diff --git a/crypto/fipsmodule/entropy/jitter.cc.inc b/crypto/fipsmodule/entropy/jitter.cc.inc
index af9993b..19c7fbf 100644
--- a/crypto/fipsmodule/entropy/jitter.cc.inc
+++ b/crypto/fipsmodule/entropy/jitter.cc.inc
@@ -153,7 +153,7 @@
  private:
   bool initialized_ = false;
   T sub_sampler_;
-  uint64_t last_sample_;
+  uint64_t last_sample_ = 0;
 };
 
 template <typename U>