FIX: /Zm and $-Constant Produces A2075 in MASM 6.0 (79829)

The information in this article applies to:

Microsoft Macro Assembler (MASM) 6.0

This article was previously published under Q79829

SYMPTOMS

In the Microsoft Macro Assembler (MASM) version 6.0, the following error message may be produced

A2075: jump destination too far : by xxxxx byte(s)

when using the /Zm option, the MASM driver with MASM 6.0, or OPTION M510. When MASM 5.1 compatibility is not used or MASM 5.1 is used, the code assembles correctly.

CAUSE

This behavior is caused by using the current address operator, $, minus a constant (for example, jmp $-5), and the MASM driver with MASM 6.0, OPTION M510, or the /Zm switch when assembling.

RESOLUTION

Use a label instead of the current address operator or assemble without the MASM 5.1 switch.

STATUS

Microsoft has confirmed this to be a problem in MASM version 6.0. This problem was corrected in MASM version 6.0a.

MORE INFORMATION

The /Zm switch is the MASM 5.1 compatibility switch in MASM 6.0. The MASM driver calls ML with the /Zm option in MASM 6.0. OPTION M510 is a directive that specifies MASM 5.1 compatibility.

Sample Code

; Assembly options need: /Zm

DOSSEG
.MODEL small
.STACK 4096
.DATA
.CODE
start:  mov     al,5h
here:   dec     al
        jnz     $-2             ; This line causes the A2075 error.
        ;jnz    here            ; Uncomment this line and comment out
        mov     ax,4c00h        ; jnz $-2 to get the code to assemble
        int     21h             ; correctly.
END     start

Modification Type:	Major	Last Reviewed:	10/17/2003
Keywords:	kbfix KB79829