diff --git a/src/core/include/mp-units/ext/inplace_vector.h b/src/core/include/mp-units/ext/inplace_vector.h
index 58970e5f..02682bcd 100644
--- a/src/core/include/mp-units/ext/inplace_vector.h
+++ b/src/core/include/mp-units/ext/inplace_vector.h
@@ -128,7 +128,7 @@ public:
   }
 
 private:
-  T data_[N];
+  T data_[N] = {};
   size_type size_ = 0;
 };