Clang is gaining `auto(x)` support in D113393; sadly there
seems to be no feature-test macro for it. Zhihao is opening
a core issue for that macro.
Use `_LIBCPP_AUTO_CAST` where C++20 specifies we should use `auto(x)`;
stop using `__decay_copy(x)` in those places.
In fact, remove `__decay_copy` entirely. As of C++20, it's purely
a paper specification tool signifying "Return just `x`, but it was
perfect-forwarded, so we understand you're going to have to call
its move-constructor sometimes." I believe there's no reason we'd
ever need to do its operation explicitly in code.
This heisenbugs away a test failure on MinGW; see D112214.
Differential Revision: https://reviews.llvm.org/D115686
Implement P1989R2 which adds a range constructor for `string_view`.
Adjust `operator/=` in `path` to avoid atomic constraints caching issue
getting provoked from this PR.
Add defaulted template argument to `string_view`'s "sufficient
overloads" to avoid mangling issues in `clang-cl` builds. It is a
MSVC mangling bug that this works around.
Differential Revision: https://reviews.llvm.org/D113161
Several of our C++20 and C++2b papers were missing the actual revision
number that was voted in to the Standard. The revision number is quite
important because in a few cases, a paper has a revision *after* the
one that is voted into the Standard, which isn't voted into the Standard.
Hence, if we simply followed the wg21.link blindly and implemented that,
we'd end up implementing the latest revision of the paper, which might
not have been voted.
As a fly-by fix, I found out that P1664 had been withdrawn from the
straw polls and had never been voted into the Standard. This commit
removes that entry from our list.
Differential Revision: https://reviews.llvm.org/D112339
Implement P2401 which adds a `noexcept` specification to
`std::exchange`. Treated as a defect fix which is the motivation for
applying this change to all standards mode rather than just C++23 or
later as the paper suggests.
Reviewed By: Quuxplusone, Mordante, #libc
Differential Revision: https://reviews.llvm.org/D111481
Implement P2251 which requires `span` and `basic_string_view` to be
trivially copyable. They already are - this just adds tests to bind that
behavior.
Reviewed By: ldionne, Quuxplusone, Mordante, #libc
Differential Revision: https://reviews.llvm.org/D111197
Update the status with the approved papers and LWG-issues in the October 2021 plenary.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D111166
Louis Dionne