[Bug fortran/50408] [4.6/4.7 regression] ICE in transfer_expr

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50408

--- Comment #3 from Tobias Burnus <burnus at gcc dot gnu.org> 2011-11-24 
22:13:06 UTC ---
That a -fwhole-file regression, which became the default in 4.6. The work
around is -fno-whole-file.

The problem is in gfc_get_extern_function_decl:

      gfc_find_symbol (sym->name, gsym->ns, 0, &s);
      if (s && s->backend_decl)
        {
          sym->backend_decl = s->backend_decl;
          return sym->backend_decl;
        }

The problem is that this does not set
  sym->ts.u.derived{,->components{,->next}}->backend_decl
for BT_DERIVED/BT_CLASS; one might also need to update
  sym->ts.u.cl...
for BT_CHARACTER.

Note: There are more places in trans*.c which call gfc_find_gsymbol