Remove unneeded check if (this != _STD addressof(_Right))

[fsb4000]

Fixes #3538

[DenisYaroshevskiy]

What about a move assignment above the one you fixed. Can you delete it?

STL/stl/inc/memory

Line 3256 in 994f941

_CONSTEXPR23 unique_ptr& operator=(unique_ptr<_Ty2, _Dx2>&& _Right) noexcept {

[fsb4000]

Can you delete it?

No.

Look at https://eel.is/c++draft/unique.ptr.single.asgn

We must have 3 assignment operators.

constexpr unique_ptr& operator=(unique_ptr&& u) noexcept;

Constraints: is_­move_­assignable_­v is true.

STL/stl/inc/memory

Lines 3262 to 3269 in 994f941

	template <class _Dx2 = _Dx, enable_if_t<is_move_assignable_v<_Dx2>, int> = 0>
	_CONSTEXPR23 unique_ptr& operator=(unique_ptr&& _Right) noexcept {
	if (this != _STD addressof(_Right)) {
	reset(_Right.release());
	_Mypair._Get_first() = _STD forward<_Dx>(_Right._Mypair._Get_first());
	}
	return *this;
	}

template<class U, class E> constexpr unique_ptr& operator=(unique_ptr<U, E>&& u) noexcept;

Constraints:

unique_­ptr<U, E>​::​pointer is implicitly convertible to pointer, and
U is not an array type, and
is_­assignable_­v<D&, E&&> is true.

STL/stl/inc/memory

Lines 3252 to 3260 in 994f941

	template <class _Ty2, class _Dx2,
	enable_if_t<conjunction_v<negation<is_array<_Ty2>>, is_assignable<_Dx&, _Dx2>,
	is_convertible<typename unique_ptr<_Ty2, _Dx2>::pointer, pointer>>,
	int> = 0>
	_CONSTEXPR23 unique_ptr& operator=(unique_ptr<_Ty2, _Dx2>&& _Right) noexcept {
	reset(_Right.release());
	_Mypair._Get_first() = _STD forward<_Dx2>(_Right._Mypair._Get_first());
	return *this;
	}

constexpr unique_ptr& operator=(nullptr_t) noexcept;

STL/stl/inc/memory

Lines 3212 to 3215 in 994f941

	_CONSTEXPR23 unique_ptr& operator=(nullptr_t) noexcept {
	reset();
	return *this;
	}

[DenisYaroshevskiy]

I see, appreciate it

[StephanTLavavej]

I'm mirroring this to the MSVC-internal repo - please notify me if any further changes are pushed.

[StephanTLavavej]

Thanks for eliminating this branch in a widely used member function! 🌴 🪓 😸