std::declare_reachable

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< cpplrm; | memory
Dynamic memory management
Uninitialized storage
(C++17)
Garbage collection support
declare_reachable
(C++11)
Miscellaneous
(C++20)
(C++11)
(C++11)
C Library
Low level memory management
Defined in header <memory>
void declare_reachable( void* p );
(since C++11)

Declares the object referenced by the pointer p reachable. Reachable objects will not be deleted by the garbage collector or considered to be a leak by a leak detector even if all pointers to it are destroyed. An object may be declared reachable multiple times, in which case multiple calls to std::undeclare_reachable would be needed to remove this property. For example, a XOR linked list needs to declare its nodes reachable if the implementation has garbage collection enabled.

Parameters

p - a safely-derived pointer or a null pointer

Return value

(none)

Exceptions

May throw std::bad_alloc if the system cannot allocate memory required to track reachable objects.

Example

See also

declares that an object can be recycled
(function template)