COLLATIONS ARE USED.

ISSUE :
-------
Code points of HALF WIDTH KATAKANA in SJIS/CP932 range from
A1 to DF. In function my_wildcmp_mb_bin_impl while comparing
such single byte code points, there is a code which compares
signed character with unsigned character. Because of this,
comparisons of two same code points representing a HALF
WIDTH KATAKANA character always fails.

Solution:
---------
A code point of HALF WIDTH KATAKANA at-least need 8 bits.
Promoting the variable from uchar to int will fix the issue.