Problems with PR 21210

[Benjamin Kosnik]

> or that it leaves other 
> problems open in general, with respect to C99 complex vs. C++ complex?

I suspect this.

You're solving this issue just for std::complex. Admittedly the problem
domain may be small for this issue (although I suspect scientific
computing types would disagree). A solution may be useful for
more than just std::complex.

What happens if other C99 or C0x types are added (ie ucs2 integer
type)? I think figuring out a way to deal with this now in the general
case is probably a better idea.

Explicitly writing in conversion ctors for the builtin integer types
seems like a pretty big hack to me.

-benjamin