Commit Graph

3251 Commits

Author SHA1 Message Date
Martin Storsjö 8a783e6845 [libcxx] Implement is_absolute properly for windows
Differential Revision: https://reviews.llvm.org/D91177
2021-02-17 19:33:05 +02:00
Arthur O'Dwyer 5f58374bbe [libc++] Change `std::numeric_limits` to just `numeric_limits` in <chrono>.
The namespace is unnecessary, and libc++ style is not to include it on type names.
(As opposed to function names, where qualification affects ADL; and in certain
function signatures where `std::` and `_VSTD::` might be mangled differently.
This is none of those situations.)
2021-02-15 16:12:10 -05:00
Louis Dionne 5d0d465ad4 [libc++] Mark __cpp_lib_constexpr_memory as being implemented 2021-02-15 15:26:53 -05:00
Zbigniew Sarbinowski 48fcce1aea [SystemZ][ZOS] Fix __libcpp_thrad_isnull()
Previous pthread revision https://reviews.llvm.org/D91875 missed a small change for `__libcpp_thrad_isnull()` required for z/OS.

Reviewed By: zibi

Differential Revision: https://reviews.llvm.org/D96302
2021-02-12 20:21:11 +00:00
Zbigniew Sarbinowski cb2d2ae56a [SystemZ][ZOS] Provide CLOCK_MONOTONIC alternative
We need CLOCK_MONOTONIC equivalent implementation for z/OS within libc++. The default implementation is asserting.

On z/OS the lack of  'clock_gettime()' and 'time_point()' force us to look for alternatives.
The current proposal is to use `gettimeofday()` for CLOCK_MONOTONIC  which is also used in CLOCK_REALTIME.  This will allow us to skip the assertion with compromised CLOCK_MONOTONIC implementation which will not guarantee to never go back in time because it will use `gettimeofday()` but only when it's set.

Is this a good compromise for platforms which does not support monotonic clock?
Hopefully this will spark the discussion and agreement how to proceed in this situation.

Reviewed By: #libc, ldionne, hubert.reinterpretcast

Differential Revision: https://reviews.llvm.org/D93542
2021-02-12 18:39:48 +00:00
Mark de Wever f8772da8cc [libc++][format] Enable format_error on older compilers.
It seems like modifying the header doesn't cause libc++ to be rebuild.
So the breakage of the previous commit didn't happen on my system.

This should fix the build of https://buildkite.com/mlir/mlir-core
2021-02-11 19:11:20 +01:00
Mark de Wever af83e89ae3 [libc++][format] Improve Add basic_format_parse_context.
Add an additional guard to prevent building on older clang versions.

This should fix the build of https://buildkite.com/mlir/mlir-core
2021-02-11 18:55:54 +01:00
Mark de Wever 38ddeade65 [libc++][format] Add basic_format_parse_context.
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
2021-02-11 17:57:54 +01:00
Ilya Tokar c81d52997a [libc++] Use builtins in more math.h functions.
Not using builtins doesn't always imply worse code,
but for e. g. isinf, this is 30%+ faster.

Before:
name        time/op
BM_isinf     2.14ns ± 2%

After:
name        time/op
BM_isinf     1.33ns ± 2%

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D88854
2021-02-10 15:17:42 -05:00
Christopher Di Bella 17db24a7a8 [libcxx] adds concepts `std::invocable` and `std::regular_invocable`
Implements parts of:
    - P0898R3 Standard Library Concepts
    - P1754 Rename concepts to standard_case for C++20, while we still can

Differential Revision: https://reviews.llvm.org/D96235
2021-02-10 19:35:53 +00:00
Christopher Di Bella c63de225fd [libcxx] adds concept std::derived_from
Implements parts of:
    - P0898R3 Standard Library Concepts
    - P1754 Rename concepts to standard_case for C++20, while we still can

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D74292
2021-02-10 19:30:08 +00:00
Christopher Di Bella bee7b07f23 [libcxx] adds [concepts.arithmetic]
Implements parts of:
    * P0898R3 Standard Library Concepts
    * P1754 Rename concepts to standard_case for C++20, while we still can

Differential Revision: https://reviews.llvm.org/D88131
2021-02-10 19:04:57 +00:00
Christopher Di Bella 2193e8be3e [libcxx] adds concept `std::copy_constructible`
Implements parts of:
    - P0898R3 Standard Library Concepts
    - P1754 Rename concepts to standard_case for C++20, while we still can

Depends on D96230

Differential Revision: https://reviews.llvm.org/D96232
2021-02-10 17:56:42 +00:00
Christopher Di Bella 2b2f36a8b1 [libcxx] adds concept `std::move_constructible`
Implements parts of:
    - P0898R3 Standard Library Concepts
    - P1754 Rename concepts to standard_case for C++20, while we still can

Depends on D77961

Differential Revision: https://reviews.llvm.org/D96230
2021-02-10 17:33:35 +00:00
Colin Finck ebfadd82cb [libc++] Fix copy-paste mistake in __threading_support
Differential Revision: https://reviews.llvm.org/D96115
2021-02-10 11:00:32 -05:00
Christopher Di Bella 8caf835337 [libcxx] adds concept `std::convertible_to`
Implements parts of:
    - P0898R3 Standard Library Concepts
    - P1754 Rename concepts to standard_case for C++20, while we still can

Differential Revision: https://reviews.llvm.org/D77961
2021-02-10 03:27:41 +00:00
Arthur O'Dwyer eec04092d6 [libc++] [LWG2993] reference_wrapper<T> conversion from U&&
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
2021-02-09 15:50:25 -05:00
zoecarver dea74b2820 [libc++] Add `noexcept` to `string::find` and similar members.
Adds `noexcept` to `string_view`/`string::find` and similar members
(`rfind`, etc.). See discussion in D95251. Refs D95821.

Reviewed By: curdeius, ldionne

Differential Revision: https://reviews.llvm.org/D95848
2021-02-09 11:47:40 -08:00
Arthur O'Dwyer 85167fb7c2 [libc++] Further improve the contiguous-iterator story, and fix some bugs.
- Quality-of-implementation: Avoid calling __unwrap_iter in constexpr contexts.
    The user might conceivably write a contiguous iterator where normal iterator
    arithmetic is constexpr-friendly but `std::to_address(it)` isn't.

- Bugfix: When you pass contiguous iterators to `std::copy`, you should get
    back your contiguous iterator type, not a raw pointer. That means that
    libc++ can't `__unwrap_iter` unless it also does `__rewrap_iter`.
    Fortunately, this is implementable.

- Improve test coverage of the new `contiguous_iterator` test iterator.
    This catches the bug described above.

- Tests: Stop testing that we can `std::copy` //into// an `input_iterator`.
    Our test iterators may currently support that, but it seems nonsensical to me.

Differential Revision: https://reviews.llvm.org/D95983
2021-02-05 15:18:04 -05:00
Arthur O'Dwyer 5d9565634c Revert "Revert "[libc++] [P0879] constexpr std::nth_element, and rewrite its tests.""
This reverts commit b6ffece320.

The bug is now fixed (it was a stupid cut-and-paste kind of error),
and the regression test added. The new patch is also simpler than the old one!

Differential Revision: https://reviews.llvm.org/D96084
2021-02-05 12:02:43 -05:00
Jordan Rupprecht b6ffece320 Revert "[libc++] [P0879] constexpr std::nth_element, and rewrite its tests."
This reverts commit 207d4be4d9 due to returning incorrect results. Regression test case posted in D96074.
2021-02-04 14:03:49 -08:00
Louis Dionne 1700ea7302 [libc++] Remove the ability to use braced-init for filesystem paths
According to my reading of http://eel.is/c++draft/filesystems#fs.class.path,
the Standard doesn't actually mention that this should work. Since other
implementations don't allow it, allowing it in libc++ is just setting a
portability trap.

Supersedes https://reviews.llvm.org/D89865.

Differential Revision: https://reviews.llvm.org/D95975
2021-02-04 11:49:00 -05:00
Louis Dionne 76fc35752d [libc++] Make feature-test macros consistent with availability macros
Before this patch, feature-test macros didn't take special availability
markup into account, which means that feature-test macros can sometimes
appear to "lie". For example, if you compile in C++20 mode and target
macOS 10.13, the __cpp_lib_filesystem feature-test macro will be provided
even though the <filesystem> declarations are marked as unavailable.
This patch fixes that.

rdar://68142369

Differential Revision: https://reviews.llvm.org/D94983
2021-02-04 11:40:22 -05:00
Louis Dionne b51756819a [libc++] Rename include/support to include/__support
We do ship those headers, so the directory name should not be something
that can potentially conflict with user-defined directories.

Differential Revision: https://reviews.llvm.org/D95956
2021-02-04 10:16:33 -05:00
Arthur O'Dwyer 493f140792 [libc++] [P0879] constexpr std::sort
This completes libc++'s implementation of
P0879 "Constexpr for swap and swap related functions."
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0879r0.html

For the feature-macro adjustment, see
https://cplusplus.github.io/LWG/issue3256

Differential Revision: https://reviews.llvm.org/D93661
2021-02-03 18:57:05 -05:00
Arthur O'Dwyer d41c6d51cb [libc++] Rationalize our treatment of contiguous iterators and __unwrap_iter().
- Implement C++20's changes to `reverse_iterator`, so that it won't be
    accidentally counted as a contiguous iterator in C++20 mode.
- Implement C++20's changes to `move_iterator` as well.
- `move_iterator` should not be contiguous. This fixes a bug where
    we optimized `std::copy`-of-move-iterators in an observable way.
    Add a regression test for that bugfix.
- Add libcxx tests for `__is_cpp17_contiguous_iterator` of all relevant
    standard iterator types. Particularly check that vector::iterator
    is still considered contiguous in all C++ modes, even C++03.

After this patch, there continues to be no supported way to write your
own iterator type in C++17-and-earlier such that libc++ will consider it
"contiguous"; however, we now fully support the C++20 approach (in C++20
mode only). If you want user-defined contiguous iterators in C++17-and-earlier,
libc++'s position is "please upgrade to C++20."

Differential Revision: https://reviews.llvm.org/D94807
2021-02-03 16:28:38 -05:00
Reid Kleckner bab7486416 Disable CFI in __get_elem to allow casting a pointer to uninitialized memory
Fixes usage of shared_ptr with CFI enabled, which is llvm.org/pr48993.

Differential Revision: https://reviews.llvm.org/D95827
2021-02-02 12:39:24 -08:00
Mehdi Amini 68f66f37d7 Revert "[libc++][format] Add basic_format_parse_context."
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.
2021-02-01 21:18:11 +00:00
Mark de Wever 35a57f39b5 [libc++][format] Add basic_format_parse_context.
Implements parts of:
- P0645 Text Formatting

Depends on D92214

Reviewed By: ldionne, curdeius, #libc

Differential Revision: https://reviews.llvm.org/D93166
2021-02-01 20:19:20 +01:00
Mark de Wever 3ffc53ba16 [libc++] Implements concept default_initializable.
Implements:
- LWG3149 DefaultConstructible should require default initialization

Implements parts of:
 - P0898R3 Standard Library Concepts
 - P1754 Rename concepts to standard_case for C++20, while we still can

Depends on D91986

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D93461
2021-02-01 19:13:24 +01:00
Ruslan Arutyunyan c448ea948c [libc++] Fix for the Bug 41784
Add deleted volatile copy-assignment operator in the most derived atomic
to fix the Bug 41784. The root cause: there is an `operator=(T) volatile`
that has better match than the deleted copy-assignment operator of the base
class when `this` is `volatile`. The compiler sees that right operand of
the assignment operator can be converted to `T` and chooses that path
without taking into account the deleted copy-assignment operator of the
base class.

The current behavior on libstdc++ is different from what we have in libc++.
On the same test compilation fails with libstdc++. Proof: https://godbolt.org/z/nebPYd
(everything is the same except the -stdlib option).

I choose the way with explicit definition of copy-assignment for atomic
in the most derived class. But probably we can fix that by moving
`operator=(T)` overloads to the base class from both specializations.
At first glance, it shouldn't break anything.

Differential Revision: https://reviews.llvm.org/D90968
2021-02-01 10:14:22 -05:00
Mark de Wever 18fe3fe0e7 [libc++] Implements concept constructible_from
Implements parts of:
- P0898R3 Standard Library Concepts
- P1754 Rename concepts to standard_case for C++20, while we still can

Depends on: D91004

Reviewed By: ldionne, cjdb, #libc

Differential Revision: https://reviews.llvm.org/D91986
2021-01-28 18:32:47 +01:00
Mark de Wever 081c1db02d [libc++] Implement format_error.
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
2021-01-28 18:02:53 +01:00
Arthur O'Dwyer 207d4be4d9 [libc++] [P0879] constexpr std::nth_element, and rewrite its tests.
This patch is more than just adding the `constexpr` keyword, because
the old code relied on `goto`, and `goto` is not constexpr-friendly.
Refactor to eliminate `goto`, and then mark it as constexpr in C++20.

I freely admit that the name `__nth_element_partloop` is bad;
I couldn't find any better name because I don't really know
what this loop is doing, conceptually. Vice versa, I think
`__nth_element_find_guard` has a decent name.

Now the only one we're still missing from P0879 is `sort`.

Differential Revision: https://reviews.llvm.org/D93557
2021-01-28 11:59:00 -05:00
Arthur O'Dwyer 5386aa2627 [libc++] [P0879] constexpr heap and partial_sort algorithms
Now the only ones we're still missing from P0879
are `sort` and `nth_element`.

Differential Revision: https://reviews.llvm.org/D93512
2021-01-27 10:26:06 -05:00
Simon Tatham 7b3ba8dd02 [libcxx] Update include/__libcpp_version to match include/__config
https://reviews.llvm.org/rG5369517d20dd362a178a1b2d6c398d8898ee4620
bumped the version number in __config to 13000, causing a test failure
in libcxx/test/libcxx/libcpp_version.pass.cpp because now the two
don't match.

This is the only part of the post-release TODO in
libcxx/docs/Contributing.rst that wasn't done by that commit.
2021-01-27 15:16:55 +00:00
Tom Stellard 5369517d20 Bump the trunk major version to 13
and clear the release notes.
2021-01-26 19:37:55 -08:00
Arthur O'Dwyer f9b6fd269b [libc++] Support immovable return types in std::function.
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
2021-01-25 19:34:41 -05:00
Nico Weber a206d991f9 libcxx: Try to fix build after D92044 2021-01-25 15:10:41 -05:00
Ruslan Arutyunyan 9d50958757 [libc++] Fix build after 51faba35fd
Differential Revision: https://reviews.llvm.org/D95372
2021-01-25 13:40:47 -05:00
Arthur O'Dwyer f851db3dae [libc++] [P0879] constexpr std::reverse, partition, *_permutation.
After this patch, the only parts of P0879 that remain missing will be
std::nth_element, std::sort, and the heap/partial_sort algorithms.

Differential Revision: https://reviews.llvm.org/D93443
2021-01-25 13:09:30 -05:00
Arthur O'Dwyer 3fbd3eaf28 [libc++] Implement [P0769] "Add shift to algorithm" (shift_left, shift_right)
I believe this is a complete implementation of std::shift_left and std::shift_right from
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0769r2.pdf

Some test cases copied-with-modification from D60027.

Differential Revision: https://reviews.llvm.org/D93819
2021-01-25 12:57:04 -05:00
Ruslan Arutyunyan 51faba35fd [libc++] Implement P0655R1 visit<R>: Explicit Return Type for visit
Differential Revision: https://reviews.llvm.org/D92044
2021-01-25 11:14:45 -05:00
Mark de Wever a8e06361dd [libc++] Implements concept destructible
Implements parts of:
- P0898R3 Standard Library Concepts
- P1754 Rename concepts to standard_case for C++20, while we still can

Reviewed By: ldionne, miscco, #libc

Differential Revision: https://reviews.llvm.org/D91004
2021-01-23 18:17:25 +01:00
Thorsten Schütt b973e2e2f2 [libc++] Introduce __bits
It has the low-level bit fiddling operations from bit. It eliminates a cyclic dependency between __bit_reference, bits, and vector. I want to exploit this in later patches.

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D94908
2021-01-22 21:20:23 +01:00
Brad Smith 1be2524b7d [libcxx] Check return value for asprintf()
local __libcpp_asprintf_l() -> libc asprintf() was inspecting the pointer (with
indeterminate value) for failure, rather than the return value of -1.

Reviewed By: ldionne

Differential Revision: https://reviews.llvm.org/D94564
2021-01-21 19:43:11 -05:00
Wim Leflere 6ac9cb2a7c [libc++][P1679] add string contains
C++23 string contains implementation and tests

Paper: https://wg21.link/P1679R3
Standard (string): https://eel.is/c++draft/string.contains
Standard (string_view): https://eel.is/c++draft/string.view.ops#lib:contains,basic_string_view

Differential Revision: https://reviews.llvm.org/D93912
2021-01-19 14:35:07 -05:00
Louis Dionne 933518fff8 [libc++] Make LIBCXX_ENABLE_FILESYSTEM fully consistent
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
2021-01-19 14:15:48 -05:00
Louis Dionne 68dba7eae1 [libc++] Unbreak the debug mode
When the Debug mode is enabled, we disable extern declarations because we
don't want to use the functions compiled in the library, which might not
have had the debug mode enabled when built. However, some extern declarations
need to be kept, because code correctness depends on it.

31e820378b removed those declarations, which had the unintended
consequence of breaking the debug build. This commit fixes that by
re-introducing a separate macro for the required extern declarations,
and adds a comment so that we don't fall into that trap in the future.

Differential Revision: https://reviews.llvm.org/D94718
2021-01-19 14:15:31 -05:00
Marek Kurdej a11f8b1ad6 [libc++] [P0935] [C++20] Eradicating unnecessarily explicit default constructors from the standard library.
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0935r0.html

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D91292
2021-01-19 08:22:06 +01:00
Louis Dionne 2cb4a96a99 [libc++] NFCI: Refactor allocator_traits
The implementation had a lot of boilerplate and was more complicated than
necessary. This NFC refactoring introduces a few macros to reduce code
duplication, and uses a consistent style and formatting for the whole file.

Differential Revision: https://reviews.llvm.org/D94544
2021-01-18 17:37:25 -05:00
Reid Kleckner 4f24d0dd53 Fix libc++ clang-cl build, swap attribute order
Clang insists that __attribute__ attributes precede __declspec
attributes. This is a longstanding known issue:
https://llvm.org/pr24559. Re-order the visibility and deprecation macros
to fix the build.

Differential Revision: https://reviews.llvm.org/D94788
2021-01-15 11:44:13 -08:00
Shoaib Meenai 0066a09579 [libc++] Give extern templates default visibility on gcc
Contrary to the current visibility macro documentation, it appears that
gcc does handle visibility attribute on extern templates correctly, e.g.
https://godbolt.org/g/EejuV7. We need this so that extern template
instantiations of classes not marked _LIBCPP_TEMPLATE_VIS (e.g.
__vector_base_common) are correctly exported with gcc when building with
hidden visibility.

Reviewed By: ldionne

Differential Revision: https://reviews.llvm.org/D35388
2021-01-12 18:30:56 -08:00
Brad Smith 79f99ba65d [libcxx] Port to OpenBSD
Add initial OpenBSD support.

Reviewed By: ldionne

Differential Revision: https://reviews.llvm.org/D94205
2021-01-12 14:21:11 -05:00
Arthur O'Dwyer eef4bdbb34 [libc++] Add a missing `<_Compare>` template argument.
Sometimes `_Compare` is an lvalue reference type, so letting it be
deduced is pretty much always wrong. (Well, less efficient than
it could be, anyway.)

Differential Revision: https://reviews.llvm.org/D93562
2021-01-12 14:18:24 -05:00
Marek Kurdej 1f1250151f [libc++] [C++2b] [P1048] Add is_scoped_enum and is_scoped_enum_v.
* https://wg21.link/p1048

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D94409
2021-01-12 17:08:20 +01:00
Arthur O'Dwyer ca1694b9d0 Re-enable __cpp_lib_constexpr_functional.
I accidentally disabled this feature-test macro in my D93830,
due to a rebasing conflict. It had been enabled by my D93815,
and should have remained enabled.
2021-01-08 17:30:04 -05:00
Louis Dionne 955dd7b7f3 [libc++] LWG2070: Use Allocator construction for objects created with allocate_shared
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
2021-01-08 13:04:03 -05:00
Marek Kurdej 95729f95d8 [libc++] Add basic support for -std=c++2b.
* Add feature test macros.
* Add buildbot configuration generic-cxx2b that uses clang-tot.

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D94227
2021-01-08 19:02:41 +01:00
Arthur O'Dwyer 466df1718e [libc++] Update generate_feature_test_macro_components.py to match SD-6.
It's still a little confusing because in many cases C++17 and C++20
have different values, and libc++ implements the C++17 behavior but
not the C++20 behavior; 'unimplemented' can't represent that scenario.
Ultimately we probably ought to completely redesign the script to be
in terms of paper numbers, rather than language revisions, and make
it generate the CSV files like "Cxx2aStatusPaperStatus.csv" as well.

Most newly added macros are unimplemented. I've marked a few as implemented,
though, based on my reading of the code; for example I was pretty sure
`__cpp_lib_latch` is implemented since we have `<latch>`.

Differential Revision: https://reviews.llvm.org/D93830
2021-01-08 11:44:39 -05:00
Arthur O'Dwyer ff1b6f9ff2 [libc++] Alphabetize generate_feature_test_macro_components.py. NFCI.
For ease of comparing our list with the official SD-6 list, which is alphabetized.
https://isocpp.org/std/standing-documents/sd-6-sg10-feature-test-recommendations#library-feature-test-macros
This also alphabetizes the lists of headers in which the macros are
defined, which harmlessly alters many comments in <version>.
Also drive-by-fix some trivial flake8 warnings.
2021-01-07 18:11:46 -05:00
Marek Kurdej 044b892c79 [libc++] Use c++20 instead of c++2a consistently.
* The only exception is that the flag -std=c++2a is still used not to break compatibility with older compilers (clang <= 9, gcc <= 9).
* Bump _LIBCPP_STD_VER for C++20 to 20 and use 21 for the future standard (C++2b).

That's a preparation step to add c++2b support to libc++.

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D93383
2021-01-07 13:11:33 +01:00
Martin Storsjö f4485240a2 [libcxx] Handle backslash as path separator on windows
Differential Revision: https://reviews.llvm.org/D91138
2021-01-07 10:02:47 +02:00
Arthur O'Dwyer 781c476ce0 [libc++] ADL-proof vector<bool> by adding _VSTD:: qualification on calls.
This affects only vectors with weird/malicious allocators,
the same corner case covered in D91708, but for `vector<bool>` this time.

Also ADL-proof <__tree>, which affects only sets and maps with weird/malicious
allocators where the ADL trap is in the *fancy pointer type*.

Also drive-by _VSTD:: qualification in the guts of std::bind,
std::packaged_task, std::condition_variable.

Differential Revision: https://reviews.llvm.org/D93424
2021-01-06 18:23:50 -05:00
Arthur O'Dwyer 7b00e9fae3 [libc++] [P1065] Constexpr invoke, reference_wrapper, mem_fn, not_fn, default_searcher.
This completes the implementation of P1065 "constexpr INVOKE":
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1065r2.html

This doesn't yet complete the implementation of P1032 "Misc constexpr bits,"
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1032r1.html
but it does complete all of the <functional> bits, which means
that we can now set `__cpp_lib_constexpr_functional` for C++20.

This could use more constexpr tests for `std::reference_wrapper<T>`,
but the existing tests are extremely non-constexpr-friendly and
so I don't want to get into that rabbit-hole today.

Differential Revision: https://reviews.llvm.org/D93815
2020-12-28 13:24:07 -05:00
Martin Storsjö de698ae734 [libcxx] Convert paths to/from the right narrow code page for narrow strings on windows
On windows, the narrow, char based paths normally don't use utf8, but
can use many different native code pages, and this is what system
functions that operate on files, taking such paths/file names, interpret
them as.

Differential Revision: https://reviews.llvm.org/D91137
2020-12-18 11:24:52 +02:00
Martin Storsjö 48c6500b5b [libcxx] Reorder the two u8path functions, to make the following diff more readable. NFC.
Differential Revision: https://reviews.llvm.org/D91136
2020-12-18 11:24:52 +02:00
Martin Storsjö e83e0cac04 [libcxx] Make filesystem::path::value_type wchar_t on windows
Also set the preferred separator to backslash.

libc++ doesn't compile successfully for windows prior to this change,
and this change on its own isn't enough to make it compile successfully
either, but is the first stepping stone towards making it work correctly.

Most of operations.cpp will need to be touched, both for calling
functions that take wchar paths, but also for using other windows
specific functions instead of the posix functions used so far; that is
handled in later commits.

Changing parts of operations.cpp to generalize the string type handling
in code that doesn't touch system functions.

Differential Revision: https://reviews.llvm.org/D91135
2020-12-18 11:24:52 +02:00
Azat Khuzhin 6340f890bb [libc++] Fix extern C for __sanitizer_annotate_contiguous_container() (for gcc)
gcc supports it only at the beginning:

    $ g++ -o /dev/null -c /tmp/test_extern.cpp
    $ cat /tmp/test_extern.cpp
    extern "C" __attribute__ ((__visibility__("default"))) int foo();

Otherwise:

    $ g++ -o /dev/null -c /tmp/test_extern.cpp
    /tmp/test_extern.cpp:1:52: error: expected unqualified-id before string constant
        1 | __attribute__ ((__visibility__("default"))) extern "C" int foo();
          |                                                    ^~~
    $ cat /tmp/test_extern.cpp
    __attribute__ ((__visibility__("default"))) extern "C" int foo();

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D93316
2020-12-17 16:20:24 -05:00
Martin Storsjö 08a00c6f43 [libcxx] Remove ifdefs in the message to static_assert. NFC.
Differential Revision: https://reviews.llvm.org/D93283
2020-12-17 13:37:52 +02:00
Louis Dionne a00290ed10 [libc++] Fix allocate_shared when used with an explicitly convertible allocator
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.
2020-12-15 11:50:06 -05:00
Louis Dionne b3d1d1f4ff [libc++] Remove unnecessary static assertion in allocate_shared
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
2020-12-14 17:47:43 -05:00
Louis Dionne 3b7280f5e4 [libc++] NFCI: Return pointer instead of reference from __shared_ptr_emplace helper method
This makes __get_alloc consistent with __get_elem, and will reduce the
diff required to implement P0674R1.
2020-12-14 17:46:09 -05:00
Louis Dionne 19d57b5c42 [libc++] Refactor allocate_shared to use an allocation guard
This commit is a step towards making it easier to add support for arrays
in allocate_shared. Adding support for arrays will require writing multiple
functions, and the current complexity of writing allocate_shared is
prohibitive for understanding.

Differential Revision: https://reviews.llvm.org/D93130
2020-12-14 17:10:05 -05:00
Louis Dionne 7ad49aec12 [libc++] Split allocator_traits and pointer_traits out of <memory>
In addition to making the code a lot easier to grasp by localizing many
helper functions to the only file where they are actually needed, this
will allow creating helper functions that depend on allocator_traits
outside of <memory>.

This is done as part of implementing array support in allocate_shared,
which requires non-trivial array initialization algorithms that would be
better to keep out of <memory> for sanity. It's also a first step towards
splitting up our monolithic headers into finer grained ones, which will
make it easier to reuse functionality across the library. For example,
it's just weird that we had to define `addressof` inside <type_traits>
to avoid circular dependencies -- instead it's better to implement those
in true helper headers.

Differential Revision: https://reviews.llvm.org/D93074
2020-12-14 16:13:57 -05:00
Arthur O'Dwyer 3c8e31e17b [libc++] ADL-proof <functional> by adding _VSTD:: qualification on calls.
- 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
2020-12-14 12:08:34 -05:00
Arthur O'Dwyer be4c657b01 [libc++] Consistently replace `::new(__p) T` with `::new ((void*)__p) T`. NFCI.
Everywhere, normalize the whitespace to `::new (EXPR) T`.
Everywhere, normalize the spelling of the cast to `(void*)EXPR`.

Without the cast to `(void*)`, the expression triggers ADL on GCC.
(I think this is a GCC bug: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98249)
Even if it doesn't trigger ADL, it still seems incorrect to use any argument
that's not exactly `(void*)` because that opens the possibility of overload
resolution picking a user-defined overload of `operator new`, which would be
wrong.

Differential Revision: https://reviews.llvm.org/D93153
2020-12-14 12:08:34 -05:00
Arthur O'Dwyer b6f1917415 [libc++] Fix some one-off typos in comments. NFCI. 2020-12-14 09:54:58 -05:00
Arthur O'Dwyer ce9ac549c9 [libc++] Remove __is_construct::__nat. NFCI.
This type has been unused since commit 5b4cc84b87.
2020-12-14 09:54:58 -05:00
Arthur O'Dwyer e9eb99999f [libc++] s/insertible/insertable/g. NFCI. 2020-12-14 09:54:58 -05:00
Arthur O'Dwyer 1d7c39e14e [libc++] s/Birdirectional/Bidirectional/g. NFCI. 2020-12-14 09:54:57 -05:00
Louis Dionne ece3e5bb8b [libc++] NFCI: Implement make_shared as allocate_shared with std::allocator
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
2020-12-11 12:01:48 -05:00
Marek Kurdej da97d12cc0 [libc++] Remove invalid use of `#if _LIBCPP_STD_VER >= 11`, as `_LIBCPP_STD_VER` can never be less than 11.
The relevant part of `__config` is:
```
#ifndef _LIBCPP_STD_VER
#  if  __cplusplus <= 201103L
#    define _LIBCPP_STD_VER 11
```

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D93025
2020-12-11 08:31:59 +01:00
Arthur O'Dwyer 3696227c10 [libc++] ADL-proof by adding _VSTD:: qualifications to memmove etc.
Generally these calls aren't vulnerable to ADL because they involve only
primitive types. The ones in <list> and <vector> drag in namespace std
but that's OK; the ones in <fstream> and <strstream> are vulnerable
iff `CharT` is an enum type, which seems far-fetched.
But absolutely zero of them *need* ADL to happen; so in my opinion
they should all be consistently qualified, just like calls to any
other (non-user-customizable) functions in namespace std.

Also: Include <cstring> and <cwchar> in <__string>.
We seemed to be getting lucky that <memory> included <iterator>
included <iosfwd> included <wchar.h>. That gave us the
global-namespace `wmemmove`, but not `_VSTD::wmemmove`.
This is now fixed.

I didn't touch these headers:
<ext/__hash> uses strlen, safely
<support/ibm/locale_mgmt_aix.h> uses memcpy, safely
<string.h> uses memchr and strchr, safely
<wchar.h> uses wcschr, safely
<__bsd_locale_fallbacks.h> uses wcsnrtombs, safely

Differential Revision: https://reviews.llvm.org/D93061
2020-12-10 22:03:12 -05:00
Arthur O'Dwyer b12ea06521 [libc++] Include C++ headers, not C headers, in <charconv>.
This matches how libc++ does it in all other C++ headers
(that is, headers not ending in ".h").
We need to include <cstring> if we want to use `_VSTD::memmove`
instead of unqualified ADL `memmove`. Even though ADL doesn't
physically matter in <charconv>'s specific case, I'm trying
to migrate libc++ to using `_VSTD::memmove` for all cases
(because some of them do matter, and this way it's easier to
grep for outliers).

Differential Revision: https://reviews.llvm.org/D92875
2020-12-10 22:03:12 -05:00
Louis Dionne 092e8a7ea3 [libc++] NFCI: Refactor __shared_ptr_emplace
This is the first of a series of patches leading up to the implementation
of P0674r1, i.e. array support in allocate_shared. I am splitting this
up into multiple patches because the overall change is very tricky and
I want to isolate potential breakage.
2020-12-10 16:45:58 -05:00
Richard Smith 2a2c228c7a Add new 'preferred_name' attribute.
This attribute permits a typedef to be associated with a class template
specialization as a preferred way of naming that class template
specialization. This permits us to specify that (for example) the
preferred way to express 'std::basic_string<char>' is as 'std::string'.

The attribute is applied to the various class templates in libc++ that have
corresponding well-known typedef names.

This is a re-commit. The previous commit was reverted because it exposed
a pre-existing bug that has since been fixed / worked around; see
PR48434.

Differential Revision: https://reviews.llvm.org/D91311
2020-12-09 12:22:35 -08:00
Arthur O'Dwyer 1968804ac7 [libc++] Add _VSTD:: qualifications to ADL-proof <algorithm>.
Relevant blog post: https://quuxplusone.github.io/blog/2019/09/26/uglification-doesnt-stop-adl/

Differential Revision: https://reviews.llvm.org/D92776
2020-12-08 17:05:38 -05:00
Arthur O'Dwyer 35c3b53943 [libc++] ADL-proof __libcpp_is_nothrow_constructible.
The GCC C++20 buildbot hit this ADL call; Clang doesn't,
presumably because it uses a compiler builtin instead of
this codepath in <type_traits>.
https://buildkite.com/llvm-project/libcxx-ci/builds/674
2020-12-08 17:05:38 -05:00
Louis Dionne a65dc08d10 [libc++] Implement missing feature-test macro __cpp_lib_shared_ptr_arrays
This was forgotten when we implemented support for arrays in std::shared_ptr
in https://reviews.llvm.org/D62259.
2020-12-08 15:46:45 -05:00
Yuriy Chernyshov b526d87618 [libc++] Add std::hash<char8_t> specialization if char8_t is enabled
Differential Revision: https://reviews.llvm.org/D92325
2020-12-08 13:46:18 -05:00
Arthur O'Dwyer c0428b3c0c [libc++] ADL-proof <iterator>. `__convert_to_integral` is not a customization point.
The interesting change here is that we no longer consider `__convert_to_integral`
an ADL customization point for the user's types. I think the new behavior
is defensible. The old behavior had come from D7449, where Marshall explicitly
said "people can't define their own [`__convert_to_integral` overloads]."

Differential Revision: https://reviews.llvm.org/D92814
2020-12-08 11:19:16 -05:00
Richard Smith a1344779ab Revert "Add new 'preferred_name' attribute."
This change exposed a pre-existing issue with deserialization cycles
caused by a combination of attributes and template instantiations
violating the deserialization ordering restrictions; see PR48434 for
details.

A previous commit attempted to work around PR48434, but appears to have
only been a partial fix, and fixing this properly seems non-trivial.
Backing out for now to unblock things.

This reverts commit 98f76adf4e and
commit a64c26a47a.
2020-12-08 00:42:48 -08:00
Richard Smith 98f76adf4e Add new 'preferred_name' attribute.
This attribute permits a typedef to be associated with a class template
specialization as a preferred way of naming that class template
specialization. This permits us to specify that (for example) the
preferred way to express 'std::basic_string<char>' is as 'std::string'.

The attribute is applied to the various class templates in libc++ that have
corresponding well-known typedef names.

Differential Revision: https://reviews.llvm.org/D91311
2020-12-07 12:53:07 -08:00
Marek Kurdej bf8683adfa [libc++] [docs] Mark LWG3055 as complete. Use string_view instead of string in path::operator+=(ECharT).
The issue didn't change the behaviour which is tested in libcxx/test/std/input.output/filesystems/class.path/path.member/path.concat.pass.cpp.

The change to use string_view instead of string is not strictly necessary.

<filesystem> was added in commit 998a5c8831 (Implement <filesystem>).

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D92731
2020-12-07 20:18:09 +01:00
Marek Kurdej e2279c2350 [libc++] [docs] Mark P1865 as complete since 11.0 as it was implemented together with P1135. Fix synopses in <barrier> and <latch>.
It was implemented in commit 54fa9ecd30 ([libc++] Implementation of C++20's P1135R6 for libcxx).
2020-12-06 15:36:52 +01:00
Marek Kurdej f6326736ba [libc++] [LWG3374] Mark `to_address(const Ptr& p)` overload `constexpr`.
Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D92659
2020-12-06 15:26:26 +01:00
Zbigniew Sarbinowski e6c89a499d [SystemZ][ZOS] Fix the usage of pthread_t within libc++
This is the the minimal change introduced in [[ https://reviews.llvm.org/D88599 | D88599 ]]  to unblock the controversial change and discussion of proper separation between thread from thread id which will continue in D88599.

This patch will address the differences of definition of pthread_t on z/OS vs. Linux and other OS. Main trick to make the code work on z/OS relies on redefining libcpp_thread_id type and _LIBCPP_NULL_THREAD macro. This is necessary to separate initialization of libcxx_thread_id from the one of __libcxx_thread_t;

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D91875
2020-12-05 17:46:30 +00:00
Arthur O'Dwyer b8bc4e153f [libc++] Update the commented "synopsis" in <algorithm> to match current reality.
The synopsis now reflects what's implemented. It does NOT reflect
all of what's specified in C++20. The "constexpr in C++20" markings
are still missing from these 12 algorithms, because they are still
unimplemented by libc++:

    reverse partition sort nth_element next_permutation prev_permutation
    push_heap pop_heap make_heap sort_heap partial_sort partial_sort_copy

All of the above algorithms were excluded from [P0202].

All of the above algorithms were made constexpr in [P0879] (along with
swap_ranges, iter_swap, and rotate — we've already implemented those three).

Differential Revision: https://reviews.llvm.org/D92255
2020-12-04 17:53:54 -05:00
Arthur O'Dwyer 14098cf6c0 [libc++] [P0202] constexpr set_union, set_difference, set_symmetric_difference, merge
These had been waiting on the ability to use `std::copy` from
constexpr code (which in turn had been waiting on the ability to
use `is_constant_evaluated()` to switch between `memmove` and non-`memmove`
implementations of `std::copy`). That work landed a while ago,
so these algorithms can all be constexpr in C++20 now.

Simultaneously, update the tests for the set algorithms.

- Use an element type with "equivalent but not identical" values.
- The custom-comparator tests now pass something different from `operator<`.
- Make the constexpr coverage match the non-constexpr coverage.

Differential Revision: https://reviews.llvm.org/D92255
2020-12-04 17:53:54 -05:00
Brett Gutstein 297c839e2d [libc++] fix std::sort(T**, T**)
previously, invocations of std::sort(T**, T**) casted the arguments to
(size_t *). this breaks sorting on systems for which pointers don't fit
in a size_t. change the cast to (uintptr_t *) and add a test.

Differential Revision: https://reviews.llvm.org/D92190
2020-12-04 16:05:21 -05:00
Martin Storsjö 6be11e35d5 [libcxx] Implement c++2a char8_t input/output of std::filesystem::path
This implements the std::filesystem parts of P0482 (which is already
marked as in progress), and applies the actions that are suggested
in P1423.

Differential Revision: https://reviews.llvm.org/D90222
2020-12-04 11:37:05 +02:00
Arthur O'Dwyer d430330788 [libc++] Update and normalize the "all the headers" tests.
Some C++20 headers weren't added properly to all three of these
test files. Add them, and take the time to normalize the formatting
so that

    diff <(grep '#include' foo.cpp) <(grep '#include' bar.cpp)

shows no diffs (except that `no_assert_include` deliberately
excludes `<cassert>`).

- Add macro guards to <{barrier,latch,semaphore}>.
- Add macro guards to <experimental/simd>.
- Remove an include of <cassert> from <semaphore>.
- Instead, include <cassert> in the semaphore tests.

Differential Revision: https://reviews.llvm.org/D92525
2020-12-03 15:01:38 -05:00
zoecarver 644f68ed4d [libc++] Add slice_array operator= valarray overload.
Add the slice_array::operator=(const std::valarray<T>& val_arr) overload.

Fixes https://llvm.org/PR40792.

Differential Revision: https://reviews.llvm.org/D58735
2020-12-02 10:49:20 -08:00
Marek Kurdej a984dcaf7c [libc++] [P0482] [C++20] Implement missing bits for codecvt and codecvt_byname.
Add codecvt*<char16_t, char8_t> and codecvt*<char32_t, char8_t>.
Deprecate codecvt<char(16|32)_t, char>.
Enable disabled tests.
Update _LIBCPP_STD_VER to use 20 for C++20. Add _LIBCPP_DEPRECATED_IN_CXX20 macro.

Reviewed By: ldionne, #libc, #libc_abi

Differential Revision: https://reviews.llvm.org/D91517
2020-12-02 09:01:58 +01:00
Martin Storsjö 0d7bd72f5a [libcxx] Apply msvcrt specific exception for lgamma() to mingw configurations, too
This fixes linking code that uses some bits of the <random> header
on mingw targets.

Differential Revision: https://reviews.llvm.org/D92379
2020-12-02 09:55:16 +02:00
Arthur O'Dwyer e181a6aedd s/instantate/instantiate/ throughout. NFCI.
The static_assert in "libcxx/include/memory" was the main offender here,
but then I figured I might as well `git grep -i instantat` and fix all
the instances I found. One was in user-facing HTML documentation;
the rest were in comments or tests.
2020-12-01 22:13:40 -05:00
Arthur O'Dwyer d586f92c94 [libc++] Consistently replace `std::` qualification with `_VSTD::` or nothing. NFCI.
I used a lot of `git grep` to find places where `std::` was being used
outside of comments and assert-messages. There were three outcomes:

- Qualified function calls, e.g. `std::move` becomes `_VSTD::move`.
    This is the most common case.

- Typenames that don't need qualification, e.g. `std::allocator` becomes `allocator`.
    Leaving these as `_VSTD::allocator` would also be fine, but I decided
    that removing the qualification is more consistent with existing practice.

- Names that specifically need un-versioned `std::` qualification,
    or that I wasn't sure about. For example, I didn't touch any code in
    <atomic>, <math.h>, <new>, or any ext/ or experimental/ headers;
    and I didn't touch any instances of `std::type_info`.

In some deduction guides, we were accidentally using `class Alloc = typename std::allocator<T>`,
despite `std::allocator<T>`'s type-ness not being template-dependent.
Because `std::allocator` is a qualified name, this did parse as we intended;
but what we meant was simply `class Alloc = allocator<T>`.

Differential Revision: https://reviews.llvm.org/D92250
2020-12-01 22:13:39 -05:00
Arthur O'Dwyer 40950a44b9 [libc++] ADL-proof <thread>, and eliminate `using namespace chrono`.
Since we know exactly which identifiers we expect to find in `chrono`,
a using-directive seems like massive overkill. Remove the directives
and qualify the names as needed.

One subtle trick here: In two places I replaced `*__p` with `*__p.get()`.
The former is an unqualified call to `operator*` on a class type, which
triggers ADL and breaks the new test. The latter is a call to the
built-in `operator*` on pointers, which specifically
does NOT trigger ADL thanks to [over.match.oper]/1.

Differential Revision: https://reviews.llvm.org/D92243
2020-12-01 22:13:39 -05:00
Louis Dionne 2671fccf03 [libc++] NFC: Remove unused macros in <__config> 2020-12-01 16:51:25 -05:00
Louis Dionne c30d5101f1 [libc++] Optimize the number of assignments in std::exclusive_scan
Reported in https://twitter.com/blelbach/status/1169807347142676480

Differential Revision: https://reviews.llvm.org/D67273
2020-12-01 12:49:45 -05:00
Zequan Wu 871f96eed3 [libcxx] remove checks for __STDCPP_THREADS__ as it is defined by compiler
Differential Revision: https://reviews.llvm.org/D92349
2020-11-30 16:36:47 -08:00
Harald van Dijk fba0b65f72
[libc++] hash<long double>: adjust for x86-64 ILP32
x86-64 ILP32 mode (x32) uses 32-bit size_t, so share the code with ix86 to zero out padding bits, not with x86-64 LP64 mode.

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D91349
2020-11-29 13:52:28 +00:00
Mark de Wever 67c88e47bd [libc++] P1645 constexpr for <numeric>
Implements P1645: constexpr for <numeric> algorithms

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D90569
2020-11-28 17:02:54 +01:00
Arthur O'Dwyer 03ee461276 [libc++] Consistently unparenthesize `numeric_limits<T>::max`. NFCI.
I think people were sometimes parenthesizing `(foo::max)()` out of
misplaced concern that an unparenthesized `foo::max()` would trip up
Windows' `max(a,b)` macro. However, this is not the case: `max(a,b)`
should be tripped up only by an unparenthesized call to `foo::max(a,b)`,
and in fact we already do `_VSTD::max(a,b)` all over the place anyway
without any guards.

However, in order to do it without guards, we must also
wrap the header in _LIBCPP_PUSH_MACROS, which <span> was not.

Differential Revision: https://reviews.llvm.org/D92240
2020-11-27 17:27:36 -05:00
zoecarver b2943765e7 [libc++] Use std::move in numeric algorithms (P0616R0).
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
2020-11-27 11:09:44 -08:00
Bruce Mitchener 527a7fdfbd [libc++] Replace several uses of 0 by nullptr
Differential Revision: https://reviews.llvm.org/D43159
2020-11-27 10:00:21 -05:00
Marek Kurdej 841132efda [libc++] [P0966] [C++20] Fix bug PR45368 by correctly implementing P0966: string::reserve should not shrink.
This patch fixes the implementation as well as the tests that didn't actually test the wanted behaviour.
You'll find all the details in the bug report.
It adds as well deprecation warning for reserve() (without argument) and adds a test.

http://wg21.link/P0966R1
https://bugs.llvm.org/show_bug.cgi?id=45368
https://reviews.llvm.org/D54992

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D91778
2020-11-26 10:13:12 +01:00
Louis Dionne a78aaa1ad5 [libc++] Factor out common logic for calling aligned allocation
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
2020-11-25 15:44:50 -05:00
Arthur O'Dwyer bbf8a9ca3f [libc++] ADL-proof <variant> by adding _VSTD:: qualification on calls.
Differential Revision: https://reviews.llvm.org/D92036
2020-11-25 09:19:37 -05:00
Mark de Wever ecabb39ca1 Revert "[libc++] P1645 constexpr for <numeric>"
This reverts commit eb9b063539.

The commit fails to build on build bots using LLVM 8.
2020-11-25 13:46:08 +01:00
Mark de Wever eb9b063539 [libc++] P1645 constexpr for <numeric>
Implements P1645: constexpr for <numeric> algorithms

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D90569
2020-11-25 13:19:32 +01:00
Marek Kurdej 9c97e4ef45 [libc++] [P0482] [C++20] Implement missing bits for atomic
Added: ATOMIC_CHAR8_T_LOCK_FREE, atomic<char8_t>, atomic_char8_t.
http://wg21.link/P0482

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D91706
2020-11-24 21:07:57 +01:00
Louis Dionne 0ec73a61cc [libc++] NFC: Fix confusing indentation in <numeric> 2020-11-24 12:30:31 -05:00
Mark de Wever 1a036e9cc8 [libcxx] Implement P1956 rename low-level bit functions
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
2020-11-24 17:37:06 +01:00
Arthur O'Dwyer ee95c7020c [libc++] Remove _LIBCPP_CONSTEXPR_AFTER_CXX17_WITH_IS_CONSTANT_EVALUATED.
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.
2020-11-24 11:04:21 -05:00
zoecarver 0a20660c8f [libcxx] Resolve LWG 2724 protected -> private.
Fixes LWG issue 2724: "The protected virtual member functions of memory_resource should be private."

Differential Revision: https://reviews.llvm.org/D66615
2020-11-23 14:27:22 -08:00
Arthur O'Dwyer 6e965df605 Revert "Revert "[libc++] ADL-proof <vector> by adding _VSTD:: qualification on calls.""
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
2020-11-20 20:59:18 -05:00
Zbigniew Sarbinowski 2c7e24c4b6 Guard init_priority attribute within libc++
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
2020-11-20 15:53:26 -05:00
Mikhail Goncharov 620adacf87 Revert "[libc++] ADL-proof <vector> by adding _VSTD:: qualification on calls."
This reverts commit 40267cc989.

Build fails, e.g. http://lab.llvm.org:8011/#/builders/23/builds/108
2020-11-19 15:36:49 +01:00
Arthur O'Dwyer 40267cc989 [libc++] ADL-proof <vector> by adding _VSTD:: qualification on calls.
(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
2020-11-19 09:19:16 -05:00
Louis Dionne be00e8893f [libc++] Clarify how we pick the typeinfo comparison
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
2020-11-18 16:58:45 -05:00
Xiang Xiao f0785c1f7a [libcxx] Port to NuttX (https://nuttx.apache.org) RTOS
Since NuttX conform to POSIX standard, the code need to add is very simple.

Differential Revision: https://reviews.llvm.org/D88718
2020-11-18 16:20:56 -05:00
Mark de Wever 3abaf6cde7 [libc++] Implements multiline regex support.
This resolves LWG2503.
2020-11-18 18:17:36 +01:00
Martin Storsjö 83a03867da [libcxx] Add missing _LIBCPP_FUNC_VIS on a few win32 locale functions
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
2020-11-18 11:04:55 +02:00
Eric Fiselier 9c09757bca [libc++] Revert switch-based std::variant implementation again.
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
2020-11-17 23:09:31 -05:00
Louis Dionne 48138e7338 [libc++] Do not error out when we don't know the file format
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.
2020-11-17 13:18:51 -05:00
Louis Dionne 121f27f3ac [libc++] Only include_next <wctype.h> if it exists
This allows building on platforms that don't provide that header.
2020-11-17 13:14:36 -05:00
Louis Dionne f1cf6b47e4 [libc++] Remove transitional #error message
It's been more than 4 years now, so anyone that was defining
_LIBCPP_TRIVIAL_PAIR_COPY_CTOR has had ample time to see that
error and fix their code.
2020-11-16 13:36:16 -05:00
Marek Kurdej d2acf22927 [gcc] Fix -Wempty-body warning. NFC. 2020-11-15 16:17:52 +01:00
Zbigniew Sarbinowski 6a8099e0f6 [libc++] Port the time functions to z/OS
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
2020-11-13 10:47:57 -05:00
Zbigniew Sarbinowski aa8a5b800d [SystemZ][ZOS] libcxx - no posix memalign
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
2020-11-12 14:47:58 -05:00
Louis Dionne 997d41cdec [libc++] Instantiate additional <iostream> members in the dylib
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
2020-11-12 13:52:47 -05:00
Louis Dionne 777ca48c9f Revert "[SystemZ][ZOS] Porting the time functions within libc++ to z/OS"
This reverts commit 173b51169b. That commit was applied incorrectly,
and undid previous changes. That was clearly not intended.
2020-11-12 13:36:18 -05:00
Zbigniew Sarbinowski 173b51169b [SystemZ][ZOS] Porting the time functions within libc++ to z/OS
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
2020-11-12 11:29:13 -05:00
Ruslan Arutyunyan e5ec94a1a0 [libc++] Implement P0919R3: heterogenous lookup for unordered containers
Implement heterogenous lookup for unordered containers, including the
refinement from P1690R1.

Differential Revision: https://reviews.llvm.org/D87171
2020-11-11 17:44:42 -05:00
Louis Dionne 69ca17a92c [libc++] NFC: Simplify incude of <cstdlib>
We include <exception>, which includes <cstdlib> unconditionally anyway.
2020-11-11 17:04:32 -05:00
Xiang Xiao 20acf6d588 [libcxx] Check _LIBCPP_PROVIDES_DEFAULT_RUNE_TABLE first in __locale
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
2020-11-11 15:32:59 -05:00
zoecarver 31dfaff3b3 [libc++] Change requirements on linear_congruential_engine.
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
2020-11-10 18:23:22 -08:00
Louis Dionne 02af11094f [libc++] NFC: Add helper methods to simplify __shared_ptr_emplace
The previous implementation was really difficult to follow, especially
with the get() method sharing the same name as std::unique_ptr::get().
2020-11-10 12:49:19 -05:00
Muiez Ahmed e72e785d47 [SystemZ][z/OS] Enable POSIX_l functions for z/OS
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
2020-11-10 09:57:11 -05:00
Louis Dionne bb43a0cd4a [libc++] Add a Buildkite job that tests back-deployment on Apple
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
2020-11-05 18:26:08 -05:00
Louis Dionne 2eadbc8614 [libc++] Rework the whole availability markup implementation
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
2020-11-05 12:28:52 -05:00
Louis Dionne 0df0d0fe2d [libc++] NFC: Remove trailing whitespace 2020-11-04 14:08:06 -05:00
Louis Dionne 6706342f48 [libc++] Remove the ability to not install the support headers
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.
2020-11-04 11:45:34 -05:00
Louis Dionne d9a4f936d0 [libc++] Move <memory> helpers outside of std::allocator_traits
They don't really belong as members of allocator_traits.
2020-11-03 12:27:26 -05:00
Nico Weber 8954fd436c [libcxx] Fix regression where `ninja all` doesn't copy libcxx headers
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.
2020-11-01 21:34:51 -05:00
Michael Park 35d2269111 [libc++] Re-apply the switch-based std::variant implementation
This commit is a mass re-application of the following commits:

  7d15ece79c
  e0ec7a0206
  02197f7e50
  a175a96517

Those were temporarily reverted in 057028ed39, and never re-applied.
Re-committed by @ldionne (author edited for credit).

Differential Revision: https://reviews.llvm.org/D90168
2020-10-28 17:09:11 -04:00
Louis Dionne 91336a0c61 [libc++] Move the #error message for no localization to <locale.h>
<locale.h> is lower level than <__locale>, so that's where we want the
error to live for systems that don't provide localization support.
2020-10-28 09:49:37 -04:00
Martin Storsjö 70bba9ef35 [libcxx] Don't truncate intermediates to wchar_t when widening
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
2020-10-27 23:58:27 +02:00
Louis Dionne 88ffc72717 [libc++] Add a libc++ configuration that does not support localization
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
2020-10-27 14:56:30 -04:00
Martin Storsjö 0be27302d4 [libcxx] Fix typo in spelling of 'sentinel'. NFC.
Differential Revision: https://reviews.llvm.org/D90220
2020-10-27 20:38:32 +02:00
Louis Dionne 48e4b0fd3a [runtimes] Revert the libc++ __config_site change
This is a massive revert of the following commits (from most revent to oldest):

	2b9b7b5775.
	529ac33197
	28270234f1
	69c2087283
	b5aa67446e
	5d796645d6

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.
2020-10-23 09:41:48 -04:00
Louis Dionne ce565861c7 [libc++] Drop old workaround for iostreams instantiations missing from the dylib
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.
2020-10-22 14:51:25 -04:00
Louis Dionne 69c2087283 [libc++] Fix compiler-rt build by copying libc++ headers to <build>/include
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.
2020-10-21 16:56:33 -04:00
Louis Dionne b5aa67446e [libc++] Fix the installation of libc++ headers since the __config_site change 2020-10-21 12:54:42 -04:00
Louis Dionne 5d796645d6 [take 2] [libc++] Include <__config_site> from <__config>
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
2020-10-21 10:40:33 -04:00
Louis Dionne eb60c48744 [libc++] Revert "Include <__config_site> from <__config>"
This temporarily reverts commit 1e46d1aa until I find a solution to fix
the libc++abi and libunwind test suites with that change.
2020-10-21 09:18:29 -04:00
Louis Dionne 1e46d1aa3f [libc++] Include <__config_site> from <__config>
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
2020-10-21 08:46:57 -04:00
Eric Fiselier 229db36474 [libc++] Make __shared_weak_count vtable consistent across all build configurations
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
2020-10-20 08:19:43 -04:00
Louis Dionne ec0dc70efc [libc++] Add more tests for operator<< on std::complex 2020-10-19 13:23:59 -04:00
Louis Dionne 6abc15ae3c [libc++] Reduce dependencies on <iostream> from <random>
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.
2020-10-15 13:40:18 -04:00
Louis Dionne e0d01294bc [libc++] Allow building libc++ on platforms without a random device
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.
2020-10-15 12:20:29 -04:00
Louis Dionne 4abb519619 [libc++] NFCI: Define small methods of basic_stringstream inline
It greatly increases readability because defining the methods out-of-line
involves a ton of boilerplate template declarations.
2020-10-09 14:33:49 -04:00
Louis Dionne c778f6c4f9 [libc++] Clean up logic around aligned/sized allocation and deallocation
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
2020-10-09 12:43:28 -04:00
Louis Dionne 12805513a6 [libc++] Remove some workarounds for C++03
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.
2020-10-09 12:35:13 -04:00
Louis Dionne 8da0df3d6d [libc++] Remove unused includes of Availability.h
Since ebaf1d5e2b, the macros defined in <Availability.h> are not used
anymore.
2020-10-07 18:03:40 -04:00
Louis Dionne 602c193e2a [libc++] Make sure __clear_and_shrink() maintains string invariants
__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
2020-10-07 09:16:59 -04:00
Chris Palmer 9eff07a746 [libc++] Add assert to check bounds in `constexpr string_view::operator[]`
Differential Revision: https://reviews.llvm.org/D88864
2020-10-06 16:57:41 -04:00
Louis Dionne fe7245b772 [libc++] NFC: Rename variant helpers to avoid name clashes
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.
2020-10-05 16:41:25 -04:00
Louis Dionne 04fce1515b [libc++] Fix the build with GCC < 10
For now, we still need to support older GCCs, so work around the lack of
__is_constructible on older GCCs.
2020-10-02 18:01:48 -04:00
Louis Dionne 870827f652 [libc++] NFCI: Remove the _LIBCPP_DEBUG_MODE helper macro
It was used inconsistently and the name was pretty confusing, so we might
as well use `#if _LIBCPP_DEBUG_LEVEL == 2` consistently everywhere.
2020-10-02 15:11:23 -04:00
Louis Dionne 31e820378b [libc++] NFCI: Simplify macro definitions for the debug mode
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.
2020-10-02 15:11:23 -04:00
Louis Dionne 1a92de0064 [libc++] NFCI: Remove _LIBCPP_EXTERN_TEMPLATE2
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.
2020-10-02 14:31:43 -04:00
Petr Hosek 8d26760a95 [CMake] Use -isystem flag to access libc++ headers
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
2020-10-01 12:09:27 -07:00
Richard Smith afcf9c47c5 Fix test failures with trunk clang
- Make the consteval constructor for the zero type be noexcept
- Don't expect three-way comparison of 0 against a comparison category
  to fail
2020-09-29 17:10:07 -07:00
Richard Smith bf434a5f17 Improve the representation of <compare>'s zero-only type.
* 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
2020-09-29 15:44:05 -07:00
Louis Dionne 3e5f9dacb0 [libc++] Fix tests on GCC 10
Also, remove workarounds for ancient Clangs from is_constructible tests.
2020-09-29 12:08:33 -04:00
Louis Dionne d092c91288 [libc++] Fix constexpr dynamic allocation on GCC 10
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.
2020-09-28 17:44:31 -04:00
Louis Dionne 59f8ac3eb4 [libc++] Replace uses of __libcpp_allocate by std::allocator<>
Both are equivalent, however std::allocator can appear in constant
expressions and is higher level.
2020-09-28 16:09:42 -04:00
Louis Dionne c90dee1e90 [libc++] Re-apply fdc41e11f (LWG1203) without breaking the C++11 build
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.
2020-09-23 08:56:00 -04:00
Raphael Isemann e46c1def52 Revert "[libc++] Implement LWG1203"
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.
2020-09-23 10:13:38 +02:00
Louis Dionne 2404ed0202 [libc++] NFC: Collocate C++20 removed members of std::allocator 2020-09-22 17:40:14 -04:00
Louis Dionne fdc41e11f9 [libc++] Implement LWG1203
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
2020-09-22 17:15:31 -04:00
Louis Dionne 0724f8bf47 [libc++] Implement C++20's P0784 (More constexpr containers)
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
2020-09-22 11:20:33 -04:00
Louis Dionne bb09ef9598 [libc++] Fix failures when running the test suite without RTTI 2020-09-21 20:17:24 -04:00
Mark de Wever d4dd961300 Fixes complexity of map insert_or_assign with a hint.
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
2020-09-19 16:28:55 +02:00
Louis Dionne a3c28ccd49 [libc++] Remove some workarounds for missing variadic templates
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.
2020-09-17 11:05:39 -04:00
Louis Dionne d9c9a74d0d [libc++] Add missing friend keyword
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.
2020-09-15 14:21:05 -04:00
Marshall Clow 39c8795141 [libc++] Use allocator_traits to consistently allocate/deallocate/construct/destroy objects in std::any
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
2020-09-15 11:04:59 -04:00