http://gcc.gnu.org/viewcvs/trunk/libffi/ does not have a libffi.pc.in in its source tree, which that is present in the tree the code got imported from: http://sources.redhat.com/cgi-bin/cvsweb.cgi/libffi/?cvsroot=libffi
This caused issues elsewhere, e.g. https://bugzilla.gnome.org/show_bug.cgi?id=603653 -- Summary: pkg-config (.pc) file missing in libffi (lost during import) Product: gcc Version: 4.4.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libffi AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: ensonic at hora-obscura dot de http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42275