Q69067: Even and Align Directives Are Ignored in Inline Assembly

Article: Q69067
Product(s): See article
Version(s): 2.00 2.01 2.50 2.51
Operating System(s): MS-DOS
Keyword(s): ENDUSER | s_c buglist2.00 buglist 2.01 buglist2.50 buglist2.51 | mspl13_c
Last Modified: 6-FEB-1991

The use of the align and even directives in inline assembly blocks in
QuickC should generate NOP instructions so that the code that follows
the directive will reside on the specified byte boundary. However,
these directives never generate any NOP instructions.

The quick compile (/qc) feature of C versions 6.00 and 6.00a also
performs incorrectly. The align and even directives will work properly
under C versions 6.00 and C 6.00a if the /qc option is not used.

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

void main (void)
  {
  _asm
    {
    even
    push ds
    even
    pop  ds
    }
  }

Microsoft has confirmed this to be a problem in QuickC versions 2.00,
2.01, 2.50, 2.51 and C versions 6.00, and 6.00a (buglist6.00 and
buglist6.00a). We are researching this problem and will post new
information here as it becomes available.

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