FIX: $STORAGE:2 or /4I2 Generates Incorrect Code

The information in this article applies to:

• Microsoft FORTRAN PowerStation for MS-DOS, version 1.0

SYMPTOMS

Using the undocumented compiler option /4I2 or the equivalent undocumented metacommand $STORAGE:2 will:

• Miscalculate integer array sizes for DATA statements
• Interpret explicitly declared INTEGER*4 variables as INTEGER*2

RESOLUTION

The compiler option /4I2 and the metacommand $STORAGE:2 are not intended to be used with this compiler. They are not documented for the same reason. However, any erroneous behavior may be avoided by replacing every instance of "integer " with "integer*2 " and declaring

   implicit integer*2 (i-n)

It is necessary to replace every instance of "integer " with "integer*2 " because explicit integer declarations are treated as integer*4.

STATUS

Microsoft has confirmed this to be a problem in FORTRAN PowerStation for MS-DOS version 1.0. This problem has been resolved with FORTRAN PowerStation maintenance release version 1.0a for MS-DOS.

MORE INFORMATION

Sample Code 1

C Compile options needed: none (or comment out line 1 and use: /4I2) $storage:2

      integer iunit(3)
      data iunit/100,10,1/
      print*, iunit
      end

Sample Code 2

C Compile options needed: none (or comment out line 1 and use: /4I2) $storage:2

      integer*4 i,j
      j = 30000
      i = j*j
      print*, i,j
      end

C   -5888    30000

C   900000000    30000