missing module file results in a fatal error noting the missing module, and then an ICE in f951.
sample source program testmytypes use mytypes implicit none real(dp)::x=5. write(*,"(e13.6,' squared = ',e13.6)")x,x**2 end program testmytypes Output: F:\brad\class\engr325>gfortran bugtest.f90 bugtest.f90:2.13: use mytypes 1 Fatal Error: Can't open module file 'mytypes.mod' for reading at (1): No such file or directory gfortran: internal compiler error: Aborted (program f951) Please submit a full bug report, with preprocessed source if appropriate. See <http://gcc.gnu.org/bugs.html> for instructions. -- Summary: ICE on missing module file Product: gcc Version: 4.6.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: fortran AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: brad dot finney at humboldt dot edu GCC build triplet: i586-pc-mingw32 GCC host triplet: i586-pc-mingw32 GCC target triplet: i586-pc-mingw32 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45575