diff --git a/cpp/opaque-rust.cpp b/cpp/opaque-rust.cpp
index e4034e5..8a24bb9 100644
--- a/cpp/opaque-rust.cpp
+++ b/cpp/opaque-rust.cpp
@@ -340,7 +340,8 @@ typename Slice<T>::iterator::difference_type
 Slice<T>::iterator::operator-(const iterator &other) const noexcept {
   auto diff = std::distance(static_cast<char *>(other.pos),
                             static_cast<char *>(this->pos));
-  return diff / this->stride;
+  return diff / static_cast<typename Slice<T>::iterator::difference_type>(
+                    this->stride);
 }
 
 template <typename T>
diff --git a/cpp/opaque-rust.h b/cpp/opaque-rust.h
index 5d674da..14241a0 100644
--- a/cpp/opaque-rust.h
+++ b/cpp/opaque-rust.h
@@ -340,7 +340,8 @@ typename Slice<T>::iterator::difference_type
 Slice<T>::iterator::operator-(const iterator &other) const noexcept {
   auto diff = std::distance(static_cast<char *>(other.pos),
                             static_cast<char *>(this->pos));
-  return diff / this->stride;
+  return diff / static_cast<typename Slice<T>::iterator::difference_type>(
+                    this->stride);
 }
 
 template <typename T>