dfa: fix a theoretical bug

* src/dfa.c (dfaexec_main): After searching for a match from
the initial state, set the previous state, S1, to 0.
So far, we have found no case in which this fix makes a difference.
See http://debbugs.gnu.org/18645

1 files changed, 1 insertions, 0 deletions

diff --git a/src/dfa.c b/src/dfa.c
index 2e619826..58a4b832 100644
--- a/src/dfa.c
+++ b/src/dfa.c
@@ -3388,6 +3388,7 @@ dfaexec_main (struct dfa *d, char const *begin, char *end,
             {
               while (t[*p] == 0)
                 p++;
+              s1 = 0;
               s = t[*p++];
             }