ID Number: Q30385
5.10 5.10A
MS-DOS
buglist5.10 buglist5.10a fixlist6.00
Summary:
The MOV instruction, using indirect addressing, and the Type
operator generate incorrect opcodes.
More Information:
The first MOV instruction generates the opcode "B8FFF4", which is a
move-immediate instruction. The assembler should generate the opcode
"8B44F4". This opcode is generated on the second move instruction.
MASM Version 5.00 generates the correct code for both MOV instructions.
The following code demonstrates the problem:
seg_1 segment para public 'code'
assume cs:seg_1
test_str struc
test_f1 dw ?
test_f2 dw ?
test_f3 db 8 dup (?)
test_str ends
main_entry proc
mov ax,word ptr [si] - type test_str
;
; This alternate generation works
;
mov ax,word ptr [ si - type test_str]
main_entry endp
seg_1 ends
end
Microsoft has confirmed this to be a problem in Microsoft Macro
Assembler versions 5.1 and 5.1a. This problem was corrected in MASM
version 6.0.
Additional reference words: 5.10 5.10a 6.00