[Bug fortran/53818] -finit-local-zero -fno-automatic: Function result cannot have initializer

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

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53818

Tobias Burnus <burnus at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |rejects-valid
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2012-06-30
                 CC|                            |burnus at gcc dot gnu.org
            Summary|-fno-automatic cannot have  |-finit-local-zero
                   |initializer                 |-fno-automatic: Function
                   |                            |result cannot have
                   |                            |initializer
     Ever Confirmed|0                           |1

--- Comment #3 from Tobias Burnus <burnus at gcc dot gnu.org> 2012-06-30 14:31:29 UTC ---
(In reply to comment #0)
> But when I integrate '-fno-automatic' option, I obtain this error message :
> function testing(date1, date2) result(test)
>                                           1
> Error: Function result 'test' at (1) cannot have an initializer

I helps if you tell up all options. The issue seemingly only occurs with
-fno-automatic *and* -finit-local-zero (or -finit-logical=true|false).


Two things surprise me:

a) Why are there two initializer, when looking at the dump
(-fdump-tree-original). (Requires that one does not have -fno-automatic) - the
should be only one, shouldn't it?


b) Why does this only trigger with -fno-automatic? The code currently has the
following. At a glance, it should always trigger and the
apply_default_init_local should be after the checks (together with the
simplify):

resolve_fl_variable (gfc_symbol *sym, int mp_flag)
...
  if (sym->value == NULL && sym->attr.referenced)
    apply_default_init_local (sym); /* Try to apply a default initialization. 
*/
...
  /* Reject illegal initializers.  */
  if (!sym->mark && sym->value)
...
      else if (sym->attr.result)
        gfc_error ("Function result '%s' at %L cannot have an initializer",
                   sym->name, &sym->declared_at);