http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57653
--- Comment #7 from Manuel López-Ibáñez <manu at gcc dot gnu.org> --- (In reply to Allan McRae from comment #6) > I have also confirmed this issue on Fedora rawhide. > > gcc 4.8.1 20130603 (Red Hat 4.8.1-1) What I would do to investigate this issue is to put a breakpoint in linemap_add and try to figure out what is the difference with and without the -imacro. There must be some difference there.