Problem with #define'd macro...

[GORDON KEEGAN]

Attempting to compile the following (fragment, but displays the problem)
results in an 'invalid target for assignment' error on our VAX running
VMS 5.3-1, using VAX C 3.1-051.  It compiles fine if I remove the division
and multiplication.  Any insight posted or e-mailed would be greatly
appreciated.  (e-mail will be summarized...)


-----------------------  begin code fragment  -----------------------
#define DIV_MOD(d,r,x,y) ( y == 0.0 ? d = 0.0, r = x : d = x/y, r = x - d*y )

main()
{
float a,b;
float remainder;
float quotient;

a = 5, b = 2; DIV_MOD(quotient,remainder,a,b);
printf("DIV_MOD(%f,%f,%f,%f)\n", quotient, remainder, a, b);
}
-----------------------  end code fragment  -------------------------

aTdHvAaNnKcSe

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