FIX: Unary Minus and Mixed Complex*16 with Complex*8

• Microsoft FORTRAN PowerStation for MS-DOS, version 1.0

SYMPTOMS

Mixing COMPLEX*16 and COMPLEX*8 variables in an expression using the unary minus can give the wrong result.

RESOLUTION

Do not use a unary minus in a mixed COMPLEX expression. Make the minus a binary operator by subtracting the mixed COMPLEX expression from zero.

STATUS

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

MORE INFORMATION

FORTRAN PowerStation version 1.0 can be differentiated from the maintenance release version 1.0a by invoking the linker. Typing link32 | more from \F32\BIN directory will show version 2.8 for FORTRAN PowerStation version 1.0, and it will show version 1.0f for the maintenance release version 1.0a.

When the following sample code is run, the correct result will be displayed first:

Sample Code

C No compiler options required
        COMPLEX CVAR1,RESLT1,RESLT2
        COMPLEX*16 CVAR2
        CVAR1 = CMPLX(100,0)
        CVAR2 = DCMPLX(100,0)
        RESLT1 = 0 - CVAR1 * CVAR2   ! right result (binary -)
        RESLT2 =  - CVAR1 * CVAR2    ! wrong result (unary -)
        WRITE(*,*) RESLT1,RESLT2
        END 

Additional query words: 1.00 buglist1.00 fixlist1.00a

Keywords :
Version : :1.0
Platform :
Issue type :