double casts

[Dan Pop]

the register mix-up I was talking about can't happen. But when the
compiler is evaluating function calls, it doesn't necessarily "know" how
the return values of the functions will be used.

Of course it knows how the return value is going to be used, but it
doesn't know how the function *really* returns this value, it has to
believe the function declaration currently in scope (which may be implicit
in C89). And if you lie to the compiler...

Dan