Commit Graph

394 Commits

Author SHA1 Message Date
Arthur O'Dwyer dc066888bd [libc++] [P0619] Add _LIBCPP_ABI_NO_BINDER_BASES and remove binder typedefs in C++20.
Differential Revision: https://reviews.llvm.org/D103753
2021-06-15 15:05:44 -04:00
Louis Dionne d9d20802d0 [libc++] Clean up scripts to setup CI on macOS 2021-06-14 15:55:36 -04:00
Christopher Di Bella 462f8f0611 [libcxx][ranges] removes default_initializable from weakly_incrementable and view
also:

* removes default constructors from predefined iterators
* makes span and string_view views

Partially implements P2325.
Partially resolves LWG3326.

Differential Revision: https://reviews.llvm.org/D102468
2021-06-10 22:45:36 +00:00
Louis Dionne a0ae3b0789 [libc++abi] Remove the LIBCXXABI_ENABLE_PIC option
Instead, people should be using CMAKE_POSITION_INDEPENDENT_CODE to control
whether they want to use PIC or not. We should try to avoid reinventing
the wheel whenever CMake natively supports something.

This makes libc++abi consistent with libc++ and libunwind.

Differential Revision: https://reviews.llvm.org/D103973
2021-06-10 12:26:31 -04:00
Christopher Di Bella 546449938a [libcxx][optional] adds missing constexpr operations
Makes the following operations constexpr:
  * `std::swap(optional, optional)`
  * `optional(optional<U> const&)`
  * `optional(optional<U>&&)`
  * `~optional()`
  * `operator=(nullopt_t)`
  * `operator=(U&&)`
  * `operator=(optional<U> const&)`
  * `operator=(optional<U>&&)`
  * `emplace(Args&&...)`
  * `emplace(initializer_list<U>, Args&&...)`
  * `swap(optional&)`
  * `reset()`

P2231 has been accepted by plenary, with the committee recommending
implementers retroactively apply to C++20. It's necessary for us to
implement _`semiregular-box`_ and _`non-propagating-cache`_, both of
which are required for ranges (otherwise we'll need to reimplement
`std::optional` with these members `constexpr`ified).

Differential Revision: https://reviews.llvm.org/D102119
2021-06-10 05:52:47 +00:00
Mark de Wever e7c621a607 [libc++][nfc] Test std::unique_ptr self move assignment.
The post-conditions for the self move assignment of `std::unique_ptr`
were changed. This requires no implementation changes. A test was added
to validate the new post-conditions.

Addresses
- LWG-3455: Incorrect Postconditions on `unique_ptr` move assignment

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D103764
2021-06-09 20:43:12 +02:00
Louis Dionne 12933ba9ea [libc++] NFC: Rewrite the documentation for the debug mode 2021-06-08 16:50:12 -04:00
Louis Dionne 491d045957 [libc++] Remove the old HTML documentation
This commit finishes moving the <atomic> design documents to the RST
documentation and removes the old documentation. https://libcxx.llvm.org
is already pointing to the new documentation only now, so the removal of
the old documentation is really a NFC.

I went over the old documentation and I don't think we're leaving anything
important behind - I think everything important was mentionned in the RST
documentation anyway.
2021-06-08 11:18:12 -04:00
Mark de Wever fbe4c839e8 [libc++][doc] Update Format status.
The first part of the <format> header patch series is now complete for
review. This updates the status document.
2021-06-05 13:58:38 +02:00
zoecarver d31a2e7554 [libcxx][ranges] Add `ranges::empty_view`.
Differential Revision: https://reviews.llvm.org/D103208
2021-06-04 09:38:49 -07:00
Louis Dionne e4d3a993c2 [libc++] Implement LWG3435 (constraints on reverse_iterator and move_iterator) 2021-06-03 15:49:41 -04:00
zoecarver 065cf3f9d7 [libcxx][ranges] Add `default_sentinel` and `default_sentinel_t`.
Refs https://eel.is/c++draft/default.sentinel and https://eel.is/c++draft/iterator.synopsis

Differential Revision: https://reviews.llvm.org/D103487
2021-06-01 14:03:54 -07:00
zoecarver 5671ff20d9 [libcxx] Implement view.interface.
This will unblock work on ranges::view. Based on D101396.

Refs http://eel.is/c++draft/view.interface.

Differential Revision: https://reviews.llvm.org/D101737
2021-06-01 12:34:47 -07:00
zoecarver 367cb9fbd6 [libcxx][docs] Take mutex for common_iterator, common_view, and empty_view. 2021-05-26 13:29:16 -07:00
Arthur O'Dwyer d42d9e10b6 [libc++] [P0619] Hide not1 and not2 under _LIBCPP_ENABLE_CXX20_REMOVED_NEGATORS.
This also provides some of the scaffolding needed by D102992 and D101729, and mops up after D101730 etc.

Differential Revision: https://reviews.llvm.org/D103055
2021-05-25 16:57:16 -04:00
Mark de Wever 7b2606b0b6 [libc++][doc] Update format paper status.
- Fixes paper number P1862 -> P1868. (The title was correct.)
- Marks P1868 as in progress.
- Marks P1892 as in progress.
- Marks LWG-3327 as nothing to do, since the wording change doesn't
  impact the code. (Also updated on the general C++20 status page.)
2021-05-24 16:48:44 +02:00
Louis Dionne 5c26f895b6 [libc++] Fix documentation build failure 2021-05-20 11:01:10 -04:00
Christopher Di Bella d8fad66149 [libcxx][ranges] adds concept `sized_range` and cleans up `ranges::size`
* adds `sized_range` and conformance tests
* moves `disable_sized_range` into namespace `std::ranges`
* removes explicit type parameter

Implements part of P0896 'The One Ranges Proposal'.

Differential Revision: https://reviews.llvm.org/D102434
2021-05-19 18:16:45 +00:00
Christopher Di Bella 0f80365722 [libcxx][iterator][nfc] acquires lock for working on [range.iter.ops]
Differential Revision: https://reviews.llvm.org/D101845
2021-05-19 18:05:33 +00:00
zoecarver fe319a8848 [libcxx][docs] Add two locks: transform_view and take_view.
Assign myself both of these views.
2021-05-13 11:49:20 -07:00
zoecarver 3ac9ff5577 [libcxx][docs] Update the One Ranges PRoposal Status with open revisions.
1. Moves the names into the names column.
2. Changes the names to reflect who's actually working on what.
3. Adds open revisions.
2021-05-13 11:49:20 -07:00
Mark de Wever 6ae15756a5 [libc++][doc] Update the Format library status.
- Move LWG-3218 to the chrono section.
- Mark the several parts 'In progress'.
2021-05-09 17:55:50 +02:00
Louis Dionne 74d096e558 [libc++] Move handling of the target triple to the DSL
This fixes a long standing issue where the triple is not always set
consistently in all configurations. This change also moves the
back-deployment Lit features to using the proper target triple
instead of using something ad-hoc.

This will be necessary for using from scratch Lit configuration files
in both normal testing and back-deployment testing.

Differential Revision: https://reviews.llvm.org/D102012
2021-05-08 11:10:53 -04:00
Arthur O'Dwyer 165ad89947 [libc++] [LIBCXX-DEBUG-FIXME] Our `__debug_less` breaks some complexity guarantees.
`__debug_less` ends up running the comparator up-to-twice per comparison,
because whenever `(x < y)` it goes on to verify that `!(y < x)`.
This breaks the strict "Complexity" guarantees of algorithms like
`inplace_merge`, which we test in the test suite. So, just skip the
complexity assertions in debug mode.

Differential Revision: https://reviews.llvm.org/D101677
2021-05-05 16:21:09 -04:00
Martin Storsjö e87fb6d387 [libcxx] Update docs regarding the need for bash/posix tools for tests on Windows. NFC.
After 39bbfb7726, bash is no longer
a hard requirement.

Differential Revision: https://reviews.llvm.org/D101779
2021-05-04 22:13:08 +03:00
Louis Dionne 6da1c46227 [libc++] NFC: Fix typo in Ranges Status 2021-05-04 13:06:58 -04:00
Louis Dionne 2021d272ad [libc++] Implement ranges::view
Differential Revision: https://reviews.llvm.org/D101547
2021-05-04 11:05:58 -04:00
Louis Dionne 49e7be2e5b [libc++] Disentangle std::pointer_safety
This patch gets rid of technical debt around std::pointer_safety which,
I claim, is entirely unnecessary. I don't think anybody has used
std::pointer_safety in actual code because we do not implement the
underlying garbage collection support. In fact, P2186 even proposes
removing these facilities entirely from a future C++ version. As such,
I think it's entirely fine to get rid of complex workarounds whose goals
were to avoid breaking the ABI back in 2017.

I'm putting this up both to get reviews and to discuss this proposal for
a breaking change. I think we should be comfortable with making these
tiny breaks if we are confident they won't hurt anyone, which I'm fairly
confident is the case here.

Differential Revision: https://reviews.llvm.org/D100410
2021-05-03 14:33:49 -04:00
Marek Kurdej 40f783434b [docs] Automatically update copyright year in libc++. 2021-05-03 18:46:13 +02:00
Marek Kurdej 9d669e859b [docs] Bump the trunk major version to 13 and update copyright year. 2021-05-03 18:44:47 +02:00
Louis Dionne df280d1368 [libc++] Acquire locks on Ranges work
This commit acquires locks on a few elements of Ranges to make sure we don't
duplicate work.

Differential Revision: https://reviews.llvm.org/D101668
2021-05-03 10:39:53 -04:00
Mark de Wever 9f99a9faa3 [libc++][doc] Update the Format library status.
- Use the proper review for 'Fix integral conformance'.
- Mark 'Fix integral conformance' as completed.
- Move some tasks to in progress.
2021-05-02 13:13:55 +02:00
Mark de Wever ca177dcda3 [libc++][doc] Adds a Format library status page.
A status page for libc++'s Format library. The page is inspired by
@zoecarver's Ranges status page.

Differential Revision: https://reviews.llvm.org/D101085
2021-04-24 16:38:18 +02:00
Louis Dionne a3ab5120fd [libc++] Rewrite the tuple constructors to be strictly Standards conforming
This nasty patch rewrites the tuple constructors to match those defined
by the Standard. We were previously providing several extensions in those
constructors - those extensions are removed by this patch.

The issue with those extensions is that we've had numerous bugs filed
against us over the years for problems essentially caused by them. As a
result, people are unable to use tuple in ways that are blessed by the
Standard, all that for the perceived benefit of providing them extensions
that they never asked for.

Since this is an API break, I communicated it in the release notes.
I do not foresee major issues with this break because I don't think the
extensions are too widely relied upon, but we can ship it and see if we
get complaints before the next LLVM release - that will give us some
amount of information regarding how much use these extensions have.

Differential Revision: https://reviews.llvm.org/D96523
2021-04-23 12:46:37 -04:00
Mark de Wever f2ff3b91ec [libc++][doc] Improve Phabricator links.
Removes the "reviews." part of the links as suggested by @ldionne in
D100707.
2021-04-21 20:12:03 +02:00
Christopher Di Bella 9816d43cff [libcxx] adds `iter_difference_t` and `iter_value_t`
Implements parts of:
    * P0896R4 The One Ranges Proposal

Depends on D99855.

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D99863
2021-04-20 19:02:07 +00:00
Mark de Wever 0c8fab9af7 [libcxx][doc] Use Phabricator links.
Use a link to the Phabricator review in the patch column.

Reviewed By: zoecarver, cjdb, #libc

Differential Revision: https://reviews.llvm.org/D100707
2021-04-20 18:41:04 +02:00
Kamlesh Kumar 36c3918ec5 [libc++] [C++20] [P0586] Implement safe integral comparisons
* https://wg21.link/P0586

Reviewed By: #libc, curdeius, Quuxplusone

Differential Revision: https://reviews.llvm.org/D94511
2021-04-20 04:52:59 +05:30
zoecarver 2218f5998b [libc++][gardening] Replace instances of `\x{AD}`.
This is a NFC.

Differential Revision: https://reviews.llvm.org/D100799
2021-04-19 14:59:46 -07:00
Mark de Wever 01ace074fc [libc++] Implements ranges::enable_borrowed_range
This is the initial patch to implement ranges in libc++.

Implements parts of:
- P0896R4 One Ranges Proposal
- P1870 forwarding-range is too subtle
- LWG3379 in several library names is misleading

Reviewed By: ldionne, #libc, cjdb, zoecarver, Quuxplusone

Differential Revision: https://reviews.llvm.org/D90999
2021-04-18 13:35:08 +02:00
Jennifer Chukwu 21bef4e11e [NFC] Fixed Typos
Reviewed By: xgupta

Differential Revision: https://reviews.llvm.org/D100705
2021-04-17 22:02:23 +05:30
Mark de Wever f8f60297d7 [libcxx][doc] Fixes typos. 2021-04-17 18:01:32 +02:00
Louis Dionne 1f8a6dcf12 [libc++] Fix LWG 2874: Constructor shared_ptr::shared_ptr(Y*) should be constrained.
This patch fixes LWG2874. It is based on the original patch by Zoe Carver
originally uploaded at D81417.

Differential Revision: https://reviews.llvm.org/D81417
2021-04-16 09:54:20 -04:00
Christopher Di Bella f280505aa0 [libcxx] adds `std::indirectly_readable_traits` to <iterator>
Implements parts of:
    * P0896R4 The One Ranges Proposal
    * LWG3446 `indirectly_readable_traits` ambiguity for types with both `value_type` and `element_type`

Depends on D99141.

Differential Revision: https://reviews.llvm.org/D99461
2021-04-15 23:59:02 +00:00
zoecarver b12f3ce47f [libcxx][nfc] Assign [ranges.primitives] in "RangesStatus." 2021-04-14 16:09:45 -07:00
Mark de Wever b15c54ad68 [NFC][libc++] Fixes a documentation typo. 2021-04-14 19:33:03 +02:00
Zoe Carver 0f0149b8d3 [libc++][docs] Add status docs for ranges.
The added documents have two tables: 1 containing links to issues and papers related to ranges. And the other contains most of the sections from the One Ranges Proposal, with their dependencies linked. This will allow us to assign work that can be done in parallel.

Differential Revision: https://reviews.llvm.org/D100393
2021-04-13 17:59:42 -07:00
Marek Kurdej 3fca07d7b9 [libc++] [P0458] Add map::contains and set::contains for heterogenous lookup missed in a17b1aed.
Commit rGa17b1aed added `bool contains(const key_type& x) const;` methods to associative containers, but didn't add `template<class K> bool contains(const K& x) const;` for heterogenous lookup.

Reviewed By: #libc, Quuxplusone, ldionne

Differential Revision: https://reviews.llvm.org/D100369
2021-04-13 17:15:58 +02:00
Christopher Di Bella fe31f11cc8 [libcxx] adds `std::incrementable_traits` to <iterator>
Implements parts of:
    - P0896R4 The One Ranges Proposal

Depends on D99041

Differential Revision: https://reviews.llvm.org/D99141
2021-04-13 05:01:45 +00:00
Arthur O'Dwyer 4b7bad9eae [libc++] Implement D2351R0 "Mark all library static cast wrappers as [[nodiscard]]"
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
2021-04-12 12:29:15 -04:00
Louis Dionne 8508b1c133 [libc++] Divorce the std Lit feature from the -std=XXX compiler flag
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
2021-04-12 11:55:39 -04:00
Mark de Wever 48fa06f70b [libc++] Update contributor documentation.
The document has the following updates:
- Rename 'feature test' to 'feature-test', the latter is the spelling
  used in the Standard.
- Add information how an ABI list can be downloaded from Buildkite.

Differential Revision: https://reviews.llvm.org/D99290
2021-04-07 18:33:27 +02:00
Christopher Di Bella 920c0f7e09 [libcxx] adds __cpp_lib_concepts feature-test macro
Also adjusts C++20 status paper to indicate full concepts support.

Depends on D96477, D99817.

Differential Revision: https://reviews.llvm.org/D99805
2021-04-07 16:14:45 +00:00
Christopher Di Bella cedd07df51 [libcxx] fixes `common_reference` requirement for `swappable_with`
LWG3175 identifies that the `common_reference` requirement for
`swappable_with` is over-constraining and doesn't need to concern itself
with cv- or reference qualifiers.

Differential Revision: https://reviews.llvm.org/D99817
2021-04-07 05:51:36 +00:00
Arthur O'Dwyer 2d0f1fa472 [libc++] Header inclusion tests.
As mandated by the Standard's various synopses, e.g. [iterator.synopsis].
Searching the TeX source for '#include' is a good way to find all of these
mandates.

The new tests are all autogenerated by utils/generate_header_inclusion_tests.py.
I was SHOCKED by how many mandates there are, and how many of them
libc++ wasn't conforming with.

Differential Revision: https://reviews.llvm.org/D99309
2021-04-06 15:31:56 -04:00
Christopher Di Bella 96dbdd753a [libcxx] adds remaining callable concepts
* `std::predicate`
* `std::relation`
* `std::equivalence_relation`
* `std::strict_weak_order`

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/D96477
2021-04-06 16:35:57 +00:00
Petr Hosek 96d8c6b571 [CMake] Remove {LIBCXX,LIBCXXABI,LIBUNWIND}_INSTALL_PREFIX
These variables were introduced during early work on the runtimes build
but were obsoleted by {LIBCXX,LIBCXXABI,LIBUNWIND}_INSTALL_LIBRARY_DIR.

Differential Revision: https://reviews.llvm.org/D99697
2021-04-01 10:13:07 -07:00
Louis Dionne c06a8f9caa [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/D97572
2021-03-30 14:06:11 -07:00
Marek Kurdej 0324b46cd8 [libc++] [C++2b] [P2162] Allow inheritance from std::variant.
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
2021-03-25 18:20:50 +01:00
Arthur O'Dwyer 06e2b737aa [libc++] [P1032] Misc constexpr bits in <iterator>, <string_view>, <tuple>, <utility>.
This completes the implementation of P1032's changes to <iterator>,
<string_view>, <tuple>, and <utility> in C++20.
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1032r1.html

Drive-by fix a couple of unintended rvalues in "*iterators*/*.fail.cpp".

Differential Revision: https://reviews.llvm.org/D96385
2021-03-25 10:34:35 -04:00
Martin Storsjö 6718ce4037 [libcxx] [docs] Fix formatting of inline verbatim snippets in the Windows section
Use double backticks instead of single, as single backticks produces
italic formatting.
2021-03-17 11:41:45 +02:00
Martin Storsjö 995a128f07 [libcxx] [docs] Update docs about how to build for Windows
Refresh the existing paragraphs on building in MSVC configurations,
add a sample of one working configuration for MinGW, and add more
details on what's necessary to run the tests these days.

Differential Revision: https://reviews.llvm.org/D97166
2021-03-15 17:30:26 +02:00
Marek Kurdej e9ba25b59d [libc++] [docs] Add link to clang status page for C++2b and fix anchor for C++20. 2021-03-11 20:49:14 +01:00
Marek Kurdej 43e4214173 [libc++] [C++2b] [P1682] Add to_underlying.
* https://wg21.link/P1682

Reviewed By: ldionne, Mordante, #libc

Differential Revision: https://reviews.llvm.org/D97365
2021-03-05 10:31:21 +01:00
zoecarver 84a50f5911 [libc++] Add bind_front function (P0356R5).
Implementes [[ http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0356r5.html | P0356R5 ]]. Adds `bind_front` to `functional`.

Reviewed By: ldionne, #libc, Quuxplusone

Differential Revision: https://reviews.llvm.org/D60368
2021-03-02 16:18:06 -08:00
Marek Kurdej 11ef785cdd [libc++] [docs] [C++2b] Update status page with issues (and forgotten papers) adopted in November 2020 and February 2021 virtual meetings.
Sources:
* https://github.com/cplusplus/draft/pull/4380 (November 2020)
* https://github.com/cplusplus/draft/pull/4523 (February 2021)
* https://github.com/cplusplus/draft/issues?q=is%3Aissue+LWG+Motion
2021-03-01 11:19:18 +01:00
Marek Kurdej 77bd454da3 [libc++] [docs] [C++2b] Update status page with papers adopted in February 2021 virtual meeting. 2021-02-24 09:40:33 +01:00
zoecarver 82c4701d4e [libc++][nfc] SFINAE on pair/tuple assignment operators: LWG 2729.
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
2021-02-19 13:25:34 -08:00
zoecarver dbc89028d7 [libcxx] Fix LWG 2875: shared_ptr::shared_ptr(Y*, D, […]) constructors should be constrained.
Fixes LWG issue 2875.

Differential Revision: https://reviews.llvm.org/D81414
2021-02-19 11:11:39 -08:00
zoecarver 6a328c66d3 [libc++] shared_ptr deleter requirements (LWG 2802).
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
2021-02-18 21:31:07 -08:00
zoecarver 82b82b9430 Mark 2534 as Complete.
c90dee1 fixed LWG 1203 which supresses LWG 2534 as well.

Refs D62889.

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D96885
2021-02-18 21:28:49 -08:00
Nico Weber 9d36f70ef2 libcxx: fix a documentation typo
See `grep 'option.LIBCXX_INCLUDE_TESTS' libcxx/CMakeLists.txt`.
2021-02-18 11:59:51 -05:00
Louis Dionne 5d0d465ad4 [libc++] Mark __cpp_lib_constexpr_memory as being implemented 2021-02-15 15:26:53 -05:00
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
Mark de Wever 171956aab3 Revert "[libc++] Require C++20 to build the benchmarks."
There are build bots without C++20 support building the benchmarks.

This reverts commit 34acc91642.
2021-02-09 19:59:34 +01:00
Mark de Wever 34acc91642 [libc++] Require C++20 to build the benchmarks.
Some work-in-progress patches for the format header contain benchmarks.
The format header requires C++20 to build. This is a preparation to make
it easy to add these benchmarks.

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D96057
2021-02-09 18:34:07 +01:00
zoecarver fab194898b [lic++][docs] Explain noexcept policy for narrow contracts.
Adds documentation around libc++'s policy to add noexcept to things that cannot throw but aren't marked as noexcept.

Refs LWG 3518 and D95251.

Differential Revision: https://reviews.llvm.org/D95821
2021-02-05 11:27:19 -08:00
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
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
xgupta 94fac81fcc [Branch-Rename] Fix some links
According to the [[ https://foundation.llvm.org/docs/branch-rename/ | status of branch rename ]], the master branch of the LLVM repository is removed on 28 Jan 2021.

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D95766
2021-02-01 16:43:21 +05:30
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
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 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
Mark de Wever 193cda105d [libc++][doc] Update the release notes.
Updates the libc++ release notes with the changes since the last
release.

Differential Revision: https://reviews.llvm.org/D95248
2021-01-25 18:32:13 +01:00
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
Mark de Wever 3317b38ef8 [NFC][libc++] Update the implementation status.
During the review of https://reviews.llvm.org/D93912 we failed to notice
the implementation status wasn't updated. This rectifies the issue.
2021-01-22 20:24:33 +01:00
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
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 01a13f127a [libc++] Rename check-cxx-deps to cxx-test-depends for consistency
Several subprojects have targets that do the same thing, and they all
follow the same naming convention: llvm-test-depends, clang-test-depends,
lld-test-depends, etc.

This makes libc++ consistent with other LLVM projects.
Thanks to Duncan Exon Smith for noticing and suggesting the change.

Differential Revision: https://reviews.llvm.org/D94499
2021-01-18 14:41:53 -05:00
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
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
Louis Dionne d86e16e4bd [libc++] NFC: Document the Differential queries to avoid duplicating work
Differential Revision: https://reviews.llvm.org/D94343
2021-01-08 17:47:39 -05:00
Arthur O'Dwyer cdd7cbf7b5 [libc++] Mark [P0809] "LWG2831: Comparing Unordered Containers" as Nothing To Do.
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0809r0.pdf

This issue/paper simply removed some library UB because vendors were
already doing the right thing. libc++ has always done the right thing
(in this respect).

Differential Revision: https://reviews.llvm.org/D93816
2021-01-08 17:33:22 -05:00
Arthur O'Dwyer 963b771e24 [libc++] Mark [P0475] "LWG2511: guaranteed copy elision for piecewise construction" as Complete.
The point of LWG2511 is basically just to make sure that we use
`tuple<Args&&...>` instead of `tuple<Args...>` in a couple of places
inside `scoped_allocator_adaptor` and inside `pair`.
As far as I can tell, this has been true for libc++
since EricWF's D27612 (and maybe even earlier than that).
2021-01-08 17:33:13 -05:00
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
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
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
Marek Kurdej 3f0b637d6b [libc++] [docs] Mark contract-related papers as removed from C++20. 2020-12-30 14:24:26 +01:00