Fix #204. #211
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Fix #204. #211
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The DFA handles word boundaries by tagging each state with an `is_word` flag that lets us determine whether the next byte in the haystack should cause a word boundary instruction to match. We were mishandling how this tagging happened for start states. In particular, the tag was not used as an index into the start state cache, and therefore could wind up choosing an incorrect but previously computed start state with the wrong flags set. This leads to incorrect matches. We fix this by using the right flags to generate an index.
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The DFA handles word boundaries by tagging each state with an
is_wordflag that lets us determine whether the next byte in the haystack should
cause a word boundary instruction to match. We were mishandling how this
tagging happened for start states. In particular, the tag was not used as
an index into the start state cache, and therefore could wind up choosing
an incorrect but previously computed start state with the wrong flags set.
This leads to incorrect matches.
We fix this by using the right flags to generate an index.