http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54797
--- Comment #3 from Steve Kargl <sgk at troutmask dot apl.washington.edu> 2012-10-03 19:55:46 UTC --- On Wed, Oct 03, 2012 at 07:37:24PM +0000, christopher.romick at gmail dot com wrote: > > I have indeed tried include -I but it makes no differences. The compilation > returns the same error. > > The 1st line states > > GFORTRAN module created from /.../odesolver/LSODE/datodesol.f90 on Wed Oct 3 > 15:35:10 2012 > > of course the ... is the rest of the full path > Which version of gfortran? With version 4.4.x and above you should have a version number. % gfc44 -c a.f90 && head -1 a.mod GFORTRAN module version '0' created from a.f90 on Wed Oct 3 12:50:55 2012 % gfc45 -c a.f90 && head -1 a.mod GFORTRAN module version '4' created from a.f90 on Wed Oct 3 12:51:00 2012 % gfc46 -c a.f90 && head -1 a.mod GFORTRAN module version '6' created from a.f90 on Wed Oct 3 12:51:04 2012 % gfc47 -c a.f90 && head -1 a.mod GFORTRAN module version '9' created from a.f90 % gfc4x -c a.f90 && head -1 a.mod GFORTRAN module version '9' created from a.f90 Do you have more than one version of gfortran installed on the system? It appears as if you are building the module with an older gfortran and trying to use with a newer version.