[Bug fortran/60898] model compile error with gfortran 4.7 and gcc 4.9 on Mac OS 10.9

[dominiq at lps dot ens.fr]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60898

--- Comment #8 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
Backtrace for the reduced test case

* thread #1: tid = 0x1357c7a, 0x00000001000afb00
f951`count_st_nodes(st=<unavailable>) + 16 at symbol.c:3580, queue =
'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x9)
    frame #0: 0x00000001000afb00 f951`count_st_nodes(st=<unavailable>) + 16 at
symbol.c:3580
   3577      if (!st)
   3578        return 0;
   3579    
-> 3580      nodes = count_st_nodes (st->left);
   3581      nodes++;
   3582      nodes += count_st_nodes (st->right);
   3583    
(lldb) bt
* thread #1: tid = 0x1357c7a, 0x00000001000afb00
f951`count_st_nodes(st=<unavailable>) + 16 at symbol.c:3580, queue =
'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x9)
  * frame #0: 0x00000001000afb00 f951`count_st_nodes(st=<unavailable>) + 16 at
symbol.c:3580
    frame #1: 0x00000001000afb09 f951`count_st_nodes(st=<unavailable>) + 25 at
symbol.c:3580
    frame #2: 0x00000001000afb09 f951`count_st_nodes(st=<unavailable>) + 25 at
symbol.c:3580
    frame #3: 0x00000001000afb09 f951`count_st_nodes(st=<unavailable>) + 25 at
symbol.c:3580
    frame #4: 0x00000001000afb09 f951`count_st_nodes(st=<unavailable>) + 25 at
symbol.c:3580
    frame #5: 0x00000001000afb09 f951`count_st_nodes(st=<unavailable>) + 25 at
symbol.c:3580
    frame #6: 0x00000001000afb09 f951`count_st_nodes(st=<unavailable>) + 25 at
symbol.c:3580
    frame #7: 0x00000001000afb09 f951`count_st_nodes(st=<unavailable>) + 25 at
symbol.c:3580
    frame #8: 0x00000001000b1a61 f951`do_traverse_symtree(st=<unavailable>,
st_func=0x0000000000000000, sym_func=0x00000001000f6040) + 49 at symbol.c:3617
    frame #9: 0x00000001000f7255
f951`gfc_generate_function_code(ns=0x0000000142052e00) + 373 at
trans-decl.c:5126
    frame #10: 0x00000001000cb9b2
f951`gfc_generate_module_code(ns=<unavailable>) + 466 at trans.c:1998
    frame #11: 0x00000001000817c3 f951`gfc_parse_file() + 167 at parse.c:4934
    frame #12: 0x000000010008171c f951`gfc_parse_file() + 1116
    frame #13: 0x00000001000c4c56 f951`gfc_be_parse_file + 38 at f95-lang.c:212
    frame #14: 0x00000001008ba397 f951`compile_file + 39 at toplev.c:548
    frame #15: 0x00000001008bcbbf f951`toplev_main(argc=2,
argv=0x00007fff5fbff440) + 3327 at toplev.c:1946