
Differential Revision: https://reviews.llvm.org/D106763
Building the libraries with -fPIC ensures that we can link an executable
against the static libraries with -fPIE. Furthermore, there is apparently
basically no downside to building the libraries with position independent
code, since modern toolchains are sufficiently clever.
This commit enforces that we always build the runtime libraries with -fPIC.
This is another take on D104327, which instead makes the decision of whether
to build with -fPIC or not to the build script that drives the runtimes'
build.
Fixes http://llvm.org/PR43604.
Differential Revision: https://reviews.llvm.org/D104328
While we can debate on the value of passing by const value, there is no
arguing that it's confusing to do so in some circumstances, such as when
marking a pointer parameter as being const (did you mean a pointer-to-const?).
This commit fixes a few issues along those lines.
If building code like this:
unsigned long val = 1000;
snprintf(buf, sizeof(buf), "%+lu", val);
with clang, clang warns
warning: flag '+' results in undefined behavior with 'u' conversion specifier [-Wformat]
Therefore, don't construct such undefined format strings. (There's
no compiler warnings here, as the compiler can't inspect dynamically
assembled format strings.)
This fixes number formatting in mingw-w64 if built with
`__USE_MINGW_ANSI_STDIO` defined (there, the '+' flag causes a
leading plus to be printed when formatting unsigned numbers too,
while the '+' flag doesn't cause any extra leading plus in other
stdio implementations).
Differential Revision: https://reviews.llvm.org/D103444
If the nested create_directory call fails, we'd still want to
re-report the errors with the create_directories function name,
which is what the caller called.
This fixes one aspect from MS STL's tests for std::filesystem.
Differential Revision: https://reviews.llvm.org/D102365
Nikolas Klauser