FIX: Optimization Problem, $STORAGE:2 and Multiplication

ID: Q73392

The information in this article applies to:

Microsoft FORTRAN for MS-DOS, versions 5.0, 5.1
Microsoft FORTRAN for OS/2, versions 5.0, 5.1

SYMPTOMS

The sample code below produces the output:


  6     0

instead of the expected output


  6     1280

RESOLUTION

Use one of the following to work around the problem in the sample code:

Disable optimization by compiling with /Od

Delete $storage:2 so that the default $storage:4 is used

Assign the result of (iy - 1) in line 10 to a temporary variable and use the temporary variable in line 20.

STATUS

Microsoft has confirmed this to be a bug in the products listed above. This problem was corrected in FORTRAN PowerStation, version 1.0.

MORE INFORMATION

The following sample code can be used to demonstrate the problem.

Sample code


$storage:2
       call subs(6, 1)
       end

       subroutine subs(iy, ipage)
       integer bx, dx, tmp
10     bx = (ipage - 1) * 256
20     dx = (iy - 1) * 256
       write (*, *) iy, dx
       return
       end

Additional query words: 5.00 5.10 buglist5.00 buglist5.10 fixlist1.00

Keywords :
Version : :5.0,5.1
Platform :
Issue type :