These [[nodiscard]] annotations are added as a conforming extension;
it's unclear whether the paper will actually be adopted and make them
mandatory, but they do seem like good ideas regardless.
https://isocpp.org/files/papers/D2351R0.pdf
This patch implements the paper's effect on:
- std::to_integer, std::to_underlying
- std::forward, std::move, std::move_if_noexcept
- std::as_const
- std::identity
The paper also affects (but libc++ does not yet have an implementation of):
- std::bit_cast
Differential Revision: https://reviews.llvm.org/D99895
After this patch, we can use `--param std=c++20` even if the compiler only
supports -std=c++2a. The test suite will handle that for us. The only Lit
feature that isn't fully baked will always be the "in development" one,
since we don't know exactly what year the standard will be ratified in.
This is another take on https://reviews.llvm.org/D99789.
Differential Revision: https://reviews.llvm.org/D100210
Use `_LIBCPP_TEMPLATE_VIS` instead of `_LIBCPP_TYPE_VIS` for a template
class.
This fixes the nodiscard_extensions.pass.cpp and a couple
func.search.default test cases when built in MSVC/DLL configurations.
Differential Revision: https://reviews.llvm.org/D99932
This doesn't fail when _LIBCPP_HAS_NO_INT128 is defined consistently
in both CMAKE_CXX_FLAGS and LIBCXX_TEST_COMPILER_FLAGS; the XFAIL was
added based on early CI testruns where that flag was missing in
LIBCXX_TEST_COMPILER_FLAGS.
Differential Revision: https://reviews.llvm.org/D99705
This will avoid typos like `_LIBCPP_STD_VERS` (<future>) or using `#if TEST_STD_VER > 17` without including "test_macros.h".
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D99515
Because the constexpr-time codepath triggers a Clang bug. It seems
that Clang compiles it okay in release mode, but when Clang itself
is compiled in debug mode (with assertions turned on), this input
triggers an assertion failure in Clang itself. See comments on D96385
and Clang bug report https://bugs.llvm.org/show_bug.cgi?id=45879
This commit should get the debug-mode buildbots back to green.
This patch changes the variant even in pre-C++2b.
It should not break anything, only allow use cases that didn't work previously.
Notes:
`__as_variant` is used in `__visitation::__variant::__visit_alt`, but I haven't used it in `__visitation::__variant::__visit_alt_at`.
That's because it is used only in `__visit_value_at`, which in turn is always used on variant specializations (that's in comparison operators).
* https://wg21.link/P2162
Reviewed By: ldionne, #libc, Quuxplusone
Differential Revision: https://reviews.llvm.org/D97394
This makes no attempt yet to look into the why/what for each of them,
but makes the CI configuration useful for tracking further regressions.
After looking into each case, they can either be fixed, or converted
into UNSUPPORTED: windows or XFAIL: windows, once the cause is known
and explained.
A number of the filesystem cases can be fixed by patches that are
currently in review.
Differential Revision: https://reviews.llvm.org/D99095
In previous versions of clang, __is_signed and __is_unsigned builtins did not
correspond to is_signed and is_unsigned behaviour for enums. The builtins were
fixed in D67897 and D98104.
* Disable the fast path of is_unsigned for clang versions < 13
* Add more tests for is_signed, is_unsigned and is_arithmetic
Differential Revision: https://reviews.llvm.org/D97283
Implements part of P0898R3 Standard Library Concepts
Reworks D74351 to use requires-clauses over SFINAE and so that it more
closely follows the wording.
Co-authored by: Michael Schellenberger Costa <mschellenbergercosta@googlemail.com>
(Michael did all the heavy lifting and I came in to polish it for
submission, since Michael is focussing on `std::format` now.)
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D96657
The implementation of tuple's constructors and assignment operators
currently diverges from the way the Standard specifies them, which leads
to subtle cases where the behavior is not as specified. In particular, a
class derived from a tuple-like type (e.g. pair) can't be assigned to a
tuple with corresponding members, when it should. This commit re-implements
the assignment operators (BUT NOT THE CONSTRUCTORS) in a way much closer
to the specification to get rid of this bug. Most of the tests have been
stolen from Eric's patch https://reviews.llvm.org/D27606.
As a fly-by improvement, tests for noexcept correctness have been added
to all overloads of operator=. We should tackle the same issue for the
tuple constructors in a future patch - I'm just trying to make progress
on fixing this long-standing bug.
PR17550
rdar://15837420
Differential Revision: https://reviews.llvm.org/D50106
This patch ensures that SFINAE is used to delete assignment operators in pair and tuple based on issue 2729.
Differential Review: https://reviews.llvm.org/D62454
This patch implements 2802. Requires _Deleter to have call operator and be move constructible. Based on D62233.
Refs PR37637.
Differential Revision: https://reviews.llvm.org/D62274
Implements parts of:
- P0645 Text Formatting
Depends on D92214
Reland with changes:
The format header will only be compiled if the compiler used has support
for concepts. This should fix the issues with the initial version.
Differential Revision: https://reviews.llvm.org/D93166
Implement the resolution of LWG2993. Replace a deleted constructor
with a constructor that SFINAEs away in appropriate circumstances.
Also, now that the constructor is templated, we must have an
explicit deduction guide to make CTAD work.
Some tests have been merged in from Agustín Bergé's D40259.
Differential Revision: https://reviews.llvm.org/D92725
This reverts commit 35a57f39b5.
A build is broken during clang bootstrap with:
In file included from ../libcxx/src/format.cpp:9:
/tmp/ci-nGNyLRM9V3/include/c++/v1/format:153:16: error: no member named 'is_constant_evaluated' in namespace 'std::__1'
if (_VSTD::is_constant_evaluated() && __id >= __num_args_)
~~~~~~~^
1 error generated.
This is the first step at implementing <format>. It adds the <format> header
and implements the `format_error`. class.
Implemnts parts of:
-P0645 Text Formatting
Reviewed By: ldionne, #libc, miscco, curdeius
Differential Revision: https://reviews.llvm.org/D92214
LWG reflector consensus is that this was a bug in libc++.
(In particular, MSVC also will fix it in their STL, soon.)
Bug originally discovered by Logan Smith.
Also fix `std::function<const void()>`, which should work
the same way as `std::function<void()>` in terms of allowing
"conversions" from non-void types.
Differential Revision: https://reviews.llvm.org/D94452
Previously, LIBCXX_ENABLE_FILESYSTEM controlled only whether the filesystem
support was compiled into libc++'s library. This commit promotes the
setting to a first-class option like LIBCXX_ENABLE_LOCALIZATION, where
the whole library is aware of the setting and features that depend on
<filesystem> won't be provided at all. The test suite is also properly
annotated such that tests that depend on <filesystem> are disabled when
the library doesn't support it.
This is an alternative to https://llvm.org/D94824, but also an improvement
along the lines of LIBCXX_ENABLE_LOCALIZATION that I had been wanting to
make for a while.
Differential Revision: https://reviews.llvm.org/D94921
This patch updates `allocate_shared` to call `allocator_traits::construct`
when creating the object held inside the shared_pointer, and
`allocator_traits::destroy` when destroying it. This resolves
the part of P0674R1 that was originally filed as LWG2070.
This change is landed separately from the rest of P0674R1 because it is
incredibly tricky from an ABI perspective.
This is the reason why this change is so tricky is that we previously
used EBO in a compressed pair to store both the allocator and the object
type stored in the `shared_ptr`. However, starting in C++20, P0674
requires us to use Allocator construction for initializing the object type.
That requirement rules out the use of the EBO for the object type, since
using the EBO implies that the base will be initialized when the control
block is initialized (and hence we can't do it through Allocator construction).
Hence, supporting P0674 requires changing how we store the object type
inside the control block, which we do while being ABI compatible by using
some trickery with a properly aligned char buffer.
Fixes https://llvm.org/PR41900
Supersedes https://llvm.org/D62760
Differential Revision: https://reviews.llvm.org/D91201
"LLVM Buildbot on libcxx-libcxxabi-x86_64-linux-debian" is not happy
with default-initializing the `double` member of `A` in a constexpr
function. At least I'm pretty sure that's what it's complaining about.
When the allocator is only explicitly convertible from other specializations
of itself, the new version of std::allocate_shared would not work because
it would try to do an implicit conversion. This patch fixes the problem
and adds a test so that we don't fall into the same trap in the future.
Checking that `T` is constructible from `Args...` is technically not
required by the Standard, although any implementation will obviously
error out if that's not satisfied. However, this check is incompatible
with using Allocator construction in the control block (upcoming change
as part of implementing P0674), so I'm removing it now to reduce the
upcoming diff as much as possible.
Differential Revision: https://reviews.llvm.org/D93246
- std::reference_wrapper
- std::function
- std::mem_fn
While I'm here, remove _VSTD:: qualification from calls to `declval`
because it takes no arguments and thus isn't susceptible to ADL.
Differential Revision: https://reviews.llvm.org/D92884
This simplifies the implementation, and it appears to be equivalent since
make_shared was allocating memory with std::allocator anyway.
Differential Revision: https://reviews.llvm.org/D93071
This will fix remaining failures on gcc-9 buildbot: http://lab.llvm.org:8011/#/builders/101.
gcc-8 and gcc-9 do not support constexpr destructors nor constexpr allocation.
Fix gcc warnings: -Wconversion, -Wpragmas.
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
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
This undefined behavior was found by applying Lénárd Szolnoki's proposal
to disable implicit conversion of default_delete<D> to default_delete<B>.
The offending part of the test is circa line 243.
The wording that makes it undefined behavior is http://eel.is/c++draft/expr.delete#3 .
Differential Revision: https://reviews.llvm.org/D90536
- Several -Wshadow warnings
- Several places where we did not initialize our base class explicitly
- Unused variable warnings
- Some tautological comparisons
- Some places where we'd pass null arguments to functions expecting
non-null (in unevaluated contexts)
- Add a few pragmas to turn off spurious warnings
- Fix warnings about declarations that don't declare anything
- Properly disable deprecation warnings in ext/ tests (the pragmas we
were using didn't work on GCC)
- Disable include_as_c.sh.cpp because GCC complains about C++ flags
when compiling as C. I couldn't find a way to fix this one properly,
so I'm disabling the test. This isn't great, but at least we'll be
able to enable warnings in the whole test suite with GCC.
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
It appears that the released version of clang that supports constexpr
destructors is clang 10 and the oldest one that accepts -std=c++2a is 5,
so mark these as UNSUPPORTED for clang-5 to clang-9.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D89704
Also, some tests had multiple death tests in them, so split them into
separate tests instead. The second death test would obviously never
get run, because the first one would kill the program before.
This is needed when running the tests in Freestanding mode, where main()
isn't treated specially. In Freestanding, main() doesn't get mangled as
extern "C", so whatever runtime we're using fails to find the entry point.
One way to solve this problem is to define a symbol alias from __Z4mainiPPc
to _main, however this requires all definitions of main() to have the same
mangling. Hence this commit.
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.
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
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.
This implements the part of P0619R4 related to the default allocator.
This is incredibly important, since otherwise there is an ABI break
between C++17 and C++20 w.r.t. the default allocator's size_type on
platforms where std::size_t is not the same as std::make_unsigned<std::ptrdiff_t>.
We don't support GCC in C++03 mode, and Clang provides rvalue references
even in C++03 mode. So there's effectively no supported compiler that
doesn't support rvalue references.
Differential Revision: https://reviews.llvm.org/D84943
Add shared_ptr tests where the element type and pointer type aren't 'convertible' but are 'compatible'.
Responding to a comment from D81414.
Differential Revision: https://reviews.llvm.org/D81532
Some time ago, I introduced shortcut features like dylib-has-no-shared_mutex
to encode whether the deployment target supported shared_mutex (say). This
made the test suite annotations cleaner.
However, the problem with building Lit features on top of other Lit
features is that it's easier for them to become stale, especially when
they are generated programmatically. Furthermore, it makes the bar for
defining configurations from scratch higher, since more features have
to be defined. Instead, I think it's better to put the XFAILs in the
tests directly, which allows cleaning them up with a simple grep.
This reverts commit 0c148430cf, which added an assertion in day().
The Standard doesn't allow day() to crash -- instead it says that the
result is unspecified.
Differential Revision: https://reviews.llvm.org/D70346
All compilers supported by libc++ have rvalues in C++03 mode so, there is no need for this non-rvalue overload.
Differential Revision: https://reviews.llvm.org/D80881
C++98 and C++03 are effectively aliases as far as Clang is concerned.
As such, allowing both std=c++98 and std=c++03 as Lit parameters is
just slightly confusing, but provides no value. It's similar to allowing
both std=c++17 and std=c++1z, which we don't do.
This was discovered because we had an internal bot that ran the test
suite under both c++98 AND c++03 -- one of which is redundant.
Differential Revision: https://reviews.llvm.org/D80926
The tests had copy-paste errors which started showing when an
unused-variable warning started being emitted after we made
the MoveOnly type constexpr (in a4b8ee6422).
* improve coverage in `span`'s "conversion from `std::array`" test, while eliminating MSVC diagnostics about `testConstructorArray<T>() && testConstructorArray<const T, T>()` being redundant when `T` is already `const`.
* Remove use of `is_assignable` that triggers UB due to an insufficiently-complete type argument in `std::function`'s assignment operator test.
* Don't test that `shared_ptr` initialization from an rvalue triggers the lvalue aliasing constructor on non-libc++; this is not the case for Standard Libraries that implement LWG-2996. (Ditto, I'd simply remove this but it's your library ;).)
Differential Revision: https://reviews.llvm.org/D80030
Implements P0414R2:
* Adds support for array types in std::shared_ptr.
* Adds reinterpret_pointer_cast for shared_ptr.
Re-committing now that the leaking tests are fixed.
Differential Revision: https://reviews.llvm.org/D62259
Implements P0414R2:
* Adds support for array types in std::shared_ptr.
* Adds reinterpret_pointer_cast for shared_ptr.
Differential Revision: https://reviews.llvm.org/D62259
This patch adds deduction guides to <memory> to allow deducing
construction of shared_ptrs from unique_ptrs, and from weak_ptrs
and vice versa, as specified by C++17.
Differential Revision: https://reviews.llvm.org/D69603
Tests that require support for Clang-verify are already marked as such
explicitly by their extension, which is .verify.cpp. Requiring the use
of an explicit Lit feature is, after thought, not really helpful.
This is a change in design: we have been bitten in the past by tests not
being enabled when we thought they were. However, the issue was mostly
with file extensions being ignored. The fix for that is not to blindly
require explicit features all the time, but instead to report all files
that are in the suite but that don't match any known test format. This
can be implemented in a follow-up patch.