Q27201: Passed Double-Precision Array Assigned Long Integer Hangs

Article: Q27201
Product(s): See article
Version(s): 4.00 4.00b
Operating System(s): MS-DOS
Keyword(s): ENDUSER | B_BasicCom buglist4.00 buglist4.00b fixlist4.50 | mspl13_basic
Last Modified: 22-JAN-1990

In the following program, a double-precision array is passed to a
subprogram where a long integer is inserted into that array. If
compiled with BC.EXE (without /D debug switch), your machine will stop
when the program is run. The same program runs correctly inside the
editor.

The workaround is to use the debug (/D) option when compiling with
BC.EXE.

Microsoft has confirmed this to be a problem in QuickBASIC Versions
4.00 and 4.00b, and Microsoft BASIC Compiler Versions 6.00 and 6.00b
(buglist6.00, buglist6.00b) for MS-DOS and MS OS/2. This problem was
corrected in QuickBASIC Version 4.50 and in Microsoft BASIC
Professional Development System (PDS) Version 7.00 for MS-DOS and MS
OS/2 (fixlist7.00).

The following code is an example of this problem:

DECLARE SUB BFPPAC (A#(), i%)
                        'If put in $DYNAMIC OR $STATIC, it will work.
     DIM A#(4, 4)       'If it is a one-dimensional array, it will work.
     A#(1, 1) = 12345
     CALL BFPPAC(A#(), 3)   'If you pass only the array, it will work.
                          'CodeView says there is an illegal instruction
                          'here, and points to a POP statement in the
                          'assembly language version of the program.
     PRINT "THREE "
     FOR Z% = 1 TO 4        'If you do not print the array here, it
                            'will not hang, but when you print A#(1, 1)
           PRINT A#(Z%, 1)  'in the subprogram, it equals
     NEXT                   '2.316524914777163D-272 instead of 12345.
     END
SUB BFPPAC (A#(), i%) STATIC
     'w% = i%               'If you insert this line, it will work.
     M1& = A#(1, 1)
     PRINT "ONE", M1&, A#(1, 1)  'Always prints out correctly.
     A#(i%, 1) = M1&
     PRINT "TWO", M1&, A#(1, 1), A#(3, 1)
                                'M1& and A#(3,1) always print correctly,
                        'but if you have the program so it will
                    'hang, A#(1,1) will be
                                '9.058940453046392D-233 when it is printed
                                'out here.
END SUB

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.

Copyright Microsoft Corporation 1986-2002.