current trunk :

gfortran -c -O0 test.f90
test.f90: In function ‘pw_integral_a2b’:
test.f90:251: internal compiler error: in gfc_conv_variable, at
fortran/trans-expr.c:386
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://gcc.gnu.org/bugs.html> for instructions.


-- 
           Summary: nternal compiler error: in gfc_conv_variable, at
                    fortran/trans-expr.c:386
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jv244 at cam dot ac dot uk


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32242