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Q39439: DOCERR: SMSW, SGDT, SIDT, SLDT, VERR, VERW Don’t Assemble

Article: Q39439
Product(s): Microsoft Macro Assembler
Version(s): 5.0,5.1,5.1a
Operating System(s): 
Keyword(s): 
Last Modified: 06-MAY-2001

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The information in this article applies to:

- Microsoft Macro Assembler (MASM), versions 5.0, 5.1, 5.1a 
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SUMMARY
=======

The ".286" and ".386" operands do not allow the following to assemble:

  SMSW, SGDT, SIDT, SLDT, VERR, and VERW

One or two error messages are generated for each occurrence of these
instructions.

MORE INFORMATION
================

Page 412 (section 20.3) of the "Microsoft Macro Assembler Programmer's Guide" is
incorrect in saying that these instructions require "privileged mode." Also,
SMSW is spelled incorrectly (as "SMCW"). These instructions are allowed in all
modes; however, behavior may differ between real and protected modes.

The reference guide is also incorrect on several addressing points. See the Intel
"80286 and 80287 Programmer's Reference Manual" for more information.

The following is a sample program:

  ........................................................................
  ; The following program demonstrates :
  dosseg
  .286
  .model large
  .data
  table   dw 64 dup (?)
  .code
  start:
          SMSW ax
          SGDT table
          SIDT table
          SLDT ax
          VERR ax
          VERW ax

          end start

  ......................................................................

  C> masm test,,,;
  Microsoft (R) Macro Assembler Version 5.10
  Copyright (C) Microsoft Corp 1981, 1988.  All rights reserved.

  test.ASM(6): error A2105: Expected: instruction, directive, or label
  test.ASM(7): error A2105: Expected: instruction, directive, or label
  test.ASM(8): error A2105: Expected: instruction, directive, or label
  test.ASM(9): error A2105: Expected: instruction, directive, or label
  test.ASM(10): error A2105: Expected: instruction, directive, or label
  test.ASM(11): error A2105: Expected: instruction, directive, or label

    24002 Bytes symbol space free

        0 Warning Errors
        6 Severe  Errors
  .......................................................................

Additional query words: 5.00 5.10 5.10a

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM510 kbMASM500 kbMASM510a
Version           : :5.0,5.1,5.1a

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