Cite
 
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.