Summary:
LWG2510 makes tag types like allocator_arg_t explicitly default
constructible instead of implicitly default constructible. It also
makes the constructors for std::pair and std::tuple conditionally
explicit based on the explicit-ness of the default constructibility
for the pair/tuple's elements.
This was previously committed as r372777 and reverted in r372832 due to
the commit breaking LLVM's build in C++14 mode. This issue has now been
addressed.
Reviewers: mclow.lists
Subscribers: christof, jkorous, dexonsmith, libcxx-commits
Tags: #libc
Differential Revision: https://reviews.llvm.org/D65161
llvm-svn: 372983
Users should only get the assert() macros if they explicitly include
them.
Found after switching from the GNU C++ stdlib to the LLVM C++ stdlib.
llvm-svn: 372963
We don't support GCC 4 and older according to the documentation, so
we should pretend it doesn't exist.
This is a re-application of r372787.
llvm-svn: 372916
This declaration was previously missing despite appearing in the
synopsis. Users are still required to include <ostream> to get the
definition of the streaming operator.
llvm-svn: 372909
This also reverts:
- r372778: [libc++] Implement LWG 3158
- r372782: [libc++] Try fixing tests that fail on GCC 5 and older
- r372787: Purge mentions of GCC 4 from the test suite
Reason: the change breaks compilation of LLVM with libc++, for details see
http://lists.llvm.org/pipermail/libcxx-dev/2019-September/000599.html
llvm-svn: 372832
Summary: As suggested by @ldionne in D66178, this patch removes C++03 variadics //only//. Following patches will apply more updates.
Reviewers: ldionne, EricWF, mclow.lists
Subscribers: christof, dexonsmith, libcxx-commits, ldionne
Tags: #libc
Differential Revision: https://reviews.llvm.org/D67675
llvm-svn: 372780
Summary:
LWG 3158 marks the allocator_arg_t constructor of std::tuple as
conditionnally explicit based on whether the default constructors
of the tuple's members are explicitly default constructible.
Reviewers: EricWF, mclow.lists
Subscribers: christof, jkorous, dexonsmith, libcxx-commits
Tags: #libc
Differential Revision: https://reviews.llvm.org/D65232
llvm-svn: 372778
Summary:
LWG2510 makes tag types like allocator_arg_t explicitly default
constructible instead of implicitly default constructible. It also
makes the constructors for std::pair and std::tuple conditionally
explicit based on the explicit-ness of the default constructibility
for the pair/tuple's elements.
Reviewers: mclow.lists, EricWF
Subscribers: christof, jkorous, dexonsmith, libcxx-commits
Tags: #libc
Differential Revision: https://reviews.llvm.org/D65161
llvm-svn: 372777
std::condition_variable is currently implemented via
pthread_cond_timedwait() on systems that use pthread. This is
problematic, since that function waits by default on CLOCK_REALTIME
and libc++ does not provide any mechanism to change from this
default.
Due to this, regardless of if condition_variable::wait_until() is
called with a chrono::system_clock or chrono::steady_clock parameter,
condition_variable::wait_until() will wait using CLOCK_REALTIME. This
is not accurate to the C++ standard as calling
condition_variable::wait_until() with a chrono::steady_clock parameter
should use CLOCK_MONOTONIC.
This is particularly problematic because CLOCK_REALTIME is a bad
choice as it is subject to discontinuous time adjustments, that may
cause condition_variable::wait_until() to immediately timeout or wait
indefinitely.
This change fixes this issue with a new POSIX function,
pthread_cond_clockwait() proposed on
http://austingroupbugs.net/view.php?id=1216. The new function is
similar to pthread_cond_timedwait() with the addition of a clock
parameter that allows it to wait using either CLOCK_REALTIME or
CLOCK_MONOTONIC, thus allowing condition_variable::wait_until() to
wait using CLOCK_REALTIME for chrono::system_clock and CLOCK_MONOTONIC
for chrono::steady_clock.
pthread_cond_clockwait() is implemented in glibc (2.30 and later) and
Android's bionic (Android API version 30 and later).
This change additionally makes wait_for() and wait_until() with clocks
other than chrono::system_clock use CLOCK_MONOTONIC.<Paste>
llvm-svn: 372016
exceptions are disabled.
The patch was reverted due to some confusion about non-movable types. ie
types
that explicitly delete their move constructors. However, such types do
not meet
the requirement for `MoveConstructible`, which is required by
`std::vector`:
Summary:
`std::vector<T>` is free choose between using copy or move operations
when it
needs to resize. The standard only candidates that the correct exception
safety
guarantees are provided. When exceptions are disabled these guarantees
are
trivially satisfied. Meaning vector is free to optimize it's
implementation by
moving instead of copying.
This patch makes `std::vector` unconditionally move elements when
exceptions are
disabled. This optimization is conforming according to the current
standard wording.
There are concerns that moving in `-fno-noexceptions`mode will be a
surprise to
users. For example, a user may be surprised to find their code is slower
with
exceptions enabled than it is disabled. I'm sympathetic to this
surprised, but
I don't think it should block this optimization.
Reviewers: mclow.lists, ldionne, rsmith
Reviewed By: ldionne
Subscribers: zoecarver, christof, dexonsmith, libcxx-commits
Tags: #libc
Differential Revision: https://reviews.llvm.org/D62228
llvm-svn: 371867
Summary:
In https://svnweb.freebsd.org/changeset/base/351659 @emaste removed gets() from
FreeBSD 13's libc, and our copies of libc++ and libstdc++. In that change, the
declarations were simply deleted, but I would like to propose this conditional
test instead.
Reviewers: EricWF, mclow.lists, emaste
Reviewed By: mclow.lists
Subscribers: krytarowski, christof, ldionne, emaste, libcxx-commits
Differential Revision: https://reviews.llvm.org/D67316
llvm-svn: 371324
Summary:
This patch is an exact duplicate of https://reviews.llvm.org/D65609, except
that it uses the newly introduced testing framework to detect if gdb is present
so that the tests won't fail on machines without gdb.
Reviewers: echristo, EricWF
Subscribers: christof, ldionne, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67238
llvm-svn: 371131
This reverts r370502, which broke the use case of a copy-only T (with a
deleted move constructor) when exceptions are disabled. Until we figure
out the right behavior, I'm reverting the commit.
llvm-svn: 371068
The visibility annotations in libc++ are not quite right for GCC, which
results in symbols not being exported when -fvisibility=hidden is used.
To fix the GCC build bots, this commit reverts to the previous state of
not building with hidden visibility on GCC.
In the future, we can build with hidden visibility all the time and
export symbols explicitly using a list. See https://llvm.org/D66970
for one take at this.
llvm-svn: 370926
This is needed anytime we need to clamp an arbitrary floating point
value to an integer type.
Thanks to Eric Fiselier for the patch.
Differential Revision: https://reviews.llvm.org/D66836
llvm-svn: 370891
An upcoming change in Clang will flag _Atomic as being a C11 extension.
To avoid generating this warning in libc++, this commit marks the only
use of _Atomic with the __extension__ extension, which suppresses such
warnings.
llvm-svn: 370796
This patch fixes some typos and other small errors in
directory_iterator.cpp that prevented this file from being compiled for
Win32.
Patch by Stefan Schmidt <thrimbor.github@gmail.com>!
Differential Revision: https://reviews.llvm.org/D66986
llvm-svn: 370599
Summary: Also add a test suite.
Reviewers: EricWF
Subscribers: christof, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65609
Run a pep8 formatter.
Run pep8 formatter.
Convert to PEP8, address other comments from code review.
llvm-svn: 370551
Summary:
`std::vector<T>` is free choose between using copy or move operations when it needs to resize. The standard only candidates that the correct exception safety guarantees are provided. When exceptions are disabled these guarantees are trivially satisfied. Meaning vector is free to optimize it's implementation by moving instead of copying.
This patch makes `std::vector` unconditionally move elements when exceptions are disabled.
This optimization is conforming according to the current standard wording.
There are concerns that moving in `-fno-noexceptions`mode will be a surprise to users. For example, a user may be surprised to find their code is slower with exceptions enabled than it is disabled. I'm sympathetic to this surprised, but I don't think it should block this optimization.
Reviewers: mclow.lists, ldionne, rsmith
Reviewed By: ldionne
Subscribers: zoecarver, christof, dexonsmith, libcxx-commits
Tags: #libc
Differential Revision: https://reviews.llvm.org/D62228
llvm-svn: 370502
Since we build the library with -fvisibility=hidden, the shared object
wouldn't contain __vector_base_common<true>::__throw_length_error()
and __vector_base_common<true>::__throw_out_of_range(), leading to
link errors. This only happened on GCC for some reason.
https://llvm.org/PR43140
llvm-svn: 370240
Louis Dionne