From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <sgk@troutmask.apl.washington.edu>
Received: from troutmask.apl.washington.edu (troutmask.apl.washington.edu
 [128.95.76.21])
 by sourceware.org (Postfix) with ESMTPS id 898003840C0C
 for <fortran@gcc.gnu.org>; Tue, 28 Jul 2020 15:58:17 +0000 (GMT)
DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 898003840C0C
Received: from troutmask.apl.washington.edu (localhost [127.0.0.1])
 by troutmask.apl.washington.edu (8.16.1/8.16.1) with ESMTPS id 06SFwGuF076949
 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO)
 for <fortran@gcc.gnu.org>; Tue, 28 Jul 2020 08:58:16 -0700 (PDT)
 (envelope-from sgk@troutmask.apl.washington.edu)
Received: (from sgk@localhost)
 by troutmask.apl.washington.edu (8.16.1/8.16.1/Submit) id 06SFwG02076948
 for fortran@gcc.gnu.org; Tue, 28 Jul 2020 08:58:16 -0700 (PDT)
 (envelope-from sgk)
Date: Tue, 28 Jul 2020 08:58:16 -0700
From: Steve Kargl <sgk@troutmask.apl.washington.edu>
To: fortran@gcc.gnu.org
Subject: PR96325 should be high priority 
Message-ID: <20200728155816.GA76888@troutmask.apl.washington.edu>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
X-Spam-Status: No, score=-2.2 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS,
 KAM_LAZY_DOMAIN_SECURITY, KAM_SHORT, SPF_HELO_NONE, SPF_NONE,
 TXREP autolearn=no autolearn_force=no version=3.4.2
X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on
 server2.sourceware.org
X-BeenThere: fortran@gcc.gnu.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Fortran mailing list <fortran.gcc.gnu.org>
List-Unsubscribe: <https://gcc.gnu.org/mailman/options/fortran>,
 <mailto:fortran-request@gcc.gnu.org?subject=unsubscribe>
List-Archive: <https://gcc.gnu.org/pipermail/fortran/>
List-Help: <mailto:fortran-request@gcc.gnu.org?subject=help>
List-Subscribe: <https://gcc.gnu.org/mailman/listinfo/fortran>,
 <mailto:fortran-request@gcc.gnu.org?subject=subscribe>
X-List-Received-Date: Tue, 28 Jul 2020 15:58:19 -0000

This bug

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96325

should be a high priority for anyone trying to improve
gfortran.  Not only does gfortran accept an invalid 
Fortran program, the wrong code is simply bad.

Simplified testcase:

program bar 
   implicit none

   type t2
      integer r1
   end type

   type(t2) :: t
   integer :: a
   
   a = t%r1%foo(1)   ! There is no foo component/TBP.
   if (a == 42) stop
end

-fdump-tree-original gives

MAIN__ ()
{
  integer(kind=4) a;
  struct t2 t;

  a = 1;
  if (a == 42)
    {
      _gfortran_stop_string (0B, 0, 0);
    }
  L.1:;
}

and -fdump-parse-tree shows

Namespace: A-Z: (UNKNOWN 0)
procedure name = bar
  symtree: 'T2'          || symbol: 't2'           
    type spec : (UNKNOWN 0)
    attributes: (DERIVED )
    components: 
    (r1 (INTEGER 4) ())
    hash: 48537418
    Procedure bindings:
    Operator bindings:
  symtree: 'a'           || symbol: 'a'            
    type spec : (INTEGER 4)
    attributes: (VARIABLE )
  symtree: 'bar'         || symbol: 'bar'          
    type spec : (UNKNOWN 0)
    attributes: (PROGRAM PUBLIC  SUBROUTINE)
  symtree: 't'           || symbol: 't'            
    type spec : (DERIVED t2)
    attributes: (VARIABLE )
  symtree: 't2'          || symbol: 't2'           
    type spec : (UNKNOWN 0)
    attributes: (PROCEDURE  FUNCTION)
    Generic interfaces: t2

  code:
  ASSIGN bar:a 1
  IF (= bar:a 42)
    STOP -1
  ENDIF

I've run out of ideas on how to track this done.
Something in gfc_match_rvalue() goes sideways.

-- 
Steve