http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20385
--- Comment #7 from Manuel López-Ibáñez <manu at gcc dot gnu.org> 2010-11-15 16:10:31 UTC --- And what about the undefined return type? unknowntype f() { return 0; } unknowntype *f() { return 0; } If you fix this bug once and for all, please mention it in gcc-4.6/changes.html, because this is a very significant improvement!