If grep searches for string specified in a bracket expression, then for some
UTF8 locales (ru_RU.UTF-8) grep does not print a match. For some locales
dfaparse sets the global flag hard_LC_COLLATE (dfa.c:1418) to denote that
characters are ordered in a strange way (e.g. Russian cyrilic). If
hard_LC_COLLATE is set, then lex prepares the info about the letters in the
bracket expression and finally calls in_coll_range (dfa.c:1103-1116). Now,
in_coll_range uses the correct function strcoll to compare the letters, but the
condition is incorrect and the wrong character are selected to be in the range
that is specified by the bracket expression. Hence, there is no match reported. 

Example of Correct Fix: 
Fix the simple operator fault. 

Examples of Incorrect Fixes: 
1) Fix locale, such that multibyte characters do not need to be handled
(Regression because LC_ALL is supposed to be handled). 

2) Implement in_coll_range as locale implemented match (Regression because
match is supposed to be locale dependent).