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dangling pointer

A pointer that still holds the address of something that has already been freed or has gone out of scope.

A dangling pointer refers to storage whose lifetime has ended (a freed heap block, a returned function's stack slot); dereferencing it is undefined behaviour and may read stale data, data of a newer object at the same address, or fault.

Examples

  • Returning the address of a local variable gives the caller a dangling pointer.

See also

use-after-free stack slot heap undefined behaviour
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