UCNs-in-IDs patch

[Per Bothner]

Per Bothner wrote:
> I think we have a requirement that
>   foo.c -> foo.E -> foo.s
> be the same as:
>   foo.c ->foo.s

To go further: it may be acceptable that foo.E always
be in UTF-8, even when that doesn't match the input Locale.
Or always use ASCII with \U-escapes.  Or better: if the
current locale uses UTF-8. emit UTF-8; otherwise emit
ASCII with \U-escapes.  Code that reads pre-processed input
should assume the input is UTF-8 which might contain \U-escapes,
rather than the current locale.

[I don't claim to know anything about the issues ...]
-- 
	--Per Bothner
per@bothner.com   http://per.bothner.com/