Summary:
This patch implements https://wg21.link/P0325.
Please mind that at it is my first contribution to libc++, so I may have forgotten to abide to some conventions.
Reviewers: EricWF, mclow.lists, ldionne, lichray
Reviewed By: ldionne, lichray
Subscribers: lichray, dexonsmith, zoecarver, christof, ldionne, libcxx-commits
Tags: #libc
Differential Revision: https://reviews.llvm.org/D69882
libcxx/test/std/containers/sequences/array/at.pass.cpp
Need to include <stdexcept> for std::out_of_range.
libcxx/test/std/localization/locale.categories/category.time/*
Need to include <ios> for std::ios.
[libcxx] [test] Calling min and max on an empty valarray is UB.
libcxx/test/std/numerics/numarray/template.valarray/valarray.members/min.pass.cpp
libcxx/test/std/numerics/numarray/template.valarray/valarray.members/max.pass.cpp
The calls `v1.min();` and `v1.max();` were emitting nodiscard warnings
with MSVC's STL. Upon closer inspection, these calls were triggering
undefined behavior. N4842 [valarray.members] says:
"T min() const;
8 Preconditions: size() > 0 is true.
T max() const;
10 Preconditions: size() > 0 is true."
As these tests already provide coverage for non-empty valarrays
(immediately above), I've simply deleted the code for empty valarrays.
[libcxx] [test] Add macros to msvc_stdlib_force_include.h (NFC).
libcxx/test/support/msvc_stdlib_force_include.h
These macros are being used by:
libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/result_of11.pass.cpp
Defining them to nothing allows that test to pass.
[libcxx] [test] Silence MSVC warning C5063 for is_constant_evaluated (NFC).
libcxx/test/std/utilities/meta/meta.const.eval/is_constant_evaluated.pass.cpp
This test is intentionally writing code that MSVC intentionally warns
about, so the warning should be silenced.
Additionally, comment an endif for clarity.
[libcxx] [test] Silence MSVC warning C4127 (NFC).
libcxx/test/support/charconv_test_helpers.h
MSVC avoids emitting this warning when it sees a single constexpr value
being tested, but this condition is a mix of compile-time and run-time.
Using push-disable-pop is the least intrusive way to silence this.
[libcxx] [test] Silence MSVC truncation warning (NFC).
libcxx/test/std/containers/sequences/vector/vector.cons/construct_iter_iter.pass.cpp
This test is intentionally truncating float to int, which MSVC
intentionally warns about, so push-disable-pop is necessary.
[libcxx] [test] Avoid truncation warnings in erase_if tests (NFC).
libcxx/test/std/containers/associative/map/map.erasure/erase_if.pass.cpp
libcxx/test/std/containers/associative/multimap/multimap.erasure/erase_if.pass.cpp
libcxx/test/std/containers/unord/unord.map/erase_if.pass.cpp
libcxx/test/std/containers/unord/unord.multimap/erase_if.pass.cpp
These tests use maps with `short` keys and values, emitting MSVC
truncation warnings from `int`. Adding `static_cast` to `key_type`
and `mapped_type` avoids these warnings.
As these tests require C++20 mode (or newer), for brevity I've changed
the multimap tests to use emplace to initialize the test data.
This has no effect on the erase_if testing.
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
Some tests #include <iostream> but they don't use anything from the
header. Those are probably artifacts of when the tests were developped.
llvm-svn: 357181
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
Summary:
Starting in Clang 8.0 and GCC 8.0, `alignof` and `__alignof` return different values in same cases. Specifically `alignof` and `_Alignof` return the minimum alignment for a type, where as `__alignof` returns the preferred alignment. libc++ currently uses `__alignof` but means to use `alignof`. See llvm.org/PR39713
This patch introduces the macro `_LIBCPP_ALIGNOF` so we can control which spelling gets used.
This patch does not introduce any ABI guard to provide the old behavior with newer compilers. However, if we decide that is needed, this patch makes it trivial to implement.
I think we should commit this change immediately, and decide what we want to do about the ABI afterwards.
Reviewers: ldionne, EricWF
Reviewed By: ldionne, EricWF
Subscribers: jyknight, christof, libcxx-commits
Differential Revision: https://reviews.llvm.org/D54814
llvm-svn: 351289
We already have a specialization that will use memcpy for construction
of trivial types from an iterator range like
std::vector<int>(int *, int *);
But if we have const-ness mismatch like
std::vector<int>(const int *, const int *);
we would use a slow path that copies each element individually. This change
enables the optimal specialization for const-ness mismatch. Fixes PR37574.
Contributions to the patch are made by Arthur O'Dwyer, Louis Dionne.
rdar://problem/40485845
Reviewers: mclow.lists, EricWF, ldionne, scanon
Reviewed By: ldionne
Subscribers: christof, ldionne, howard.hinnant, cfe-commits
Differential Revision: https://reviews.llvm.org/D48342
llvm-svn: 350583
The standard section [array.zero] requires the return value of begin()
and end() methods of a zero-sized array to be unique. Eric Fiselier
clarifies: "That unique value cannot be null, and must be properly aligned".
This patch adds checks for the first part of this clarification: unique
value returned by these methods cannot be null.
Reviewed as https://reviews.llvm.org/D55366.
Thanks to Andrey Maksimov for the patch.
llvm-svn: 348509
The section array.zero says: "The return value of data() is unspecified".
This patch marks all checks of the array<T, 0>.data() return value as
libc++ specific.
Reviewed as https://reviews.llvm.org/D55364.
Thanks to Andrey Maksimov for the patch.
llvm-svn: 348485
This reverts commit 087f065cb0c7463f521a62599884493aaee2ea12.
The tests were failing on 32 bit builds, and I don't have time
to clean them up right now. I'll recommit tomorrow with fixed tests.
llvm-svn: 347816
Summary:
Starting in Clang 8.0 and GCC 8.0, `alignof` and `__alignof` return different values in same cases. Specifically `alignof` and `_Alignof` return the minimum alignment for a type, where as `__alignof` returns the preferred alignment. libc++ currently uses `__alignof` but means to use `alignof`. See llvm.org/PR39713
This patch introduces the macro `_LIBCPP_ALIGNOF` so we can control which spelling gets used.
This patch does not introduce any ABI guard to provide the old behavior with newer compilers. However, if we decide that is needed, this patch makes it trivial to implement.
I think we should commit this change immediately, and decide what we want to do about the ABI afterwards.
Reviewers: ldionne, EricWF
Reviewed By: EricWF
Subscribers: christof, libcxx-commits
Differential Revision: https://reviews.llvm.org/D54814
llvm-svn: 347787
The iterator types for different specializations of containers with the
same element type but different allocators are not required to be
convertible. This patch makes the test to take the iterator type from
the same container specialization as the created container.
Reviewed as https://reviews.llvm.org/D54806.
Thanks to Andrey Maksimov for the patch.
llvm-svn: 347423
Some tests use type std::max_align_t, but don't include <cstddef> header
directly. As a result, these tests won't compile against some conformant
libraries.
Reviewed as https://reviews.llvm.org/D54645.
Thanks to Andrey Maksimov for the patch.
llvm-svn: 347232
This was implicitly converting [1, 3] to bool, which triggers
an MSVC warning. The test should just pass `true`, which is
simpler, has the same behavior, and avoids the warning. (This
is a library test, not a compiler test, and the conversion happens
before calling `push_back`, so passing [1, 3] isn't interesting
in any way. This resembles a previous change to stop passing
`1 == 1` in the `vector<bool>` tests.)
llvm-svn: 346910
Michael Park