std::declare_reachable

 

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Defined in header <memory>
void declare_reachable( void* p );		(since C++11) (removed in C++23)

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.

See also

undeclare_reachable (C++11)(removed in C++23)

declares that an object can be recycled (function template)