Skip to content

implement LWG-3527 #2194

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
StephanTLavavej merged 4 commits into from
Sep 11, 2021
Merged

implement LWG-3527 #2194

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
56a9632
implement LWG3527
fsb4000 Sep 9, 2021
b545849
move test code to P0475R1_P0591R4_uses_allocator_construction
fsb4000 Sep 9, 2021
68818c7
p is actually used :)
fsb4000 Sep 9, 2021
0f8b0c1
Code review feedback.
StephanTLavavej Sep 9, 2021
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
6 changes: 3 additions & 3 deletions stl/inc/xmemory
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2140,10 +2140,10 @@ template <class _Ty, class _Alloc, class _Uty1, class _Uty2, enable_if_t<_Is_spe
_NODISCARD constexpr auto uses_allocator_construction_args(const _Alloc& _Al, pair<_Uty1, _Uty2>&& _Pair) noexcept {
// equivalent to
// return _STD uses_allocator_construction_args<_Ty>(_Al, piecewise_construct,
// _STD forward_as_tuple(_STD move(_Pair).first), _STD forward_as_tuple(_STD move(_Pair).second));
// _STD forward_as_tuple(_STD get<0>(_STD move(_Pair)), _STD forward_as_tuple(_STD get<1>(_STD move(_Pair)));
return _STD make_tuple(piecewise_construct,
_STD uses_allocator_construction_args<typename _Ty::first_type>(_Al, _STD move(_Pair).first),
_STD uses_allocator_construction_args<typename _Ty::second_type>(_Al, _STD move(_Pair).second));
_STD uses_allocator_construction_args<typename _Ty::first_type>(_Al, _STD get<0>(_STD move(_Pair))),
_STD uses_allocator_construction_args<typename _Ty::second_type>(_Al, _STD get<1>(_STD move(_Pair))));
}

template <class _Ty, class _Alloc, class... _Types>
Expand Down
12 changes: 12 additions & 0 deletions tests/std/tests/P0475R1_P0591R4_uses_allocator_construction/test.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -179,6 +179,18 @@ void test_GH_2021() { // COMPILE-ONLY
tags[0];
}

struct MoveOnlyType {
MoveOnlyType() = default;
MoveOnlyType(MoveOnlyType&&) = default;
};

void test_LWG3527() { // COMPILE-ONLY
allocator<MoveOnlyType> alloc;
MoveOnlyType obj;
pair<MoveOnlyType&&, MoveOnlyType&&> p{move(obj), move(obj)};
[[maybe_unused]] auto t = uses_allocator_construction_args<pair<MoveOnlyType&&, MoveOnlyType&&>>(alloc, move(p));
}

int main() {
test_P0475R1();

Expand Down