Source : Free On-Line Dictionary of Computing

stale pointer bug
     
         (Or "aliasing bug") A class of subtle
        programming errors that can arise in code that does {dynamic
        allocation}, especially via {malloc} or equivalent.
     
        If several {pointers} address (are "aliases for") a given hunk
        of storage, it may happen that the storage is freed or
        reallocated (and thus moved) through one alias and then
        referenced through another, which may lead to subtle (and
        possibly intermittent) lossage depending on the state and the
        allocation history of the malloc {arena}.  This bug can be
        avoided by never creating aliases for allocated memory, or by
        use of a {higher-level language}, such as {Lisp}, which
        employs a {garbage collector}.
     
        The term "aliasing bug" is nowadays associated with {C}
        programming, it was already in use in a very similar sense in
        the {ALGOL 60} and {Fortran} communities in the 1960s.
     
        See also {smash the stack}, {fandango on core}, {memory leak},
        {memory smash}, {spam}.
     
        [{Jargon File}]
     
        (1995-05-09)