_Complex and _Imaginary datatypes

[Robert Dewar]

> Do you have any numbers on how large this increase in complexity is?
> Without looking closely at the issue I suspect the increased complexity
> from this is quite small, especially when compared to other language
> additions in C99 like variable-length arrays.

I think it would actually make the compiler *more* complicated to have
type complex be in a library. You would still want the compiler to recognize
this type specially and generate efficient code knowing about the type, and
this might be more difficult, not less if the type is not integral to the
language. Yes, it might make a simple student-type compiler simpler, but
then such projects can omit complex in any case.