[Bug fortran/88249] New: ICE in gfc_resolve_filepos, at fortran/io.c:2853

[gscfq@t-online.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88249

            Bug ID: 88249
           Summary: ICE in gfc_resolve_filepos, at fortran/io.c:2853
           Product: gcc
           Version: 9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gscfq@t-online.de
  Target Milestone: ---

With a missing file-unit-number, down to at least gcc-5 :


$ cat z1.f90
program p
   backspace (err=1)
   endfile (err=1)
   flush (err=1)
   rewind (err=1)
end


$ gfortran-9-20181125 -c z1.f90
f951: internal compiler error: Segmentation fault
0xb2bcff crash_signal
        ../../gcc/toplev.c:326
0x63f696 gfc_resolve_filepos(gfc_filepos*)
        ../../gcc/fortran/io.c:2853
0x6850ab gfc_resolve_code(gfc_code*, gfc_namespace*)
        ../../gcc/fortran/resolve.c:11547
0x68702f resolve_codes
        ../../gcc/fortran/resolve.c:16704
0x6870fe gfc_resolve(gfc_namespace*)
        ../../gcc/fortran/resolve.c:16739
0x674e87 resolve_all_program_units
        ../../gcc/fortran/parse.c:6064
0x674e87 gfc_parse_file()
        ../../gcc/fortran/parse.c:6314
0x6bdaff gfc_be_parse_file
        ../../gcc/fortran/f95-lang.c:204