FIX: A5114: Operand Size Does Not Match Segment Word Size

ID: Q35882

The information in this article applies to:

Microsoft Macro Assembler for MS-DOS, versions 5.0, 5.1, 5.1a
Microsoft Macro Assembler for OS/2, versions 5.1, 5.1a

SYMPTOMS

The Microsoft Macro Assembler (MASM) versions 5.0, 5.1, and 5.1a may generate the warning:

A5114: Operand size does not match segment word size

when using 32-bit operands in USE16 segments. The warning is only generated on push and pop instructions using an operand with the size other than the size of the segment. For example, using DWORD push in a USE16 segment or using a WORD push in a USE32 segment. The warning is not generated for any other use of 32-bit operands.

CAUSE

The warning message may have been added to aid the programmer trying to convert code from 16-bit segments to 32-bit segments. The warning message should only occur in 32-bit segments when 16-bit push/pop operands are given, and not in the converse situation.

STATUS

Microsoft has confirmed this to be a problem in MASM versions 5.0, 5.1, 5.1a. This problem was corrected in MASM version 6.0.

MORE INFORMATION

Sample Code


; Assemble options needed: /W2

.386

_TEXT16 SEGMENT WORD PUBLIC USE16 'CODE'
ASSUME cs:_TEXT16

start:
    push eax
    pop eax
    mov ax, 4C00h
    int 21h
_TEXT16 ENDS

_TEXT32 SEGMENT WORD PUBLIC USE32 'CODE'
ASSUME cs:_TEXT32
    push ax
    pop ax
    mov ax, 4C00h
    int 21h
_TEXT32 ENDS

END start

Additional query words: 5.00 5.10 5.10a

Keywords :
Version : :5.0,5.1,5.1a
Platform :
Issue type :