FIX: Warning A4057 When Using Local Variables (68873)

The information in this article applies to:

Microsoft Macro Assembler (MASM) 5.1

This article was previously published under Q68873

SYMPTOMS

If the code below assembled with Microsoft Macro Assembler (MASM) version 5.1, it produces the following error:

Warning A4057: illegal size for operand

This warning is falsely generated and does not occur with MASM version 5.1a.

The variable arg1, shown in the code below, is a local variable that is defined as a double word. The warning occurs when arg1 is used as a WORD PTR. This is acceptable and should not be flagged.

STATUS

Microsoft has confirmed this to be a problem in MASM version 5.1. This problem was corrected in version 5.1a.

MORE INFORMATION

Sample Code

; Assemble options needed: none

.MODEL small,c

.CODE

Begin PROC arg1:DWORD
    mov ax, WORD PTR arg1
    ret
Begin ENDP

END

Modification Type:	Major	Last Reviewed:	10/20/2003
Keywords:	kbfix KB68873