nasal demons

nasal demons

Recognised shorthand on the Usenet group comp.std.c for anyunexpected behaviour of a C compiler on encountering anundefined construct. During a discussion on that group inearly 1992, a regular remarked "When the compiler encounters[a given undefined construct] it is legal for it to makedemons fly out of your nose" (the implication is that thecompiler may choose any arbitrarily bizarre way to interpretthe code without violating the ANSI C standard). Someoneelse followed up with a reference to "nasal demons", whichquickly became established.