updated for version 7.4a.020
Problem:    Superfluous mb_ptr_adv().
Solution:   Remove the call. (Dominique Pelle)
diff --git a/src/regexp_nfa.c b/src/regexp_nfa.c
index b16ba56..02fe49e 100644
--- a/src/regexp_nfa.c
+++ b/src/regexp_nfa.c
@@ -1516,7 +1516,6 @@
 		    EMIT('-');
 		    EMIT(NFA_CONCAT);
 		}
-		mb_ptr_adv(regparse);
 
 		/* skip the trailing ] */
 		regparse = endp;
@@ -4582,7 +4581,7 @@
 
 	/* Go back the specified number of bytes, or as far as the
 	 * start of the previous line, to try matching "\@<=" or
-	 * not matching "\@<!". This is very ineffecient, limit the number of
+	 * not matching "\@<!". This is very inefficient, limit the number of
 	 * bytes if possible. */
 	if (state->val <= 0)
 	{