An FFM message indicates that the program is trying to free memory that has previously been freed.
This message can occur when one function frees the memory, but a data structure retains a pointer to that memory and later a different function tries to free the same memory. This message can also occur if the heap is corrupted.
Note:
§ Purify does not put VirtualFree calls onto the deferred free queue. Consequently, Purify reports a Bad Parameter (PAR) message or a Freeing Invalid Memory (FIM) message and not a FFM message if the program frees freed memory using VirtualFree.
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