diff --git a/quic/core/quic_connection_id.cc b/quic/core/quic_connection_id.cc
index 7b4f41b..f446ac8 100644
--- a/quic/core/quic_connection_id.cc
+++ b/quic/core/quic_connection_id.cc
@@ -32,10 +32,10 @@
 // that they always land in the same hash bucket.
 class QuicConnectionIdHasher {
  public:
-  inline QuicConnectionIdHasher()
+  explicit inline QuicConnectionIdHasher()
       : QuicConnectionIdHasher(QuicRandom::GetInstance()) {}
 
-  inline QuicConnectionIdHasher(QuicRandom* random) {
+  explicit inline QuicConnectionIdHasher(QuicRandom* random) {
     random->RandBytes(&sip_hash_key_, sizeof(sip_hash_key_));
   }
 
diff --git a/quic/core/quic_connection_id_test.cc b/quic/core/quic_connection_id_test.cc
index 64afaf8..0d4b190 100644
--- a/quic/core/quic_connection_id_test.cc
+++ b/quic/core/quic_connection_id_test.cc
@@ -92,6 +92,12 @@
 
   // Verify that any two all-zero connection IDs of different lengths never
   // have the same hash.
+  if (sizeof(connection_id64_1.Hash()) < sizeof(uint64_t) &&
+      !GetQuicRestartFlag(quic_connection_id_use_siphash)) {
+    // The old hashing algorithm returns 0 for all-zero connection IDs on
+    // 32bit platforms.
+    return;
+  }
   const char connection_id_bytes[kQuicMaxConnectionIdLength] = {};
   for (uint8_t i = 0; i < kQuicMaxConnectionIdLength - 1; ++i) {
     QuicConnectionId connection_id_i(connection_id_bytes, i);