[Bug fortran/50923] [4.4/4.5/4.6/4.7 Regression] No warning if function return value is not set

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50923

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2011-11-05
     Ever Confirmed|0                           |1

--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-11-05 
12:11:18 UTC ---
The fortran frontend emits

f ()
{

}

in this the middle-end does not warn because TREE_NO_WARNING is set
on the function decl by the frontend:

      if (result == NULL_TREE)
        {
          /* TODO: move to the appropriate place in resolve.c.  */
          if (warn_return_type && !sym->attr.referenced && sym == sym->result)
            gfc_warning ("Return value of function '%s' at %L not set",
                         sym->name, &sym->declared_at);

          TREE_NO_WARNING(sym->backend_decl) = 1;