DOCUMENT:Q76217  04-MAY-2001  [masm]
TITLE   :FIX: Nested Structures May Hang Macro Assembler 6.0
PRODUCT :Microsoft Macro Assembler
PROD/VER:MS-DOS:6.0
OPER/SYS:
KEYWORDS:

======================================================================
-------------------------------------------------------------------------------
The information in this article applies to:

 - Microsoft Macro Assembler (MASM), version 6.0 
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SYMPTOMS
========

Nested structures may cause the Microsoft Macro Assembler (MASM) version 6.0 to
hang when one structure contains a field of the type of another structure and it
is initialized. The code below demonstrates the problem more clearly.

RESOLUTION
==========

Pad the initializer to make it the size declared. In the sample code below,
padding the initializer for the member called People to three characters
corrects the problem.

STATUS
======

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

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

In the sample code, notice that the structure member Nme has a length of three
bytes. However, the structure called People initializes its Nme member to 'R',
which is one character instead of three. This produces the problem.

Under MS-DOS, the assembler logo will appear, and the system will hang. Under
OS/2, the following message appears:

   The process has stopped.
   The software diagnostic code (trap number) is 013.

Sample Code
-----------

   ; Assemble options needed: /c

   .MODEL small

   aStruct STRUCT
       Nme BYTE 3 DUP (?)
   aStruct ENDS

   bStruct STRUCT
       People aStruct <'R'>

   ; Replace above line with the following line to work around problem.
   ;
   ;   People aStruct <'R  '>    ; 'R' is followed by two spaces

   bStruct  ENDS

   .DATA
       Crash bStruct { }

   END

Additional query words: LOCK HANG STRUCT buglist6.00 fixlist6.00a

======================================================================
Keywords          :  
Technology        : kbMASMsearch kbAudDeveloper kbMASM600
Version           : MS-DOS:6.0
Solution Type     : kbfix

=============================================================================

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