diff -ur a/re2/re2/dfa.cc b/re2/re2/dfa.cc
--- a/re2/re2/dfa.cc	2022-04-22 19:08:28.597201892 +0000
+++ b/re2/re2/dfa.cc	2022-04-22 19:09:19.608577242 +0000
@@ -1734,7 +1734,7 @@
     return false;
   }
   if (params.start == DeadState)
-    return NULL;
+    return false;
   if (params.start == FullMatchState) {
     if (run_forward == want_earliest_match)
       *epp = text.begin();