c41304a.ada

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-- C41304A.ADA

--                             Grant of Unlimited Rights
--
--     Under contracts F33600-87-D-0337, F33600-84-D-0280, MDA903-79-C-0687,
--     F08630-91-C-0015, and DCA100-97-D-0025, the U.S. Government obtained 
--     unlimited rights in the software and documentation contained herein.
--     Unlimited rights are defined in DFAR 252.227-7013(a)(19).  By making 
--     this public release, the Government intends to confer upon all 
--     recipients unlimited rights  equal to those held by the Government.  
--     These rights include rights to use, duplicate, release or disclose the 
--     released technical data and computer software in whole or in part, in 
--     any manner and for any purpose whatsoever, and to have or permit others 
--     to do so.
--
--                                    DISCLAIMER
--
--     ALL MATERIALS OR INFORMATION HEREIN RELEASED, MADE AVAILABLE OR
--     DISCLOSED ARE AS IS.  THE GOVERNMENT MAKES NO EXPRESS OR IMPLIED 
--     WARRANTY AS TO ANY MATTER WHATSOEVER, INCLUDING THE CONDITIONS OF THE
--     SOFTWARE, DOCUMENTATION OR OTHER INFORMATION RELEASED, MADE AVAILABLE 
--     OR DISCLOSED, OR THE OWNERSHIP, MERCHANTABILITY, OR FITNESS FOR A
--     PARTICULAR PURPOSE OF SAID MATERIAL.
--*
-- OBJECTIVE:
--     CHECK THAT L.R RAISES CONSTRAINT_ERROR WHEN:
--       L DENOTES AN ACCESS OBJECT HAVING THE VALUE NULL.
--       L IS A FUNCTION CALL DELIVERING THE ACCESS VALUE NULL.

-- HISTORY:
--     WKB 08/14/81
--     JRK 08/17/81
--     SPS 10/26/82
--     TBN 03/26/86  PUT THE NON-EXISTENT COMPONENT CASES INTO C41304B.
--     JET 01/05/88  MODIFIED HEADER FORMAT AND ADDED CODE TO PREVENT
--                   OPTIMIZATION.

WITH REPORT; USE REPORT;
PROCEDURE C41304A IS

     TYPE R IS
          RECORD
               I : INTEGER;
          END RECORD;

     TYPE T IS ACCESS R;

BEGIN
     TEST ("C41304A", "CONSTRAINT_ERROR WHEN L IN L.R DENOTES A NULL " &
                      "ACCESS OBJECT OR A FUNCTION CALL DELIVERING " &
                      "NULL");

     --------------------------------------------------

     DECLARE

          A : T := NEW R' (I => 1);
          J : INTEGER;

     BEGIN

          IF EQUAL (4, 4) THEN
               A := NULL;
          END IF;

          J := A.I;
          FAILED ("CONSTRAINT_ERROR NOT RAISED FOR A NULL ACCESS " &
                  "OBJECT");

          IF EQUAL (J,J) THEN
               COMMENT ("NO EXCEPTION RAISED");
          END IF;

     EXCEPTION

          WHEN CONSTRAINT_ERROR =>
               NULL;
          WHEN OTHERS =>
               FAILED ("WRONG EXCEPTION RAISED FOR A NULL ACCESS " &
                       "OBJECT");

     END;

     --------------------------------------------------

     DECLARE

          J : INTEGER;

          FUNCTION F RETURN T IS
          BEGIN
               IF EQUAL (4, 4) THEN
                    RETURN NULL;
               END IF;
               RETURN NEW R' (I => 2);
          END F;

     BEGIN

          J := F.I;
          FAILED ("CONSTRAINT_ERROR NOT RAISED FOR A FUNCTION CALL " &
                  "DELIVERING A NULL ACCESS VALUE");

          IF EQUAL (J,J) THEN
               COMMENT ("NO EXCEPTION RAISED");
          END IF;

     EXCEPTION

          WHEN CONSTRAINT_ERROR =>
               NULL;
          WHEN OTHERS =>
               FAILED ("WRONG EXCEPTION RAISED FOR A FUNCTION CALL " &
                       "DELIVERING A NULL ACCESS VALUE");

     END;

     RESULT;
END C41304A;