Article: Q35128
Product(s): Microsoft Macro Assembler
Version(s): 5.1,5.1a,6.0,6.0a,6.0b
Operating System(s):
Keyword(s):
Last Modified: 06-MAY-2001
-------------------------------------------------------------------------------
The information in this article applies to:
- Microsoft Macro Assembler (MASM), versions 5.1, 5.1a, 6.0, 6.0a, 6.0b
-------------------------------------------------------------------------------
SYMPTOMS
========
The example below will generate the warning:
warning A4016: Reserved word used as symbol: MOV
when assembled with Microsoft Macro Assembler (MASM) 5.1 and 5.1a. This warning
is misleading. MASM 6.0, 6.0a, and 6.0b generate the more specific error
message:
error A2001: immediate operand not allowed
CAUSE
=====
The reference to a_struc.a in the example below is a reference to a structure
template and not to a variable stored in memory. Thus, a_struc.a is a constant
or immediate operand. MASM 5.1 and 5.1a always looks up the second token on the
line first. In the case below, it sees "a_struc". Because a_struc is a structure
declaration, MASM assumes the line declares a structure instance with "MOV"
being the label. At this point, MASM errors on trying to use reserved symbol
"MOV" as a structure instance label.
RESOLUTION
==========
This is the expected behavior of MASM.
MORE INFORMATION
================
Sample Code
-----------
; Assemble options needed: none
a_struc STRUC
a DW ?
a_struc ENDS
_TEXT SEGMENT 'CODE'
ASSUME CS:_TEXT
start:
mov a_struc.a, ax
mov ax, 4C00h
int 21h
_TEXT ENDS
END start
Additional query words: 5.10 5.10a 6.00 6.00a 6.00b
======================================================================
Keywords :
Technology : kbMASMsearch kbAudDeveloper kbMASM510 kbMASM600 kbMASM600a kbMASM510a kbMASM600b
Version : :5.1,5.1a,6.0,6.0a,6.0b
=============================================================================