diff --git a/re2/dfa.cc b/re2/dfa.cc
index 1fc8a5a..43dddac 100644
--- a/re2/dfa.cc
+++ b/re2/dfa.cc
@@ -123,7 +123,7 @@ class DFA {
     uint32_t flag_;     // Empty string bitfield flags in effect on the way
                         // into this state, along with kFlagMatch if this
                         // is a matching state.
-    std::atomic<State*> next_[];    // Outgoing arrows from State,
+    std::atomic<State*> next_[0];    // Outgoing arrows from State,
                         // one per input byte class
   };