pessimal
= P =
peta-
pessimizing compiler /pes'*-mi:z`ing k*m-pi:l'r/ n.
[antonym of techspeak `optimizing compiler'] A compiler that
produces object code that is worse than the straightforward or
obvious hand translation. The implication is that the compiler is
actually trying to optimize the program, but through excessive
cleverness is doing the opposite. A few pessimizing compilers have
been written on purpose, however, as pranks or burlesques.
--The Jargon File version 4.3.1, ed. ESR, autonoded by rescdsk.