[Bug fortran/78739] New: ICE in gfc_get_symbol_decl, at fortran/trans-decl.c:1477

["gerhard dot steinmetz dot fortran at t-online dot de" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78739

            Bug ID: 78739
           Summary: ICE in gfc_get_symbol_decl, at
                    fortran/trans-decl.c:1477
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gerhard.steinmetz.fortran@t-online.de
  Target Milestone: ---

A tiny snippet of _invalid_ code, ICEs down to at least 4.8.
Backtrace similar to that of pr68846 comment 4 and pr70864 comment 3.


$ cat z1.f90
function f(n)
   f() = n
end


$ gfortran-7-20161204 -c z1.f90
z1.f90:1:0:

 function f(n)

internal compiler error: in gfc_get_symbol_decl, at fortran/trans-decl.c:1477
0x75a352 gfc_get_symbol_decl(gfc_symbol*)
        ../../gcc/fortran/trans-decl.c:1477
0x75e5b7 generate_local_decl
        ../../gcc/fortran/trans-decl.c:5327
0x71825b do_traverse_symtree
        ../../gcc/fortran/symbol.c:3994
0x75f412 generate_local_vars
        ../../gcc/fortran/trans-decl.c:5527
0x75f412 gfc_generate_function_code(gfc_namespace*)
        ../../gcc/fortran/trans-decl.c:6206
0x6e73d0 translate_all_program_units
        ../../gcc/fortran/parse.c:6038
0x6e73d0 gfc_parse_file()
        ../../gcc/fortran/parse.c:6238
0x72b182 gfc_be_parse_file
        ../../gcc/fortran/f95-lang.c:202