FIX: FORTRAN 5.0 Loop Optimization, Subroutine, & Array Problem

The information in this article applies to:

• Microsoft FORTRAN for MS-DOS, version 5.0
• Microsoft FORTRAN for OS/2, version 5.0

SYMPTOMS

In FORTRAN version 5.0, the loop optimizer does not correctly optimize the subroutine MOVE in the code below, producing incorrect output.

RESOLUTION

Compiling with /Od or /Odt resolves the problem.

STATUS

Microsoft has confirmed this to be a problem in FORTRAN version 5.0. This problem was corrected in FORTRAN version 5.1.

MORE INFORMATION

Sample Code

      integer*2 buf(20)
      do 10 i=1,10

      call move(10,buf(11),buf)

      write(*,'(10(i8))') (buf(i),i=1,20)
      end

      Subroutine move(npts, y1, y2)
      integer*2 y1(*), y2(*)
      do 10 i=1,npts
        y2(i) = y1(i)

      return
      end

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