std::declare_reachable
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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.
Contents
[edit] Parameters
p
-
a safely-derived pointer or a null pointer
[edit] Return value
(none)
[edit] Exceptions
May throw std::bad_alloc if the system cannot allocate memory required to track reachable objects.