llvm-project

History

[libc++] restrict the expected conversion constructor not compete against copy constructor (#96101 )

fixes #92676

So right now clang does not like 
```
std::expected<std::any, int> e1;
auto e2 = e1;

```

So basically when clang tries to do overload resolution of `auto e2 =
e1;`

It finds

```
expected(const expected&);  // 1. This is OK
expected(const expected<_Up, _OtherErr>&)  requires __can_convert; // 2. This needs to check its constraints
```

Then in `__can_convert`, one of the check is 

```
_Not<is_constructible<_Tp, expected<_Up, _OtherErr>&>>
```
which is checking 
```
is_constructible<std::any, expected<_Up, _OtherErr>&>
```

Then it looks at `std::any`'s constructor
```
  template < class _ValueType,
             class _Tp = decay_t<_ValueType>,
             class     = enable_if_t< !is_same<_Tp, any>::value && !__is_inplace_type<_ValueType>::value &&
                                      is_copy_constructible<_Tp>::value> >
  any(_ValueType&& __value);
```
In the above, `is_copy_constructible<_Tp>` expands to
```
is_copy_constructible<std::expected<std::any, int>>
```

And the above goes back to the original thing we asked : copy the
`std::expected`, which goes to the overload resolution again.

```
expected(const expected&);
expected(const expected<_Up, _OtherErr>&)  requires __can_convert;
```

So the second overload results in a logical cycle. 

I am not a language lawyer. We could argue that clang should give up on
the second overload which has logical cycle, as the first overload is a
perfect match.

Anyway, the fix in this patch tries to short-circuiting the second
overload's constraint check: that is, if the argument matches exact same
`expected<T, E>`, we give up immediately and let the copy constructor to
deal with it

2024-06-26 12:10:59 +01:00

__algorithm

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

__atomic

[libc++] Get the GCC build mostly clean of warnings (#96604 )

2024-06-25 17:31:41 +02:00

__bit

[libc++] Remove _LIBCPP_DISABLE_NODISCARD_EXTENSIONS and refactor the tests (#87094 )

2024-04-22 22:13:58 +02:00

__charconv

[libc++][NFC] Replace _NOEXCEPT and _LIBCPP_CONSTEXPR macros with the keywords in C++11 code (#96387 )

2024-06-23 22:03:41 +02:00

__chrono

[libc++][NFC] Replace _NOEXCEPT and _LIBCPP_CONSTEXPR macros with the keywords in C++11 code (#96387 )

2024-06-23 22:03:41 +02:00

__compare

[libc++] P2602R2 Poison Pills are Too Toxic (#74534 )

2024-03-16 12:16:36 +00:00

__concepts

[libc++][ranges] remove __workaround_52970 (#85683 )

2024-03-20 09:49:31 +01:00

__condition_variable

[libc++] Split the monolithic __threading_support header (#79654 )

2024-01-30 08:35:15 -05:00

__configuration

[libc++] Fix deployment target Lit features (#94791 )

2024-06-21 10:31:22 -04:00

__coroutine

[libc++][hardening] Classify assertions related to leaks and syscalls. (#77164 )

2024-01-22 18:12:58 -08:00

__debug_utils

[libc++][NFC] Move basic ASan annotation functions into a utility header (#87220 )

2024-04-13 18:24:12 +02:00

__exception

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

__expected

[libc++] restrict the expected conversion constructor not compete against copy constructor (#96101 )

2024-06-26 12:10:59 +01:00

__filesystem

[libc++] Make the __availability header a sub-header of __config (#93083 )

2024-05-28 18:29:11 -07:00

__format

[libc++] Properly define _LIBCPP_HAS_NO_UNICODE in __config_site (#95138 )

2024-06-18 14:22:33 -04:00

__functional

[libc++][NFC] Replace _NOEXCEPT and _LIBCPP_CONSTEXPR macros with the keywords in C++11 code (#96387 )

2024-06-23 22:03:41 +02:00

__fwd

[libc++] Make the __availability header a sub-header of __config (#93083 )

2024-05-28 18:29:11 -07:00

__ios

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

__iterator

[libc++][NFC] Replace _NOEXCEPT and _LIBCPP_CONSTEXPR macros with the keywords in C++11 code (#96387 )

2024-06-23 22:03:41 +02:00

__locale_dir

[libc++] Enable modernize-use-equals-delete (#93293 )

2024-06-18 10:51:57 +02:00

__math

[libc++][NFC] Remove unnecessary parens in static_asserts (#95605 )

2024-06-18 10:45:30 +02:00

__mdspan

[libc++] P3029R1: Better mdspan's CTAD - std::extents (#89015 )

2024-06-25 10:20:14 -05:00

__memory

"[libc++] Try again LWG3233 Broken requirements for shared_ptr converting constructors" (#96103 )

2024-06-26 07:47:39 +01:00

__memory_resource

[libc++] Make the __availability header a sub-header of __config (#93083 )

2024-05-28 18:29:11 -07:00

__mutex

[libc++] Enable modernize-use-equals-delete (#93293 )

2024-06-18 10:51:57 +02:00

__numeric

[libc++] Fix incorrect overflow checking in std::lcm (#96310 )

2024-06-25 08:35:23 -05:00

__ostream

[libc++] Enable modernize-use-equals-delete (#93293 )

2024-06-18 10:51:57 +02:00

__pstl

[libc++] Remove unnecessary #ifdef guards around PSTL implementation details (#95268 )

2024-06-12 17:25:43 -04:00

__random

[libc++][NFC] Replace _NOEXCEPT and _LIBCPP_CONSTEXPR macros with the keywords in C++11 code (#96387 )

2024-06-23 22:03:41 +02:00

__ranges

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

__stop_token

[libc++] Make the __availability header a sub-header of __config (#93083 )

2024-05-28 18:29:11 -07:00

__string

[libc++][NFC] Replace _NOEXCEPT and _LIBCPP_CONSTEXPR macros with the keywords in C++11 code (#96387 )

2024-06-23 22:03:41 +02:00

__support

[libc++] Don't give functions C linkage (#94102 )

2024-06-02 21:05:53 +02:00

__system_error

[libc++] Undeprecate POSIX STREAM macros. (#88296 )

2024-04-13 13:46:34 +02:00

__thread

[libc++] Enable modernize-use-equals-delete (#93293 )

2024-06-18 10:51:57 +02:00

__tuple

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

__type_traits

[libc++] Use _If for conditional_t (#96193 )

2024-06-25 16:53:17 +02:00

__utility

[libc++][NFC] Simplify pair a bit (#96165 )

2024-06-26 10:51:45 +02:00

__variant

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

experimental

[libc++][NFC] Replace _NOEXCEPT and _LIBCPP_CONSTEXPR macros with the keywords in C++11 code (#96387 )

2024-06-23 22:03:41 +02:00

ext

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

__assert

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

__bit_reference

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

__config

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

__config_site.in

[libc++] Properly define _LIBCPP_HAS_NO_UNICODE in __config_site (#95138 )

2024-06-18 14:22:33 -04:00

__hash_table

[libc++] Refactor<__type_traits/is_swappable.h> (#86822 )

2024-06-18 11:01:43 +02:00

__locale

[libc++] Mark more types as trivially relocatable (#89724 )

2024-06-17 13:09:04 +02:00

__mbstate_t.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

__node_handle

[libc++] Remove _LIBCPP_DISABLE_NODISCARD_EXTENSIONS and refactor the tests (#87094 )

2024-04-22 22:13:58 +02:00

__split_buffer

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

__std_clang_module

[libc++] Remove experimental pmr headers now shipped in mainline (#73172 )

2023-11-27 10:54:35 -05:00

__std_mbstate_t.h

…

__tree

[libc++] Refactor<__type_traits/is_swappable.h> (#86822 )

2024-06-18 11:01:43 +02:00

__undef_macros

Fixing conflicting macro definitions between curses.h and the standard library.

2023-07-06 17:21:08 +00:00

__verbose_abort

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

algorithm

[libc++][pstl] Merge all frontend functions for the PSTL (#89219 )

2024-05-27 17:51:12 -04:00

any

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

array

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

atomic

[libc++] Implement C++20 atomic_ref (#76647 )

2024-05-21 15:54:08 -07:00

barrier

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

bit

[libc++][RFC] Only include what is required by-version in the umbrella headers (#83740 )

2024-04-14 15:52:56 +02:00

bitset

[libc++] Fix failures with GCC 14 (#92663 )

2024-06-01 12:20:41 +02:00

cassert

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

ccomplex

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

cctype

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

cerrno

[libc++] Undeprecate POSIX STREAM macros. (#88296 )

2024-04-13 13:46:34 +02:00

cfenv

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

cfloat

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

charconv

[libc++][RFC] Only include what is required by-version in the umbrella headers (#83740 )

2024-04-14 15:52:56 +02:00

chrono

[libc++] Remove <ostream> include from <chrono> (#96035 )

2024-06-20 21:40:23 +02:00

cinttypes

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

ciso646

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

climits

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

clocale

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

CMakeLists.txt

[libc++] Overhaul the PSTL dispatching mechanism (#88131 )

2024-06-12 12:24:34 -04:00

cmath

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

codecvt

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

compare

[libc++][RFC] Only include what is required by-version in the umbrella headers (#83740 )

2024-04-14 15:52:56 +02:00

complex

[libc++][NFC] Use the tuple forward declaration header for tuple forward declarations

2024-03-16 15:47:17 +01:00

complex.h

…

concepts

[libc++][RFC] Only include what is required by-version in the umbrella headers (#83740 )

2024-04-14 15:52:56 +02:00

condition_variable

[libc++] Make the __availability header a sub-header of __config (#93083 )

2024-05-28 18:29:11 -07:00

coroutine

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

csetjmp

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

csignal

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

cstdarg

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

cstdbool

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

cstddef

[libc++] Remove _LIBCPP_DISABLE_NODISCARD_EXTENSIONS and refactor the tests (#87094 )

2024-04-22 22:13:58 +02:00

cstdint

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

cstdio

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

cstdlib

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

cstring

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

ctgmath

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

ctime

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

ctype.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

cuchar

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

cwchar

[libc++][NFC] Replace __apply_cv with __copy_cv or __copy_cvref (#90867 )

2024-05-10 20:06:21 +02:00

cwctype

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

deque

[libc++] Move allocator assertion into allocator_traits (#94750 )

2024-06-25 10:13:48 -05:00

errno.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

exception

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

execution

[libc++] Simplify the implementation of remove_reference (#85207 )

2024-03-18 13:57:07 +01:00

expected

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

fenv.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

filesystem

[libc++] Rename __fwd/hash.h to __fwd/functional.h and add reference_wrapper (#81445 )

2024-03-03 20:45:17 +01:00

float.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

format

[libc++][format] Improves escaping performance. (#88533 )

2024-04-28 12:15:25 +02:00

forward_list

[libc++] Move allocator assertion into allocator_traits (#94750 )

2024-06-25 10:13:48 -05:00

fstream

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

functional

[libc++][functional] P2944R3 (partial): Comparisons for reference_wrapper (reference_wrapper operators only) (#88384 )

2024-05-09 12:48:37 +03:00

future

[libc++][NFC] Replace _NOEXCEPT and _LIBCPP_CONSTEXPR macros with the keywords in C++11 code (#96387 )

2024-06-23 22:03:41 +02:00

initializer_list

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

inttypes.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

iomanip

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

ios

[libc++][NFC] Remove unnecessary parens in static_asserts (#95605 )

2024-06-18 10:45:30 +02:00

iosfwd

[libc++] Enable modernize-use-equals-delete (#93293 )

2024-06-18 10:51:57 +02:00

iostream

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

istream

[libc++] Enable modernize-use-equals-delete (#93293 )

2024-06-18 10:51:57 +02:00

iterator

[libc++][ranges] LWG3736: move_iterator missing disable_sized_sentinel_for specialization (#85611 )

2024-04-12 10:09:05 -04:00

latch

[libc++] Make the __availability header a sub-header of __config (#93083 )

2024-05-28 18:29:11 -07:00

limits

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

list

[libc++] Move allocator assertion into allocator_traits (#94750 )

2024-06-25 10:13:48 -05:00

locale

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

locale.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

map

[libc++] Move allocator assertion into allocator_traits (#94750 )

2024-06-25 10:13:48 -05:00

math.h

[libc++] Remove _LIBCPP_DISABLE_NODISCARD_EXTENSIONS and refactor the tests (#87094 )

2024-04-22 22:13:58 +02:00

mdspan

[libc++] P3029R1: Better mdspan's CTAD (#87873 )

2024-04-12 19:25:22 +02:00

memory

[libc++] Undeprecate shared_ptr atomic access APIs (#92920 )

2024-06-07 11:31:17 -04:00

memory_resource

[libc++] Remove a few transitive includes (#70553 )

2023-10-29 18:31:37 +01:00

module.modulemap

[libc++] Overhaul the PSTL dispatching mechanism (#88131 )

2024-06-12 12:24:34 -04:00

mutex

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

new

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

numbers

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

numeric

[libc++][pstl] Merge all frontend functions for the PSTL (#89219 )

2024-05-27 17:51:12 -04:00

optional

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

ostream

[libc++] Granularize <ostream> (#85537 )

2024-05-02 22:38:44 +02:00

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

queue

[libc++][NFC] Replace _NOEXCEPT and _LIBCPP_CONSTEXPR macros with the keywords in C++11 code (#96387 )

2024-06-23 22:03:41 +02:00

random

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

ranges

[libc++][ranges] P2387R3: Pipe support for user-defined range adaptors (#89148 )

2024-04-23 10:58:14 -04:00

ratio

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

regex

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

scoped_allocator

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

semaphore

[libc++] Make the __availability header a sub-header of __config (#93083 )

2024-05-28 18:29:11 -07:00

set

[libc++] Move allocator assertion into allocator_traits (#94750 )

2024-06-25 10:13:48 -05:00

shared_mutex

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

source_location

[libc++] Update <source_location> and msvc_stdlib_force_include.h (#74266 )

2023-12-06 09:04:06 -05:00

span

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

sstream

[libc++] Make the __availability header a sub-header of __config (#93083 )

2024-05-28 18:29:11 -07:00

stack

[libc++][NFC] Replace _NOEXCEPT and _LIBCPP_CONSTEXPR macros with the keywords in C++11 code (#96387 )

2024-06-23 22:03:41 +02:00

stdatomic.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

stdbool.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

stddef.h

[libc++] Fix -Wgnu-include-next in stddef.h (#88214 )

2024-04-11 12:36:56 -04:00

stdexcept

[NFC][libc++] Fixes comment indention.

2024-05-01 18:34:19 +02:00

stdint.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

stdio.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

stdlib.h

[libc++] Remove _LIBCPP_DISABLE_NODISCARD_EXTENSIONS and refactor the tests (#87094 )

2024-04-22 22:13:58 +02:00

stop_token

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

streambuf

[libc++][NFC] Remove unnecessary parens in static_asserts (#95605 )

2024-06-18 10:45:30 +02:00

string

[libc++] Move allocator assertion into allocator_traits (#94750 )

2024-06-25 10:13:48 -05:00

string_view

[libc++][NFC] Replace _NOEXCEPT and _LIBCPP_CONSTEXPR macros with the keywords in C++11 code (#96387 )

2024-06-23 22:03:41 +02:00

string.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

strstream

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

syncstream

[libc++] Granularize <ostream> (#85537 )

2024-05-02 22:38:44 +02:00

system_error

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

tgmath.h

…

thread

[libc++][NFC] Remove a few unused <__availablity> includes (#86126 )

2024-04-02 13:52:07 +02:00

tuple

[libc++][NFC] Replace _NOEXCEPT and _LIBCPP_CONSTEXPR macros with the keywords in C++11 code (#96387 )

2024-06-23 22:03:41 +02:00

type_traits

[libc++][NFC] Replace __apply_cv with __copy_cv or __copy_cvref (#90867 )

2024-05-10 20:06:21 +02:00

typeindex

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

typeinfo

[libc++] Upstream ptrauth support in libc++ and libc++abi (#84573 )

2024-04-03 08:04:43 -04:00

uchar.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

unordered_map

[libc++] Move allocator assertion into allocator_traits (#94750 )

2024-06-25 10:13:48 -05:00

unordered_set

[libc++] Move allocator assertion into allocator_traits (#94750 )

2024-06-25 10:13:48 -05:00

utility

[libc++] Clean up includes of <__assert> (#80091 )

2024-02-29 10:12:22 -05:00

valarray

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

variant

[libc++][NFC] Run clang-format on libcxx/include again (#95874 )

2024-06-18 09:13:45 -04:00

vector

[libc++] Move allocator assertion into allocator_traits (#94750 )

2024-06-25 10:13:48 -05:00

version

[libc++][modules] Mark as implemented. (#90091 )

2024-06-12 19:01:27 +02:00

wchar.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00

wctype.h

[libc++] Format the code base (#74334 )

2023-12-18 14:01:33 -05:00