$ cat a.f90 program test implicit none real(8) :: x external bug x = 2 print *, bug(x) end program test
$ gfortran -c a.f90 a.f90: In function ‘MAIN__’: a.f90:7: internal compiler error: in gfc_typenode_for_spec, at fortran/trans-types.c:613 -- Summary: ICE on invalid use of external keyword Product: gcc Version: 4.0.0 Status: UNCONFIRMED Severity: normal Priority: P2 Component: fortran AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: coudert at clipper dot ens dot fr CC: gcc-bugs at gcc dot gnu dot org GCC host triplet: i686-unkown-linux http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18737