Cold-Air-Networks/mirror-llvm-project
2
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions 7

[libc++] Remove SFINAE checks in tuple which are always true (#212765)

Browse source 
We have a specialization for `tuple` with no arguments, so checking
`sizeof...(_Tp) >= 1` in the primary template will never be false.
This commit is contained in:
Nikolas Klauser 2026-07-30 11:17:08 +02:00 committed by GitHub
parent 6ddd80af0b
commit c27b35739d
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
1 changed files with 5 additions and 7 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

12
libcxx/include/tuple
View file

@ -591,15 +591,14 @@ public:
: __base_(allocator_arg_t(), __a, __value_init{}) {}
// tuple(const T&...) constructors (including allocator_arg_t variants)
template <template <class...> class _And = _And,
__enable_if_t< _And< _BoolConstant<sizeof...(_Tp) >= 1>, is_copy_constructible<_Tp>... >::value, int> = 0>
template <template <class...> class _And = _And, __enable_if_t<_And<is_copy_constructible<_Tp>...>::value, int> = 0>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(!_And<is_convertible<const _Tp&, _Tp>...>::value)
tuple(const _Tp&... __t) noexcept(_And<is_nothrow_copy_constructible<_Tp>...>::value)
: __base_(__forward_args{}, __t...) {}
template <class _Alloc,
template <class...> class _And = _And,
__enable_if_t< _And< _BoolConstant<sizeof...(_Tp) >= 1>, is_copy_constructible<_Tp>... >::value, int> = 0>
template <class...> class _And = _And,
__enable_if_t<_And<is_copy_constructible<_Tp>...>::value, int> = 0>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(!_And<is_convertible<const _Tp&, _Tp>...>::value)
tuple(allocator_arg_t, const _Alloc& __a, const _Tp&... __t)
: __base_(allocator_arg_t(), __a, __forward_args{}, __t...) {}
@ -612,9 +611,8 @@ public:
template <class... _Up>
struct _EnableUTypesCtor
: _And< _BoolConstant<sizeof...(_Tp) >= 1>,
_Not<_IsThisTuple<_Up...> >, // extension to allow mis-behaved user constructors
is_constructible<_Tp, _Up>... > {};
: _And<_Not<_IsThisTuple<_Up...> >, // extension to allow mis-behaved user constructors
is_constructible<_Tp, _Up>... > {};
template <class... _Up,
__enable_if_t< _And< _BoolConstant<sizeof...(_Up) == sizeof...(_Tp)>, _EnableUTypesCtor<_Up...> >::value,