[Bug debug/37287] New: [4.4 Regression] ICE (segfault) with new debugging patch

["burnus at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

Seemingly, we overlooked some issue when checking the debug patches. Compiling
octopus (tddft.org) with gfortran now gives an ICE:

$ gfortran -g tmp1.f90 tmp.f90
tmp.f90:2: internal compiler error: Segmentation fault

Valgrind shows (when compiling tmp.f90, tmp1.f90 is OK):

==8754== Invalid read of size 1
==8754==    at 0xB5B660: htab_hash_string (hashtab.c:812)
==8754==    by 0x54B12E: lookup_filename (dwarf2out.c:15573)
==8754==    by 0x557B86: add_src_coords_attributes (dwarf2out.c:12442)
==8754==    by 0x558B1A: add_name_and_src_coords_attributes (dwarf2out.c:12459)
==8754==    by 0x560FC0: gen_decl_die (dwarf2out.c:15040)
==8754==    by 0x563BD7: force_decl_die (dwarf2out.c:14940)
==8754==    by 0x56559C: dwarf2out_imported_module_or_decl (dwarf2out.c:15344)
==8754==    by 0x4A15DC: gfc_trans_use_stmts (trans-decl.c:3178)
==8754==    by 0x4A180E: gfc_generate_module_vars (trans-decl.c:3385)
==8754==    by 0x48F07C: gfc_generate_module_code (trans.c:1226)


Test files (note: There is no ICE if one puts the two files into a single
file).

---------- tmp1.f90 -------------
module c_pointer_m
  use iso_c_binding, only : c_ptr, c_associated, c_null_ptr
  implicit none
contains
  subroutine set_null(ptr)
      type(c_ptr), intent(out) :: ptr
      ptr = c_null_ptr
  end subroutine set_null
end module c_pointer_m

------------ tmp.f90 ---------------
module string_m
  use c_pointer_m
  implicit none
end module string_m


-- 
           Summary: [4.4 Regression] ICE (segfault) with new debugging patch
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: debug
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: burnus at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37287