Re: performance bug of `wc -m`

[Kaz Kylheku (Coreutils)]

On 2018-05-16 17:13, Eric Fischer wrote:
> I also found wcwidth to be a bad performance bottleneck in my multibyte
> branch of coreutils. To fix the problem in my branch, I added a cache 
> of
> the widths returned for characters in the range from 0 to UCHAR_MAX 
> (which
> perhaps should also be widened to include a few other common 
> alphabets).
> The caching code is at the bottom of

In what situation are there printable characters in the range [0, 
UCHAR_MAX) that
have a width > 1?

The lowest-numbered Unicode character that requires two spaces is 
U+1100, I think.