regex [X-Z] with non-ascii char returns different results from (X|Y|Z)

[David Bremner]

"yury.t" <tptlab at tuta.io> writes:

> Some regular expression returns incorrect results if the pattern
> contains multibyte characters in square brackets.  The following
> bracket expression matches subjects not starting with `[１-９]` and
> returns more results than the parenthesis expression.

We rely on POSIX.2 regex functions (regcomp, regexec). I would be
interested to know if the searches you are interested in work in a
standalone C program using regcomp and regexec.

d