overrun screw n.
[C programming] A variety of fandango on core produced by
scribbling past the end of an array (C implementations typically
have no checks for this error). This is relatively benign and
easy to spot if the array is static; if it is auto, the result
may be to smash the
stack -- often resulting in heisenbugs of the most diabolical subtlety.
The term `overrun screw' is used esp. of scribbles beyond the end
of arrays allocated with malloc(3); this typically
trashes the allocation header for the next block in the arena, producing massive lossage within
malloc and often a core dump on the next operation to use
stdio(3) or malloc(3) itself. See spam, overrun;
see also memory leak, memory smash, aliasing bug, precedence lossage, fandango on core, secondary damage.