These functions weren't added until API 26 (Android 8.0), but libc++ is
supported for API 21 and up.
These APIs are undeclared as of r.android.com/3216959.
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>`.
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
In libc++'s `wchar.h`, before we forward to the system `wchar.h`, we set `__CORRECT_ISO_CPP_WCHAR_H_PROTO` to ensure it defines the correct signature (e.g. `extern "C++" const wchar_t *wmemchr` and not `extern wchar_t *wmemchr`). After D148542, there are cases where we include the system `wchar.h` from within `__mbstate_t.h` without setting that, and so we get a function type mismatch if we transitively include `wchar.h` through multiple headers in a modules-enabled build. Consistently setting it here resolves those build errors.
Alternative 1: we could put this in `__config` instead. I chose to put it here for a more limited scope.
Alternative 2: we could patch `wchar.h` itself to work correctly and remove references `__CORRECT_ISO_CPP_WCHAR_H_PROTO` from libc++ entirely. It does already set it, but with an additional condition that it is being built by GCC >= 4.4. Clang does pretend to be GCC via `__GNUC__` etc. which can be controlled via `-fgnuc-version` command line flags, but that might have other consequences.
Reviewed By: ldionne, #libc, MaskRay
Differential Revision: https://reviews.llvm.org/D150015
These test cases were fixed with AIX 73TL1, and are currently passing on AIX machines with that fix. This fix has also been backported to the 7.2 service line. These were tested on a machine with AIX 7.2 TL 5 SP4 installed.
Differential Revision: https://reviews.llvm.org/D148040
This has been done using the following command
find libcxx/test -type f -exec perl -pi -e 's|^([^/]+?)((?<!::)size_t)|\1std::\2|' \{} \;
And manually removed some false positives in std/depr/depr.c.headers.
The `std` module doesn't export `::size_t`, this is a preparation for that module.
Reviewed By: ldionne, #libc, EricWF, philnik
Differential Revision: https://reviews.llvm.org/D146088
When support for declaring the c8rtomb() and mbrtoc8() functions within the
std namespace was added in commit 7e7013c5d4b1b3996c8dba668c5a94bb33b2999b,
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__`.
When we define the const-correct overloads of <string.h> functions in
libc++ itself, use builtins whenever possible. This avoids depending on
the presence of these functions in the C library headers.
Also, as a fly-by, improve the tests for these functions since we
basically didn't check anything but their signature. We could have
used the wrong builtin (as long as the signature matched) without ever
noticing, which was quite scary.
Differential Revision: https://reviews.llvm.org/D138684
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
Since those features are general properties of the environment, it makes
sense to use them from libc++abi too, and so the name libcpp-has-no-xxx
doesn't make sense.
Differential Revision: https://reviews.llvm.org/D126482
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
Vendors take libc++ and ship it in various ways. Some vendors might
ship it differently from what upstream LLVM does, i.e. the install
location might be different, some ABI properties might differ, etc.
In the past few years, I've come across several instances where
having a place to test some of these properties would have been
incredibly useful. I also just got bitten by the lack of tests
of that kind, so I'm adding some now.
The tests added by this commit for Apple platforms have numerous
TODOs that capture discrepancies between the upstream LLVM CMake
and the slightly-modified build we perform internally to produce
Apple's system libc++. In the future, the goal would be to upstream
all those differences so that it's possible to build a faithful
Apple system libc++ with the upstream LLVM sources only.
But this isn't only useful for Apple - this lays out the path for
any vendor being able to add their own checks (either upstream or
downstream) to libc++.
Differential Revision: https://reviews.llvm.org/D110736
Before this patch, we had features named 'libc++', 'libstdc++' and
'msvc' to describe the three implementations that use our test suite.
This patch renames them to 'stdlib=libc++', 'stdlib=libstdc++', etc
to avoid confusion between MSVC's STL and the MSVC compiler (or Clang
in MSVC mode).
Furthermore, this prepares the terrain for adding support for additional
"implementations" to the test suite. Basically, I'd like to be able to
treat Apple's libc++ differently from LLVM's libc++ for the purpose of
testing, because those effectively behave in different ways in some aspects.
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
In 5fd17ab, we worked around the Apple system headers not providing
const-correct overloads for some <string.h> functions. However, that
required an attribute that was only present in recent Clangs at the
time. We can now assume that all supported Clang versions on Apple
platforms do support that attribute.
Differential Revision: https://reviews.llvm.org/D100477
The tests expect that the <cuchar> include should fail. When libc++
is built on top of the MSVC runtime, the header does exist provided
by MSVC. Therefore, just mark the test as unsupported on windows,
to avoid tests that unexpectedly succeed.
Differential Revision: https://reviews.llvm.org/D99096
Summary:
Freestanding is *weird*. The standard allows it to differ in a bunch of odd
manners from regular C++, and the committee would like to improve that
situation. I'd like to make libc++ behave better with what freestanding should
be, so that it can be a tool we use in improving the standard. To do that we
need to try stuff out, both with "freestanding the language mode" and
"freestanding the library subset".
Let's start with the super basic: run the libc++ tests in freestanding, using
clang as the compiler, and see what works. The easiest hack to do this:
In utils/libcxx/test/config.py add:
self.cxx.compile_flags += ['-ffreestanding']
Run the tests and they all fail.
Why? Because in freestanding `main` isn't special. This "not special" property
has two effects: main doesn't get mangled, and main isn't allowed to omit its
`return` statement. The first means main gets mangled and the linker can't
create a valid executable for us to test. The second means we spew out warnings
(ew) and the compiler doesn't insert the `return` we omitted, and main just
falls of the end and does whatever undefined behavior (if you're luck, ud2
leading to non-zero return code).
Let's start my work with the basics. This patch changes all libc++ tests to
declare `main` as `int main(int, char**` so it mangles consistently (enabling us
to declare another `extern "C"` main for freestanding which calls the mangled
one), and adds `return 0;` to all places where it was missing. This touches 6124
files, and I apologize.
The former was done with The Magic Of Sed.
The later was done with a (not quite correct but decent) clang tool:
https://gist.github.com/jfbastien/793819ff360baa845483dde81170feed
This works for most tests, though I did have to adjust a few places when e.g.
the test runs with `-x c`, macros are used for main (such as for the filesystem
tests), etc.
Once this is in we can create a freestanding bot which will prevent further
regressions. After that, we can start the real work of supporting C++
freestanding fairly well in libc++.
<rdar://problem/47754795>
Reviewers: ldionne, mclow.lists, EricWF
Subscribers: christof, jkorous, dexonsmith, arphaman, miyuki, libcxx-commits
Differential Revision: https://reviews.llvm.org/D57624
llvm-svn: 353086
to reflect the new license. These used slightly different spellings that
defeated my regular expressions.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351648
This patch does the following:
* Remove <__config> includes from some container tests.
* Guards uses of std::launch::any in async tests because it's an extension.
* Move "test/std/extensions" to "test/libcxx/extensions"
* Moves various non-standard tests including those in "sequences/vector",
"std/localization" and "utilities/meta".
llvm-svn: 267981
<string.h> and wcschr, wcspbrk, wcsrchr, wmemchr, and wcsstr from <wchar.h> to
provide a const-correct overload set even when the underlying C library does
not.
This change adds a new macro, _LIBCPP_PREFERRED_OVERLOAD, which (if defined)
specifies that a given overload is a better match than an otherwise equally
good function declaration without the overload. This is implemented in modern
versions of Clang via __attribute__((enable_if)), and not elsewhere.
We use this new macro to define overloads in the global namespace for these
functions that displace the overloads provided by the C library, unless we
believe the C library is already providing the correct signatures.
llvm-svn: 260337
One of the aspects of CloudABI is that it aims to help you write code
that is thread-safe out of the box. This is very important if you want
to write libraries that are easy to reuse. For CloudABI we decided to
not provide the thread-unsafe functions. So far this is working out
pretty well, as thread-unsafety issues are detected really early on.
The following patch adds a knob to libc++,
_LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS, that can be set to disable
thread-unsafe functions that can easily be avoided in practice. The
following functions are not thread-safe:
- <clocale>: locale handles should be preferred over setlocale().
- <cstdlib>: mbrlen(), mbrtowc() and wcrtomb() should be preferred over
their non-restartable counterparts.
- <ctime>: asctime(), ctime(), gmtime() and localtime() are not
thread-safe. The first two are also deprecated by POSIX.
Differential Revision: http://reviews.llvm.org/D8703
Reviewed by: marshall
llvm-svn: 240527
The idea behind Nuxi CloudABI is that it is targeted at (but not limited to)
running networked services in a sandboxed environment. The model behind stdin,
stdout and stderr is strongly focused on interactive tools in a command shell.
CloudABI does not support the notion of stdin and stdout, as 'standard
input/output' does not apply to services. The concept of stderr does makes
sense though, as services do need some mechanism to log error messages in a
uniform way.
This patch extends libc++ in such a way that std::cin and std::cout and the
associated <cstdio>/<cwchar> functions can be disabled through the flags
_LIBCPP_HAS_NO_STDIN and _LIBCPP_HAS_NO_STDOUT, respectively. At the same time
it attempts to clean up src/iostream.cpp a bit. Instead of using a single array
of mbstate_t objects and hardcoding the array indices, it creates separate
objects that declared next to the iostream objects and their buffers. The code
is also restructured by interleaving the construction and setup of c* and wc*
objects. That way it is more obvious that this is done identically.
The c* and wc* objects already have separate unit tests. Make use of this fact
by adding XFAILs in case libcpp-has-no-std* is set. That way the tests work in
both directions. If stdin or stdout is disabled, these tests will therefore
test for the absence of c* and wc*.
Differential Revision: http://reviews.llvm.org/D8340
llvm-svn: 233275
