Commit Graph

13 Commits

Author SHA1 Message Date
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 6542cb55a3.
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
Mitch Phillips 041d4012e4 Revert "Rewording "static_assert" diagnostics"
This reverts commit b7e77ff25f.

Reason: Broke sanitizer builds bots + libcxx. 'static assertion
expression is not an integral constant expression'. More details
available in the Phabricator review: https://reviews.llvm.org/D129048
2022-07-14 10:59:20 -07:00
Muhammad Usman Shahid b7e77ff25f 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
2022-07-14 07:47:37 -04:00
Richard Smith 72315d02c4 Treat `std::move`, `forward`, etc. as builtins.
This is extended to all `std::` functions that take a reference to a
value and return a reference (or pointer) to that same value: `move`,
`forward`, `move_if_noexcept`, `as_const`, `addressof`, and the
libstdc++-specific function `__addressof`.

We still require these functions to be declared before they can be used,
but don't instantiate their definitions unless their addresses are
taken. Instead, code generation, constant evaluation, and static
analysis are given direct knowledge of their effect.

This change aims to reduce various costs associated with these functions
-- per-instantiation memory costs, compile time and memory costs due to
creating out-of-line copies and inlining them, code size at -O0, and so
on -- so that they are not substantially more expensive than a cast.
Most of these improvements are very small, but I measured a 3% decrease
in -O0 object file size for a simple C++ source file using the standard
library after this change.

We now automatically infer the `const` and `nothrow` attributes on these
now-builtin functions, in particular meaning that we get a warning for
an unused call to one of these functions.

In C++20 onwards, we disallow taking the addresses of these functions,
per the C++20 "addressable function" rule. In earlier language modes, a
compatibility warning is produced but the address can still be taken.

The same infrastructure is extended to the existing MSVC builtin
`__GetExceptionInfo`, which is now only recognized in namespace `std`
like it always should have been.

This is a re-commit of
  fc30901096,
  a571f82a50,
  64c045e25b, and
  de6ddaeef3,
and reverts aa643f455a.
This change also includes a workaround for users using libc++ 3.1 and
earlier (!!), as apparently happens on AIX, where std::move sometimes
returns by value.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D123345

Revert "Fixup D123950 to address revert of D123345"

This reverts commit aa643f455a.
2022-04-20 17:58:31 -07:00
David Tenty 98d911e01f Revert "Treat `std::move`, `forward`, etc. as builtins."
This reverts commit b27430f9f4 as the
    parent https://reviews.llvm.org/D123345 breaks the AIX CI:

    https://lab.llvm.org/buildbot/#/builders/214/builds/819
2022-04-20 19:14:37 -04:00
David Tenty de6ddaeef3 Revert "Don't treat 'T &forward(T&&)' as builtin."
This reverts commit e43c93dd63 as the
parent https://reviews.llvm.org/D123345 breaks the AIX CI.
2022-04-20 19:14:36 -04:00
Richard Smith e43c93dd63 Don't treat 'T &forward(T&&)' as builtin.
This allows the standard library to diagnose it properly. Suppress
warning in libc++ testsuite for unused result of call to std::forward.
2022-04-18 11:11:21 -07:00
Richard Smith b27430f9f4 Treat `std::move`, `forward`, etc. as builtins.
This is extended to all `std::` functions that take a reference to a
value and return a reference (or pointer) to that same value: `move`,
`forward`, `move_if_noexcept`, `as_const`, `addressof`, and the
libstdc++-specific function `__addressof`.

We still require these functions to be declared before they can be used,
but don't instantiate their definitions unless their addresses are
taken. Instead, code generation, constant evaluation, and static
analysis are given direct knowledge of their effect.

This change aims to reduce various costs associated with these functions
-- per-instantiation memory costs, compile time and memory costs due to
creating out-of-line copies and inlining them, code size at -O0, and so
on -- so that they are not substantially more expensive than a cast.
Most of these improvements are very small, but I measured a 3% decrease
in -O0 object file size for a simple C++ source file using the standard
library after this change.

We now automatically infer the `const` and `nothrow` attributes on these
now-builtin functions, in particular meaning that we get a warning for
an unused call to one of these functions.

In C++20 onwards, we disallow taking the addresses of these functions,
per the C++20 "addressable function" rule. In earlier language modes, a
compatibility warning is produced but the address can still be taken.

The same infrastructure is extended to the existing MSVC builtin
`__GetExceptionInfo`, which is now only recognized in namespace `std`
like it always should have been.

This is a re-commit of
  fc30901096,
  a571f82a50, and
  64c045e25b
which were reverted in
  e75d8b7037
due to a crasher bug where CodeGen would emit a builtin glvalue as an
rvalue if it constant-folds.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D123345
2022-04-17 13:26:16 -07:00
Vitaly Buka e75d8b7037 Revert "Treat `std::move`, `forward`, and `move_if_noexcept` as builtins."
Revert "Extend support for std::move etc to also cover std::as_const and"
Revert "Update test to handle opaque pointers flag flip."

It crashes on libcxx tests https://lab.llvm.org/buildbot/#/builders/85/builds/8174

This reverts commit fc30901096.
This reverts commit a571f82a50.
This reverts commit 64c045e25b.
2022-04-16 00:27:51 -07:00
Richard Smith fc30901096 Extend support for std::move etc to also cover std::as_const and
std::addressof, plus the libstdc++-specific std::__addressof.

This brings us to parity with the corresponding GCC behavior.

Remove STDBUILTIN macro that ended up not being used.
2022-04-15 16:31:39 -07:00
Richard Smith 64c045e25b Treat `std::move`, `forward`, and `move_if_noexcept` as builtins.
We still require these functions to be declared before they can be used,
but don't instantiate their definitions unless their addresses are
taken. Instead, code generation, constant evaluation, and static
analysis are given direct knowledge of their effect.

This change aims to reduce various costs associated with these functions
-- per-instantiation memory costs, compile time and memory costs due to
creating out-of-line copies and inlining them, code size at -O0, and so
on -- so that they are not substantially more expensive than a cast.
Most of these improvements are very small, but I measured a 3% decrease
in -O0 object file size for a simple C++ source file using the standard
library after this change.

We now automatically infer the `const` and `nothrow` attributes on these
now-builtin functions, in particular meaning that we get a warning for
an unused call to one of these functions.

In C++20 onwards, we disallow taking the addresses of these functions,
per the C++20 "addressable function" rule. In earlier language modes, a
compatibility warning is produced but the address can still be taken.

The same infrastructure is extended to the existing MSVC builtin
`__GetExceptionInfo`, which is now only recognized in namespace `std`
like it always should have been.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D123345
2022-04-15 14:09:45 -07:00