Q67612

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page	Q67612: Bad Code Generated for Function Returning _self Based Pointer	/pubs/pc/reference/microsoft/kb/Q67612/

Q67612: Bad Code Generated for Function Returning _self Based Pointer

Article: Q67612
Version(s): 6.00 6.00a | 6.00 6.00a
Operating System: MS-DOS     | OS/2
Flags: ENDUSER | buglist6.00 buglist6.00a
Last Modified: 30-JAN-1991

The C versions 6.00 and 6.00a compilers will generate incorrect code
for a function that returns a pointer based on self. The code
generated for the return statement introduces an extra level of
indirection.

Microsoft has confirmed this to be a problem in C versions 6.00 and
6.00a. We are researching this problem and will post new information
here as it becomes available.

The following program fragment demonstrates this problem. Compile the
code with the /Fc option to generate an assembly listing, and observe
the code in the resulting .COD file for the return statement in the
function test().

struct foo {
            int  _based((_segment) _self) *pbs;
           } far *pfoo;

int far *test(void)
{
   return(pfoo->pbs);
}