`vector<bool>::const_reference` and `vector<bool>::const_iterator::reference` should be the same type.
Reviewed By: Mordante, #libc
Spies: libcxx-commits
Differential Revision: https://reviews.llvm.org/D123851
This patch implements P0674R1, i.e. support for arrays in std::make_shared
and std::allocate_shared.
Co-authored-by: Zoe Carver <z.zoelec2@gmail.com>
Differential Revision: https://reviews.llvm.org/D62641
This patch adds a lightweight assertion handler mechanism that can be
overriden at link-time in a fashion similar to `operator new`.
This is a third take on https://llvm.org/D121123 (which allowed customizing
the assertion handler at compile-time), and https://llvm.org/D119969
(which allowed customizing the assertion handler at runtime only).
This approach is, I think, the best of all three explored approaches.
Indeed, replacing the assertion handler in user code is ergonomic,
yet we retain the ability to provide a custom assertion handler when
deploying to older platforms that don't have a default handler in
the dylib.
As-is, this patch provides a pretty good amount of backwards compatibility
with the previous debug mode:
- Code that used to set _LIBCPP_DEBUG=0 in order to get basic assertions
in their code will still get basic assertions out of the box, but
those assertions will be using the new assertion handler support.
- Code that was previously compiled with references to __libcpp_debug_function
and friends will work out-of-the-box, no changes required. This is
because we provide the same symbols in the dylib as we used to.
- Code that used to set a custom __libcpp_debug_function will stop
compiling, because we don't provide that declaration anymore. Users
will have to migrate to the new way of setting a custom assertion
handler, which is extremely easy. I suspect that pool of users is
very limited, so breaking them at compile-time is probably acceptable.
The main downside of this approach is that code being compiled with
assertions enabled but deploying to an older platform where the assertion
handler didn't exist yet will fail to compile. However users can easily
fix the problem by providing a custom assertion handler and defining
the _LIBCPP_AVAILABILITY_CUSTOM_ASSERTION_HANDLER_PROVIDED macro to
let the library know about the custom handler. In a way, this is
actually a feature because it avoids a load-time error that one would
otherwise get when trying to run the code on the older target.
Differential Revision: https://reviews.llvm.org/D121478
We've been meaning to remove support for the legacy testing configuration
for a long time. This patch switches the default from the legacy config
to the appropriate new-style configuration based on a few hints.
We've been running with the new-style configuration for more than a year
in our CI, however it's possible that this will uncover issues with some
users that run the tests on platforms that we don't support yet with the
new-style configs. Unfortunately, there is no way to know about it other
than to land this patch and see whether anything breaks.
Differential Revision: https://reviews.llvm.org/D121632
It's the role of the C++ ABI library to install its own headers, not libc++.
This fixes an existing issue causing spurious CI failures where both libc++
and libc++abi would try to install <cxxabi.h> & friends in the same location,
leading to failures during the installation step.
Differential Revision: https://reviews.llvm.org/D121706
This reverts commit 276ca873. That commit has quite a history at this
point. It was first landed in dbc647643577, which broke std::shared_ptr<T const>
and was reverted in 9138666f5. It was then re-applied in 276ca873, with
the std::shared_ptr issue fixed, but it caused widespread breakage at
Google (which suggests it would cause similar breakage in the wild too),
so now I'm reverting again.
Instead, I will add a escape hatch that vendors can turn on to enable
the extension and perform a phased transition over one or two releases
like we sometimes do when things become non-trivial.
This extension is a portability trap for users, since no other standard
library supports it. Furthermore, the Standard explicitly allows
implementations to reject std::allocator<cv T>, so allowing it is
really going against the current.
This was discovered in D120684: this extension required `const_cast`ing
in `__construct_range_forward`, a fishy bit of code that can be removed
if we don't support the extension anymore.
This is a re-application of dbc647643577, which was reverted in 9138666f5
because it broke std::shared_ptr<T const>. Tests have now been added and
we've made sure that std::shared_ptr<T const> wouldn't be broken in this
version.
Differential Revision: https://reviews.llvm.org/D120996
If LIBCXX_ENABLE_SHARED isn't explicitly set on the cmake command
line, isn't set in the cache, and the libcxxabi project is configured
before libcxx, then LIBCXX_ENABLE_SHARED isn't defined yet. Once
the libcxx cmake project has been parsed, LIBCXX_ENABLE_SHARED would
have been set to its default value of ON.
This makes sure that the symbols are properly dllexported in such
a configuration scenario.
Differential Revision: https://reviews.llvm.org/D120982
This extension is a portability trap for users, since no other standard
library supports it. Furthermore, the Standard explicitly allows
implementations to reject std::allocator<cv T>, so allowing it is
really going against the current.
This was discovered in D120684: this extension required `const_cast`ing
in `__construct_range_forward`, a fishy bit of code that can be removed
if we don't support the extension anymore.
Differential Revision: https://reviews.llvm.org/D120996
Move `__quoted_output_proxy` into the one file that uses it.
A `const char*` has no associated traits class, so `std::quoted("literal")`
should be printable into any basic_ostream regardless of traits.
Use hidden-friend `operator<<` and `operator>>`, since we're permitted to.
(The exact signature is unspecified because the class itself is unspecified.)
We shouldn't support `std::quoted("literal")` in C++03 or C++11 mode.
(We do need `std::__quoted(s)` and `std::__quoted(cs)` in C++11 mode,
because they're used by `std::__fs::filesystem::path`.)
Differential Revision: https://reviews.llvm.org/D120135
Instead, folks can use the equivalent variables provided by CMake
to set those. This removal aims to reduce complexity and potential
for confusion when setting the target triple for building the runtimes,
and make it correct when `CMAKE_OSX_ARCHITECTURES` is used (right now
both `-arch` and `--target=` will end up being passed, which is downright
incorrect).
Differential Revision: https://reviews.llvm.org/D112155
`uniform_int_distribution<T>` is UB unless `T` is one of the non-character,
non-boolean integer types (`short` or larger). However, libc++ has never
enforced this. D114129 accidentally made `uniform_int_distribution<bool>`
into an error. Make it now *intentionally* an error; and likewise for the
character types and all user-defined class and enum types; but permit
`__[u]int128_t` to continue working.
Apply the same static_assert to all the integer distributions.
Differential Revision: https://reviews.llvm.org/D114920
`<filesystem>` header has been around for a while now, so we can safely remove
`<experimental/filesystem>` header. `_LIBCPP_DEPRECATED_EXPERIMENTAL_FILESYSTEM`
suggests we were going to remove `<experimental/filesystem>` in llvm 11 release,
but we never did. So, remove the experimental header now, its associated tests,
and the `_LIBCPP_DEPRECATED_EXPERIMENTAL_FILESYSTEM` macro.
Differential Revision: https://reviews.llvm.org/D119603
Standalone build have been deprecated for some time now, so this
commit removes support for those builds entirely from libc++, libc++abi
and libunwind.
This, along with the removal of other legacy ways to build, will allow
for major build system simplifications.
Differential Revision: https://reviews.llvm.org/D119255
Previously, _LIBCPP_ABI_UNSTABLE would be used interchangeably with
_LIBCPP_ABI_VERSION >= 2. This was confusing and creating unnecessary
complexity.
This patch removes _LIBCPP_ABI_UNSTABLE -- instead, the LIBCXX_ABI_UNSTABLE
CMake option will result in the LIBCXX_ABI_VERSION being set to '2', the
current unstable ABI. As a result, in the code, we only have _LIBCPP_ABI_VERSION
to check in order to query the current ABI version.
As a fly-by, this also defines the ABI namespace during CMake configuration
to reduce complexity in __config. I believe it was previously done this
way because we used to try to use __config_site as seldom as possible.
Now that we always ship a __config_site, it doesn't really matter and
I think being explicit about how the library is configured in the __config_site
is actually a feature.
Differential Revision: https://reviews.llvm.org/D119173
Back in https://reviews.llvm.org/D109459, we stopped using the C++03
emulation for std::nullptr_t by default, which was an ABI break. We
still left a knob for users to turn it back on if they were broken by
the change, with a note that we would remove that knob after one release.
The time has now come to remove the knob and clean up the std::nullptr_t
emulation.
Differential Revision: https://reviews.llvm.org/D114786
There is no practical difference between `_VSTD` and `std` so we should just remove `_VSTD`. This is the first step.
Reviewed By: ldionne, #libc
Spies: jeroen.dobbelaere, wmaxey, EricWF, lebedev.ri, __simt__, dim, mgrang, sstefan1, wenlei, smeenai, libcxx-commits, #libc_vendors
Differential Revision: https://reviews.llvm.org/D117811
I had a look at the changes since the last release and updated the
release notes with interesting changes.
It seems this time the release notes were already rather up to date :-)
If there are more interesting changes, please let me know and I'll
update the patch. I'd like to commit these changes latest next weekend
so they land before branching the 14.0 release.
I've added most active libc++ contributors. If I forgot anybody please add them.
Reviewed By: Quuxplusone, ldionne, philnik, #libc
Differential Revision: https://reviews.llvm.org/D117948
Since basic_string::reserve(n) is instantiated in the shared library but also
available to the compiler for inlining, its definition should not depend on
things like the Standard mode in use. Indeed, that flag may not match between
how the shared library is compiled and how users are compiling their own code,
resulting in ODR violations.
However, note that we retain the behavior of basic_string::reserve() to
shrink the string for backwards compatibility reasons. While it would
technically be conforming to not shrink, we believe user expectation is
for it to shrink, and so existing code might have been written based on
that assumption. We prefer to not break such code, even though that makes
basic_string::reserve() and basic_string::reserve(0) not equivalent anymore.
Fixes llvm-project#53170
Differential Revision: https://reviews.llvm.org/D117332
This adjust the version macro and sets it as completed. All parts of the paper
have been implemented, except for the parts replaced by later papers and
LWG-issues.
Adjusted the synopsis to match the synopsis in the Standard. Not yet
implemented parts of P2216 and P2418 still use the P0645 wording.
Completes:
- P0645 Text Formatting
Depends on D115991
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D115999
It was not in P0355R7, nor has it ever been so in a working draft.
Drive-by:
* tests should test something: fix loop bounds so initial value is not >= final value
* calender type streaming tests are useless - let's remove them
* don't declare printf, especially if you don't intend to use it
Differential Revision: https://reviews.llvm.org/D117638
This essentially reverts e02ed1c255d71 and puts in a new fix, which makes `path::iterator`
a true C++20 `bidirectional_iterator`, but downgrades it to an `input_iterator` in C++17.
Fixes#37852.
Differential Revision: https://reviews.llvm.org/D116489
On Apple platforms, arc4random is faster than /dev/urandom, and it is
the recommended user-space RNG according to Apple's own OS folks.
This commit adds an ABI switch to guard ABI-break-protections in
std::random_device, and starts using arc4random instead of /dev/urandom
to implement std::random_device on Apple platforms.
Note that previously, `std::random_device` would allow passing a custom
token to its constructor, and that token would be interpreted as the name
of a file to read entropy from. This was implementation-defined and
undocumented. After this change, Apple platforms will be using arc4random()
instead, and any custom token passed to the constructor will be ignored.
This behavioral change will also impact other platforms that use the
arc4random() implementation, such as OpenBSD. This should be fine since
that is effectively a relaxation of the constructor's requirements.
rdar://86638350
Differential Revision: https://reviews.llvm.org/D116045
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 30f305efe279,
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
This patch removes the ability to build the runtimes in the 32 bit
multilib configuration, i.e. using -m32. Instead of doing this, one
should cross-compile the runtimes for the appropriate target triple,
like we do for all other triples.
As it stands, -m32 has several issues, which all seem to be related to
the fact that it's not well supported by the operating systems that
libc++ support. The simplest path towards fixing this is to remove
support for the configuration, which is also the best course of action
if there is little interest for keeping that configuration. If there
is a desire to keep this configuration around, we'll need to do some
work to figure out the underlying issues and fix them.
Differential Revision: https://reviews.llvm.org/D114473
We only support Clangs that implement nullptr as an extension in C++03 mode,
and we don't support GCC in C++03 mode. Hence, this patch disables the
use of the std::nullptr_t emulation in C++03 mode by default. Doing that
is technically an ABI break since it changes the mangling for std::nullptr_t.
However:
(1) The only affected users are those compiling in C++03 mode that have
std::nullptr_t as part of their ABI, which should be reasonably rare.
(2) Those users already have a lingering problem in that their code will
be incompatible in C++03 and C++11 modes because of that very ABI break.
Hence, the only users that could really be inconvenienced about this
change is those that planned on compiling in C++03 mode forever - for
other users, we're just breaking them now instead of letting them break
themselves later on when they try to upgrade to C++11.
(3) The ABI break will cause a linker error since the mangling changed,
and will not result in an obscure runtime error.
Furthermore, if anyone is broken by this, they can define the
_LIBCPP_ABI_USE_CXX03_NULLPTR_EMULATION macro to return to the
previous behavior. We will then remove that macro after shipping
this for one release if we haven't seen widespread issues.
Concretely, the motivation for making this change is to make our own ABI
consistent in C++03 and C++11 modes and to remove complexity around the
definition of nullptr.
Furthermore, we could investigate making nullptr a keyword in C++03 mode
as a Clang extension -- I don't think that would break anyone, since
libc++ already defines nullptr as a macro to something else. Only users
that do not use libc++ and compile in C++03 mode could potentially be
broken by that.
Differential Revision: https://reviews.llvm.org/D109459
This effort is dedicated to deflake the tests of the users which depend
on the unspecified behavior of algorithms and containers. This also
might help updating the sorting algorithm in libcxx which has the
quadratic worst case in the future or at least create a new one under
flag.
For detailed design, please see the design doc I provide in the patch.
Differential Revision: https://reviews.llvm.org/D96946
