Comment 2 for bug 1740426

> I've been in the habit of using '%lld' and '%zu' to print 'long long' and 'size_t' respectively.
> However, the windows world needs '%I64d' and '%Iu' instead.
> It would be nice to have compatibility macros for this.

I'm not sure I understand this comment. I have been using %lld and %llu on Windows. I believe I tested and %z is supported on VS2015 and up, but not on VS2010. But do we need to support VS2010 any more?