diff --git a/modules/dnn/include/opencv2/dnn/dnn.inl.hpp b/modules/dnn/include/opencv2/dnn/dnn.inl.hpp
index d6809ce3fd..8312a418f3 100644
--- a/modules/dnn/include/opencv2/dnn/dnn.inl.hpp
+++ b/modules/dnn/include/opencv2/dnn/dnn.inl.hpp
@@ -247,6 +247,7 @@ inline DictValue & DictValue::operator=(const DictValue &r)
 }
 
 inline DictValue::DictValue(const DictValue &r)
+    : pv(NULL)
 {
     type = r.type;
 
diff --git a/modules/gapi/include/opencv2/gapi/util/optional.hpp b/modules/gapi/include/opencv2/gapi/util/optional.hpp
index 1aa2b265d9..26d7b64a02 100644
--- a/modules/gapi/include/opencv2/gapi/util/optional.hpp
+++ b/modules/gapi/include/opencv2/gapi/util/optional.hpp
@@ -35,9 +35,9 @@ namespace util
         // instead {}
         optional() {};
         optional(const optional&) = default;
-        explicit optional(T &&value) noexcept;
-        explicit optional(const T &value) noexcept;
-        optional(optional &&) noexcept;
+        explicit optional(T&&) noexcept;
+        explicit optional(const T&) noexcept;
+        optional(optional&&) noexcept;
         // TODO: optional(nullopt_t) noexcept;
         // TODO: optional(const optional<U> &)
         // TODO: optional(optional<U> &&)
@@ -46,8 +46,8 @@ namespace util
         // TODO: optional(U&& value);
 
         // Assignment
-        optional& operator=(const optional& rhs) = default;
-        optional& operator=(optional&& rhs);
+        optional& operator=(const optional&) = default;
+        optional& operator=(optional&&);
 
         // Observers
         T* operator-> ();