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Q66777: Formal Parameter Cannot Be Based on Previous Formal Parameter

Article: Q66777
Product(s): See article
Version(s): 6.00 6.00a | 6.00 6.00a
Operating System(s): MS-DOS | OS/2
Keyword(s): ENDUSER | S_QUICKC buglist6.00 buglist6.00a | mspl13_c
Last Modified: 26-NOV-1990

Based pointers and variables are introduced in Microsoft C version
6.00. One limitation of based addressing is that a formal parameter to
a function cannot be based on a previous formal parameter to the same
function. For example, the compiler will generate an error for the
following function definition, which has two formal parameters with
the second parameter based on the first:

   void foo( _segment myseg, int _based(myseg) *bptr )
   {
   }

The first parameter (myseg) is of type segment, while the second is a
based pointer to an integer (bptr) that is based on the myseg. If
these same variable declarations are not part of a formal parameter
list, they will compile without problem, but the above function will
generate the following compiler error for the based variable:

   error C2065: 'myseg' : undefined

Microsoft has confirmed this to be a problem in C versions 6.00 and
6.00a and QuickC versions 2.50 and 2.51 (buglist2.50 and buglist2.51).
We are researching this problem and will post new information here as
it becomes available.

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