This patch updates algorithms in <numeric> to use std::move
based on p0616r0. Moving values instead of copying them
creates huge speed improvements (see the paper for details).
Differential Revision: https://reviews.llvm.org/D61170
There were a couple of places where we needed to call the underlying
platform's aligned allocation/deallocation function. Instead of having
the same logic all over the place, extract the logic into a pair of
helper functions __libcpp_aligned_alloc and __libcpp_aligned_free.
The code in libcxxabi/src/fallback_malloc.cpp looks like it could be
simplified after this change -- I purposefully did not simplify it
further to keep this change as straightforward as possible, since it
is touching very important parts of the library.
Also, the changes in libcxx/src/new.cpp and libcxxabi/src/stdlib_new_delete.cpp
are basically the same -- I just kept both source files in sync.
The underlying reason for this refactoring is to make it easier to support
platforms that provide aligned allocation through C11's aligned_alloc
function instead of posix_memalign. After this change, we'll only have
to add support for that in a single place.
Differential Revision: https://reviews.llvm.org/D91379
Implements P1956: On the names of low-level bit manipulation functions.
Users may use older versions of libc++ or other standard libraries with the old names. In order to keep compatibility the old functions are kept, but marked as deprecated.
The patch also adds a new config macro `_LIBCPP_DEPRECATED_MSG`. Do you prefer a this is a separate patch?
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D90551
Zoe Carver says: "We decided that libc++ only supports C++20 constexpr algorithms
when `is_constant_evaluated` is also supported. Here's a link to the discussion."
https://reviews.llvm.org/D65721#inline-735682
Remove _LIBCPP_HAS_NO_BUILTIN_IS_CONSTANT_EVALUATED from tests, too.
See Louis's 5911e6a885 if needed to fix bots.
I've applied `UNSUPPORTED: clang-8` preemptively to the altered tests;
I don't know for sure that this was needed, because no clang-8 buildbots
are triggered on pull requests.
Fixes LWG issue 2724: "The protected virtual member functions of memory_resource should be private."
Differential Revision: https://reviews.llvm.org/D66615
This reverts commit 620adacf87.
Fix: unsupport C++03 for the new test, define helpers before __swap_allocator
(1) Add _VSTD:: qualification to __swap_allocator.
(2) Add _VSTD:: qualification consistently to __to_address.
(3) Add some more missing _VSTD:: to <vector>, with a regression test.
This part is cleanup after d9a4f936d0.
Note that a vector whose allocator actually runs afoul of any of these ADL calls will
likely also run afoul of simple things like `v1 == v2` (which is also an ADL call).
But, still, libc++ should be consistent in qualifying function calls wherever possible.
Relevant blog post: https://quuxplusone.github.io/blog/2019/09/26/uglification-doesnt-stop-adl/
Differential Revision: https://reviews.llvm.org/D91708
Not all platforms support priority attribute. I'm moving conditional definition of this attribute to `include/__config`.
Reviewed By: #libc, aaron.ballman
Differential Revision: https://reviews.llvm.org/D91565
(1) Add _VSTD:: qualification to __swap_allocator.
(2) Add _VSTD:: qualification consistently to __to_address.
(3) Add some more missing _VSTD:: to <vector>, with a regression test.
This part is cleanup after d9a4f936d0.
Note that a vector whose allocator actually runs afoul of any of these ADL calls will
likely also run afoul of simple things like `v1 == v2` (which is also an ADL call).
But, still, libc++ should be consistent in qualifying function calls wherever possible.
Relevant blog post: https://quuxplusone.github.io/blog/2019/09/26/uglification-doesnt-stop-adl/
Differential Revision: https://reviews.llvm.org/D91708
This commit makes it clear that the typeinfo comparison implementation
is automatically selected by default, and that the CMake option only
overrides the value. This has been a source of confusion and bugs ever
since we've introduced complexity in that area, so I'm trying to simplify
it while still allowing for some control on the implementation.
Differential Revision: https://reviews.llvm.org/D91574
These functions are called directly from the public installed
headers, and thus need to be exported in DLL builds, just like
some other functions in the same header (e.g. snprintf_l).
This fixes e.g. test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_float.pass.cpp
in mingw configurations.
Differential Revision: https://reviews.llvm.org/D91328
These changes cause substantial binary size increases for non-opt builds.
For example, the visit.pass.cpp test grows from 20k to 420k.
Further work will be done to re-land this patch without the size increases,
but that work is proving too tricky to fix forward.
This patch fully reverts:
* 35d2269111
And it partially reverts:
* bb43a0cd4a
The latter of which added XFAIL's to new variant tests
because the new implementation needlessly makes non-throwing code
paths in variant invoke throwing code.
This means the reverted change also breaks source backwards compat
with code compiled on OS X targeting older system dylibs. There is no
need for this to be the case. We should fix it before recommitting.
Reviewed as:
https://reviews.llvm.org/D91662
Erroring out prevents the library from working with other file formats
(e.g. in embedded). Since that error does not guard us from doing something
incorrect, it seems fine to just remove it.
This patch adds a shim for missing time functions on z/OS, and adds a
layer of indirection to account for differences in the timespec struct
on different systems.
This was originally committed as 173b51169b and reverted in 777ca48c9f
because the original commit also checked-in unrelated changes.
Differential Revision: https://reviews.llvm.org/D87940
The unavailability of posix_memalign on z/OS forces us to define _LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION'. The use of posix_memalign is being used in libcxx/src/new.cpp.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D90178
This commit adds new explicit instantiations for some classes in <iostream>
in the library. This is done after noticing that many programs that use
streams end up containing weak definitions of these classes, which has a
negative impact on both code size and load times (due to the need to
resolve weak symbols at load time). Note that we are just adding the
additional explicit instantiations for the `char` specializations, since
the `wchar_t` specializations are not used as often, and as a result there
wouldn't be a clear benefit.
This change is not an ABI break, since we are just adding additional
symbols.
Differential Revision: https://reviews.llvm.org/D90677
This patch is one part of many steps required to build libc++ and libc++abi libraries on z/OS. This particular deals with time related functions and consists of the following 3 parts.
1) Initialization of :timeval within libc++ library need to be adjusted to work on z/OS.
The following is z/OS definition from time.h which includes additional aggregate member.
typedef signed int suseconds_t;
struct timeval {
time_t tv_sec;
char tv_usec_pad[4];
suseconds_t tv_usec;
};
In contracts the following is definition from time.h on Linux.
typedef long int __suseconds_t;
struct timeval
{
__time_t tv_sec;
__suseconds_t tv_usec;
};
2) In addition, retrieving ::timespec within libc++ library needs to be adjusted to compensate the difference of some of the members of ::stat depending of the target host.
Here are the 2 members in conflict on z/OS extracted from stat.h.
struct stat {
...
time_t st_atime;
time_t st_mtime;
...
};
In contract here is Linux equivalent from stat.h.
struct stat
{
...
struct timespec st_atim;
struct timespec st_mtim;
...
};
3) On Linux both members are of type timespec whereas on z/OS an object of type timespec need to be constructed first before retrieving it within libc++ library.
The libc++ header file __threading_support calls nanosleep, which is not available on z/OS.
The equivalent functionality will be implemented by using both sleep() and usleep().
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D87940
This is consistent with what's done in locale.cpp, and it ensures that
we get the default rune table whenever _LIBCPP_PROVIDES_DEFAULT_RUNE_TABLE
is defined, regardless of the actual platform.
Differential Revision: https://reviews.llvm.org/D91074
This patch changes how linear_congruential_engine picks its randomization
algorithm. It adds two restrictions, `_OverflowOK` and `_SchrageOK`.
`_OverflowOK` means that m is a power of two so using the classic
`(a * x + c) % m` will create a meaningless overflow. The second checks
that Schrage's algorithm will produce results that are in bounds of min
and max. This patch fixes https://llvm.org/PR27839.
Differential Revision: D65041
The aim of this patch is to enable POSIX _l functions for z/OS. In particular, the functions are provided with libc++ and this patch resorts to the fallback functions. Nonetheless, the functions are being added so the implementation of the ctype<> member functions can call them. The following changes were needed to allow for a successful build when using the libc++ library for z/OS.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D90319
The current way we test this is pretty cheap, i.e. we download previously
released macOS dylibs and run against that. Ideally, we would require a
full host running the appropriate version of macOS, and we'd execute the
tests using SSH on that host. But since we don't have such hosts available
easily for now, this is better than nothing.
At the same time, also fix some tests that were failing when back
deploying.
Differential Revision: https://reviews.llvm.org/D90869
Currently, vendor-specific availability markup is enabled by default.
This means that even when building against trunk libc++, the headers
will by default prevent you from using some features that were not
released in the dylib on your target platform. This is a source of
frustration since people building libc++ from sources are usually not
trying to use some vendor's released dylib.
For that reason, I've been thinking for a long time that availability
annotations should be off by default, which is the primary change that
this commit enables.
In addition, it reworks the implementation to make it easier for new
vendors to add availability annotations for their platform, and it
refreshes the documentation to reflect the current state of the codebase.
Finally, a CMake configuration option is added to control whether
availability annotations should be turned on for the flavor of libc++
being created. The intent is for vendors like Apple to turn it on, and
for the upstream libc++ to leave it off (the default).
Differential Revision: https://reviews.llvm.org/D90843
Those are part of the library, and shipping them just adds a tiny bit of
size to the distribution. This was originally added in b422ecc7de to
make it possible to match the Makefile build, which doesn't exist anymore.
The upside is build system simplification.
Before 6db314e86b, when running cmake with clang, libcxx, and
compiler-rt enabled, building `ninja all` would run the
generate-cxx-headers target, due to the sanitizers depending on it.
After 6db314e86b, if LIBCXX_ENABLE_SHARED and LIBCXX_ENABLE_STATIC
and LIBCXX_INCLUDE_TESTS and LIBCXX_ENABLE_EXPERIMENTAL_LIBRARY are
disabled (https://reviews.llvm.org/D82702#2153627), `ninja all`
no longer copies the libcxx headers, which means clang can't compile
programs like `#include <string>` on macOS.
Explicitly add the copy target to the all target to restore the old
behavior.
On windows, wchar_t is 16 bit, while we might be widening chars to
char32_t.
This cast had been present since the initial commit, and removing it
doesn't seem to make any tests fail.
Differential Revision: https://reviews.llvm.org/D90228
When porting libc++ to embedded systems, it can be useful to drop support
for localization, which these systems don't implement or care about.
Differential Revision: https://reviews.llvm.org/D90072
This is a massive revert of the following commits (from most revent to oldest):
2b9b7b5775.
529ac3319728270234f169c2087283b5aa67446e5d796645d6
After checking-in the __config_site change, a lot of things started breaking
due to widespread reliance on various aspects of libc++'s build, notably the
fact that we can include the headers from the source tree, but also reliance
on various "internal" CMake variables used by the runtimes build and compiler-rt.
These were unintended consequences of the change, and after two days, we
still haven't restored all the bots to being green. Instead, now that I
understand what specific areas this will blow up in, I should be able to
chop up the patch into smaller ones that are easier to digest.
See https://reviews.llvm.org/D89041 for more details on this adventure.
On old Apple platforms (pre 10.9), we couldn't rely on the iostreams
explicit instantiations being part of the dylib. However, we don't
support back-deploying to such old deployment targets anymore, so the
workaround can be dropped.
This commit should really be named "Workaround external projects depending
on libc++ build system implementation details". It seems that the compiler-rt
build (and perhaps other projects) is relying on the fact that we copy libc++
and libc++abi headers to `<build-root>/include/c++/v1`. This was changed
by 5d796645, which moved the headers to `<build-root>/projects/libcxx/include/c++/v1`
and broke the compiler-rt build.
I'm committing this workaround to fix the compiler-rt build, but we should
remove reliance on implementation details like that. The correct way to
setup the compiler-rt build would be to "link" against the `cxx-headers`
target in CMake, or to run `install-cxx-headers` using an appropriate
installation prefix, and then manually add a `-I` path to that location.
Prior to this patch, we would generate a fancy <__config> header by
concatenating <__config_site> and <__config>. This complexifies the
build system and also increases the difference between what's tested
and what's actually installed.
This patch removes that complexity and instead simply installs <__config_site>
alongside the libc++ headers. <__config_site> is then included by <__config>,
which is much simpler. Doing this also opens the door to having different
<__config_site> headers depending on the target, which was impossible before.
It does change the workflow for testing header-only changes to libc++.
Previously, we would run `lit` against the headers in libcxx/include.
After this patch, we run it against a fake installation root of the
headers (containing a proper <__config_site> header). This makes use
closer to testing what we actually install, which is good, however it
does mean that we have to update that root before testing header changes.
Thus, we now need to run `ninja check-cxx-deps` before running `lit` by
hand.
This commit was originally applied in 1e46d1aa3 and reverted in eb60c487
because it broke the libc++abi and libunwind test suites. This has now
been fixed.
Differential Revision: https://reviews.llvm.org/D89041
Prior to this patch, we would generate a fancy <__config> header by
concatenating <__config_site> and <__config>. This complexifies the
build system and also increases the difference between what's tested
and what's actually installed.
This patch removes that complexity and instead simply installs <__config_site>
alongside the libc++ headers. <__config_site> is then included by <__config>,
which is much simpler. Doing this also opens the door to having different
<__config_site> headers depending on the target, which was impossible before.
It does change the workflow for testing header-only changes to libc++.
Previously, we would run `lit` against the headers in libcxx/include.
After this patch, we run it against a fake installation root of the
headers (containing a proper <__config_site> header). This makes use
closer to testing what we actually install, which is good, however it
does mean that we have to update that root before testing header changes.
Thus, we now need to run `ninja check-cxx-deps` before running `lit` by
hand.
Differential Revision: https://reviews.llvm.org/D89041
This patch ensures that __shared_weak_count provides a consistent vtable
regardless of if RTTI is enabled or if we are targeting a static or shared
libc++ build.
This patch is technically ABI breaking, but only for a very specific
configuration that no vendor should be shipping.
Note that _LIBCPP_BUILD_STATIC is not normally defined when building
libc++.a, but instead it must be manually provided by the user or the
__config_site.
Differential Revision: https://reviews.llvm.org/D32838
We included <istream> and <ostream> from <random>, but really it is
sufficient to include <iosfwd> if we make sure we access ios_base
members through a dependent type. This allows us to break a hard
dependency of <random> on locales.
Some platforms, like several embedded platforms, do not provide a source
of randomness through a random device. This commit makes it possible to
build and test libc++ for such platforms, i.e. without std::random_device.
Surprisingly, the only functionality that doesn't work on such platforms
is std::random_device itself -- everything else in <random> still works,
one just has to find alternative ways to seed the PRNGs.
Due to the need to support compilers that implement builtin operator
new/delete but not their align_val_t overloaded versions, there was a
lot of complexity. By assuming that a compiler that supports the builtin
new/delete operators also supports their align_val_t overloads, the code
can be simplified quite a bit.
Differential Revision: https://reviews.llvm.org/D88301
We don't support any compiler that doesn't support variadics and rvalue
references in C++03 mode, so these workarounds can be dropped. There's
still *a lot* of cruft related to these workarounds, but I try to tackle
a bit of it here and there.
__clear_and_shrink() was added in D41976, and a test was added alongside
it to make sure that the string invariants were maintained. However, it
appears that the test never ran under UBSan before, which would have
highlighted the fact that it doesn't actually maintain the string
invariants.
Differential Revision: https://reviews.llvm.org/D88849
Some system headers define __constructor and __destructor macros (for
Clang attributes constructor and destructor). While this is badly
behaved, it is easy for libc++ to work around this issue.
The debug mode always had three possibilities:
- _LIBCPP_DEBUG is undefined => no assertions
- _LIBCPP_DEBUG == 0 => some assertions
- _LIBCPP_DEBUG == 1 => some assertions + iterator checks
This was documented that way, however the code did not make this clear
at all. The discrepancy between _LIBCPP_DEBUG and _LIBCPP_DEBUG_LEVEL
was especially confusing. I reworked how the various macros are defined
without changing anything else to make the code clearer.
This seems to have been added a long time ago as a temporary help
for debugging some <regex> issue, but it's really the same as
_LIBCPP_EXTERN_TEMPLATE.
This is a partial revert of D62155. Rather than copying libc++ headers
into the build directory to be later overwritten by the final headers,
use -isystem flag to access libc++ headers during CMake checks. This
should address the occasional flake we've seen, especially on Windows
builders where CMake fails to overwrite __config with the final version.
Differential Revision: https://reviews.llvm.org/D88454
* Use an empty struct instead of a member pointer to represent this
type, so that we don't actually pass a zero member pointer at runtime.
* Mark the constructor as consteval to ensure that no code is emitted
for it whenever possible.
* Add a honeypot constructor to reject all non-int arguments, so that
the only argument that can arrive at the real constructor is the
literal 0.
This results in better generated code, and rejecting invalid comparisons
against nullptr, 0L, and so on, while also rejecting invalid comparisons
against (1-1) and similar that would be allowed if we required an
integer constant expression with value 0.
Differential Revision: https://reviews.llvm.org/D85051
We're technically not allowed by the Standard to call ::operator new in
constexpr functions like __libcpp_allocate. Clang doesn't seem to complain
about it, but GCC does.
fdc41e11f was reverted in e46c1def5 because it broke the C++11 build.
We shouldn't be using enable_if_t in C++11, instead we must use
enable_if<...>::type.
This reverts commit fdc41e11f9. It causes the
libcxx/modules/stds_include.sh.cpp test to fail with:
libcxx/include/ostream:1039:45: error: no template named 'enable_if_t'; did you mean 'enable_if'?
template <class _Stream, class _Tp, class = enable_if_t<
Still investigating what's causing this and reverting in the meantime to get
the bots green again.
Libc++ had an issue where nonsensical code like
decltype(std::stringstream{} << std::vector<int>{});
would compile, as long as you kept the expression inside decltype in
an unevaluated operand. This turned out to be that we didn't implement
LWG1203, which clarifies what we should do in that case.
rdar://58769296
This commit adds std::construct_at, and marks various members of
std::allocator_traits and std::allocator as constexpr. It also adds
tests and turns the existing tests into hybrid constexpr/runtime tests.
Thanks to Richard Smith for initial work on this, and to Michael Park
for D69803, D69132 and D69134, which are superseded by this patch.
Differential Revision: https://reviews.llvm.org/D68364
Mitsuru Kariya reported the map operations insert_or_assign with a hint
violates the complexity requirement. The function no longer uses a lower_bound,
which caused the wrong complexity.
Fixes PR38722: [C++17] std::map::insert_or_assign w/ hint violate complexity requirements
Differential Revision: https://reviews.llvm.org/D62779
We don't support GCC in C++03 mode, and Clang provides variadic templates
even in C++03 mode. So there's effectively no supported compiler that
doesn't support variadic templates.
This effectively gets rid of all uses of _LIBCPP_HAS_NO_VARIADICS, but
some workarounds for the lack of variadics remain.
Otherwise, we're declaring a non-static member function, and that
gives errors in C++11 because of the change of semantics between
C++11 and C++14 for non-const constexpr member functions.
This was always intended to be a friend declaration.
https://llvm.org/PR45099 notes (correctly) that we're inconsistent in memory
allocation in `std::any`. We allocate memory with `std::allocator<T>::allocate`,
construct with placement new, destroy by calling the destructor directly, and
deallocate by calling `delete`. Most of those are customizable by the user,
but in different ways.
The standard is silent on how these things are to be accomplished.
This patch makes it so we use `allocator_traits<allocator<T>>` for all
of these operations (allocate, construct, destruct, deallocate).
This is, at least, consistent.
Fixes https://llvm.org/PR45099.
Differential Revision: https://reviews.llvm.org/D81133
This patch makes `std::rotate` a constexpr. In doing so, this patch also
updates the internal `__move` and `__move_backward` funtions to be
constexpr.
This patch was previously reverted in ed653184ac because it was missing
some UNSUPPORTED markup for older compilers. This commit adds it.
Differential Revision: https://reviews.llvm.org/D65721
cppreference lists the support for this paper as partial.
I found 4 functions which the paper marks as `constexpr`,
but did not use the appropriate macro.
Differential Revision: https://reviews.llvm.org/D84275
This patch makes `std::rotate` a constexpr. In doing so, this patch also
updates the internal `__move` and `__move_backward` funtions to be
constexpr.
Reviewed By: ldionne
Differential Revision: https://reviews.llvm.org/D65721
In C++20, since P0896R4, std::ostream_iterator and std::ostreambuf_iterator
must have std::ptrdiff_t instead of void as a difference_type.
Tests by Casey Carter (thanks!).
Differential Revision: https://reviews.llvm.org/D87459
D56913 introduced the _LIBCPP_FREESTANDING macro and guarded its
definition by:
#ifndef __STDC_HOSTED__
# define _LIBCPP_FREESTANDING
#endif
However, __STDC_HOSTED__ is defined as 0 in freestanding implementations
instead of undefined, which means that _LIBCPP_FREESTANDING would never
get defined. This patch corrects the above as:
#if __STDC_HOSTED__ == 0
# define _LIBCPP_FREESTANDING
#endif
Differential Revision: https://reviews.llvm.org/D86055
This commit re-applies 99f3b231cb, which was reverted in 8142425727
because it broke the modules build. The modules failure was a circular
dependency between the Darwin module and __config. Specifically, the
issue was that if <__config> includes a system header, the std_config
module depends on the Darwin module. However, the Darwin module already
depends on the std_config header because some of its headers include
libc++ headers like <ctype.h> (they mean to include the C <ctype.h>,
but libc++ headers are first in the header search path).
This is fixed by moving the workaround to <ctime> only.
https://llvm.org/PR47208
rdar://68157284
This reverts commit 99f3b231cb. It breaks
libcxx/modules/stds_include.sh.cpp on macOS as the new include to sys/cdefs.h
causes a dependency from __config to the Darwin module (which already has
a dependency on __config). This cyclic dependency breaks compiling the std
module which breaks compiling pretty much every program with ToT libc++ and
enabled modules.
I'll revert for now to get the bots green again. Sorry for the inconvenience.
There are currently some failures caused by this change internally. I'm working
to debug them and hopefully these series of patches should be recommitted by
the end of the week.
Thank you to Micheal Park for the contributions, and for allowing the temporary
rollback.
The commits reverted by this change are:
7d15ece79ce0ec7a020602197f7e50a175a96517
timespec_get is not available in Apple SDKs when (__DARWIN_C_LEVEL >= __DARWIN_C_FULL)
isn't true, which leads to libc++ trying to import ::timespec_get into
namespace std when it's not available. This issue has been reported to
Apple's libc, but we need a workaround in the meantime.
https://llvm.org/PR47208
rdar://68157284
zoecarver