BUG: R6000 During Compile with /MW, FORTRAN 5.1

• Microsoft FORTRAN for MS-DOS, version 5.1
• Microsoft FORTRAN for OS/2, version 5.1

SYMPTOMS

When using the /MW option while compiling a program with Microsoft FORTRAN version 5.1, the following error may occur during pass two of the compiler:

   run-time error R6000
   - stack overflow

CAUSE

This is an optimization problem in pass two of the compiler. If a subprogram is fairly large and contains a lot of I/O statements, when compiling with the /MW option, pass two of the compiler may generate R6000 - stack overflow.

RESOLUTION

To eliminate the problem, disable optimization by including the /Od option during the compile. An alternative solution is to break up the program into different modules and compile separately.

STATUS

Microsoft has confirmed this to be a problem in Microsoft FORTRAN version 5.1 for MS-DOS and OS/2. We are researching this problem and will post new information here as it becomes available.