18 Language support library [language.support]

18.6 Dynamic memory management [support.dynamic]

18.6.1 Storage allocation and deallocation [new.delete]

18.6.1.3 Placement forms [new.delete.placement]

These functions are reserved, a C++ program may not define functions that displace the versions in the Standard C++ library ([constraints]). The provisions of ([basic.stc.dynamic]) do not apply to these reserved placement forms of operator new and operator delete.

void* operator new(std::size_t size, void* ptr) noexcept;

Returns: ptr.

Remarks: Intentionally performs no other action.

Example: This can be useful for constructing an object at a known address:

void* place = operator new(sizeof(Something));
Something* p = new (place) Something();

 — end example ]

void* operator new[](std::size_t size, void* ptr) noexcept;

Returns: ptr.

Remarks: Intentionally performs no other action.

void operator delete(void* ptr, void*) noexcept;

Effects: Intentionally performs no action.

Requires: If an implementation has strict pointer safety ([basic.stc.dynamic.safety]) then ptr shall be a safely-derived pointer.

Remarks: Default function called when any part of the initialization in a placement new expression that invokes the library's non-array placement operator new terminates by throwing an exception ([expr.new]).

void operator delete[](void* ptr, void*) noexcept;

Effects: Intentionally performs no action.

Requires: If an implementation has strict pointer safety ([basic.stc.dynamic.safety]) then ptr shall be a safely-derived pointer.

Remarks: Default function called when any part of the initialization in a placement new expression that invokes the library's array placement operator new terminates by throwing an exception ([expr.new]).