15 Commits

Author SHA1 Message Date
Corentin Jabot
f72b3e1c07
[Clang] Add detailed notes explaining why is_constructible evaluates to false (Revert 16d5db7) (#151935)
Adds explanation why `is_constructible` evaluates to false.

This reapplies as-is e476f968bc8e438a0435d10934f148de570db8eb.
This was reverted in 16d5db71b3c38f21aa17783a8758f947dca5883f because of
a test failure in libc++.

The test failure in libc++ is interesting in that, in the absence of
nested diagnostics a bunch of diagnostics are emitted as error instead
of notes, which we cannot silence with `-verify-ignore-unexpected`.

The fix here is to prevent the diagnostics to be emitted in the first
place.
However this is clearly not ideal and we should make sure to deploy a
better solution in the clang 22 time frame, in the lines of
https://discourse.llvm.org/t/rfc-add-a-new-text-diagnostics-format-that-supports-nested-diagnostics/87641/12

Fixes #150601

---------

Co-authored-by: Shamshura Egor <164661612+egorshamshura@users.noreply.github.com>
2025-08-05 10:51:26 +02:00
Victor Campos
16d5db71b3 Revert "[libc++][Clang] Added explanation why is_constructible evaluated to false. Updated the diagnostics checks in libc++ tests. (#144220)"
This reverts commit e476f968bc8e438a0435d10934f148de570db8eb.

It has introduced a failure tracked by https://github.com/llvm/llvm-project/issues/150601

One libcxx test fail if libcxx is build with no exceptions and no RTTI:
 - libcxx/utilities/expected/expected.expected/value.observers.verify.cpp
2025-07-30 11:05:23 +01:00
Shamshura Egor
e476f968bc
[libc++][Clang] Added explanation why is_constructible evaluated to false. Updated the diagnostics checks in libc++ tests. (#144220)
Added explanation why a is constructible evaluated to false. Also fixed
problem with ExtractTypeTraitFromExpression. In case std::is_xxx_v<>
with variadic pack it tries to get template argument, but fails in
expression Arg.getAsType() due to Arg.getKind() ==
TemplateArgument::ArgKind::Pack, but not
TemplateArgument::ArgKind::Type.
Reverts #144127
Fixies
https://github.com/llvm/llvm-project/pull/143309#issuecomment-2970012054
2025-07-08 12:58:34 +02:00
Jakub Mazurkiewicz
c8917048e3
[libc++] Implement bind_back (#81055)
Implement `std::bind_back` function from P2387R3 "Pipe support for
user-defined range adaptors".
2024-04-09 11:10:20 -04:00
Louis Dionne
9bb9ec380a
[libc++][NFC] Simplify checks for static assertions in .verify.cpp tests (#67559)
We don't neeed to handle both spellings anymore since we don't support
Clang 15 anymore.
2023-09-28 09:07:08 -04:00
Louis Dionne
72f0edf3f4 [libc++] Remove unnecessary main() function in .compile.pass.cpp and .verify.cpp tests
We pretty consistently don't define those cause they are not needed,
and it removes the potential pitfall to think that these tests are
being run. This doesn't touch .compile.fail.cpp tests since those
should be replaced by .verify.cpp tests anyway, and there would be
a lot to fix up.

As a fly-by, I also fixed a bit of formatting, removed a few unused
includes and made some very minor, clearly NFC refactorings such as
in allocator.traits/allocator.traits.members/allocate.verify.cpp where
the old test basically made no sense the way it was written.

Differential Revision: https://reviews.llvm.org/D146236
2023-03-17 17:56:21 -04:00
Louis Dionne
c2df707666 [libc++] Suppress -Wctad-maybe-unsupported on types w/o deduction guides
There are a handful of standard library types that are intended
to support CTAD but don't need any explicit deduction guides to
do so.

This patch adds a dummy deduction guide to those types to suppress
-Wctad-maybe-unsupported (which gets emitted in user code).

This is a re-application of the original patch by Eric Fiselier in
fcd549a7d828 which had been reverted due to reasons lost at this point.
I also added the macro to a few more types. Reviving this patch was
prompted by the discussion on https://llvm.org/D133425.

Differential Revision: https://reviews.llvm.org/D133535
2022-10-03 14:05:08 -04:00
Muhammad Usman Shahid
76476efd68 Rewording "static_assert" diagnostics
This patch rewords the static assert diagnostic output. Failing a
_Static_assert in C should not report that static_assert failed. This
changes the wording to be more like GCC and uses "static assertion"
when possible instead of hard coding the name. This also changes some
instances of 'static_assert' to instead be based on the token in the
source code.

Differential Revision: https://reviews.llvm.org/D129048
2022-07-25 07:22:54 -04:00
Erich Keane
1da3119025 Revert "Rewording the "static_assert" to static assertion"
Looks like we again are going to have problems with libcxx tests that
are overly specific in their dependency on clang's diagnostics.

This reverts commit 6542cb55a3eb115b1c3592514590a19987ffc498.
2022-07-21 06:40:14 -07:00
Muhammad Usman Shahid
6542cb55a3 Rewording the "static_assert" to static assertion
This patch is basically the rewording of the static assert statement's
output(error) on screen after failing. Failing a _Static_assert in C
should not report that static_assert failed. It’d probably be better to
reword the diagnostic to be more like GCC and say “static assertion”
failed in both C and C++.

consider a c file having code

_Static_assert(0, "oh no!");

In clang the output is like:

<source>:1:1: error: static_assert failed: oh no!
_Static_assert(0, "oh no!");
^              ~
1 error generated.
Compiler returned: 1

Thus here the "static_assert" is not much good, it will be better to
reword it to the "static assertion failed" to more generic. as the gcc
prints as:

<source>:1:1: error: static assertion failed: "oh no!"
    1 | _Static_assert(0, "oh no!");
          | ^~~~~~~~~~~~~~
          Compiler returned: 1

The above can also be seen here. This patch is about rewording
the static_assert to static assertion.

Differential Revision: https://reviews.llvm.org/D129048
2022-07-21 06:34:14 -07:00
Louis Dionne
89a7bdb1f3 [libc++] Add the __bind_back and __compose helpers
Those are going to be used to implement range adaptors,
see D107098 for details.

Differential Revision: https://reviews.llvm.org/D107785
2021-08-11 10:08:20 -04:00
Louis Dionne
ce96d81c47 [libc++][NFC] Simplify tests for bind_front 2021-08-10 11:57:51 -04:00
Louis Dionne
f599e7a789 [libc++] Refactor __perfect_forward, bind_front and not_fn
This patch fixes the constrains on the __perfect_forward constructor
and its call operators, which were incorrect. In particular, it makes
sure that we closely follow [func.require], which basically says that
we must deliver the bound arguments with the appropriate value category
or make the call ill-formed, but not silently fall back to using a
different value category.

As a fly-by, this patch also:
- Adds types __bind_front_t and __not_fn_t to make the result of
  calling bind_front and not_fn more opaque, and improve diagnostics
  for users.
- Adds a bunch of tests for bind_front and remove some that are now
  redundant.
- Adds some missing _LIBCPP_HIDE_FROM_ABI annotations.

Immense thanks to @tcanens for raising awareness about this issue, and
providing help with the = delete bits.

Differential Revision: https://reviews.llvm.org/D107199
2021-08-09 15:32:00 -04:00
Louis Dionne
e35677c07c [libc++] NFC: Remove unused c++98 Lit feature 2021-06-22 16:24:43 -04:00
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