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double free

Freeing the same heap block twice, which confuses the memory allocator's own records.

A double free passes an already freed pointer to free/delete again, corrupting the allocator's metadata; many allocators detect common cases and abort the process with a diagnostic.

Examples

  • free(p); free(p); frees the same block twice; glibc often stops the program with a "double free detected" message.

See also

heap corruption heap
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