FIX: F1001 or Protection Violation, Structure Member Array I/O

The information in this article applies to:

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

SYMPTOMS

An attempt to compile an application in the OS/2 operating system fails and the third pass of the compiler generates a protection violation.

An attempt to compile the application in the MS-DOS operating system fails and the compiler generates the following messages:

   warning F4202: (subroutine name) : formal argument : never used

   fatal error F1001: Internal Compiler Error
   (compiler file '@(#)omf_ms.c:1.118', line 1093)
   Contact Microsoft Technical Support

CAUSE

The application passes a structure that contains an array to a subroutine. The subroutine specifies the entire structure element array (no subscript) in an I/O statement.

RESOLUTION

Use an implied-DO list to read or write the entire array.

STATUS

Microsoft has confirmed this to be a problem in FORTRAN version 5.0 for MS-DOS and OS/2. This problem was corrected in FORTRAN version 5.1 for MS-DOS and OS/2.

MORE INFORMATION

The following code example demonstrates this problem.

Sample Code #1

C Compile options needed: None

      STRUCTURE /T/
         INTEGER J(100)
      END STRUCTURE
      RECORD /T/ ST
      CALL SUB(ST)
      END

      SUBROUTINE SUB(ST)
        STRUCTURE /T/
          INTEGER J(100)
        END STRUCTURE
      RECORD /T/ ST
      WRITE(*, *) ST.J    ! Writes an entire array (no subscript).
      END

Sample Code #2

C Compile options needed: None

      STRUCTURE /T/
         INTEGER J(100)
      END STRUCTURE
      RECORD /T/ ST
      CALL SUB(ST)
      END

      SUBROUTINE SUB(ST)
        STRUCTURE /T/
          INTEGER J(100)
        END STRUCTURE
      RECORD /T/ ST
      WRITE(*,*) (ST.J(I), I = 1, 100) ! Uses an implied DO list.
      END