diff --git a/kernel/rtlil.h b/kernel/rtlil.h
index 82cbfaf28..712250b3e 100644
--- a/kernel/rtlil.h
+++ b/kernel/rtlil.h
@@ -420,8 +420,12 @@ namespace RTLIL
 	// It maintains a reference counter that is used to make sure that the container is not modified while being iterated over.
 
 	template<typename T>
-	struct ObjIterator
-	{
+	struct ObjIterator {
+		using iterator_category = std::forward_iterator_tag;
+		using value_type = T;
+		using difference_type = ptrdiff_t;
+		using pointer = T*;
+		using reference = T&;
 		typename dict<RTLIL::IdString, T>::iterator it;
 		dict<RTLIL::IdString, T> *list_p;
 		int *refcount_p;
@@ -474,13 +478,25 @@ namespace RTLIL
 			return it != other.it;
 		}
 
-		inline void operator++() {
+
+		inline bool operator==(const RTLIL::ObjIterator<T> &other) const {
+			return !(*this != other);
+		}
+
+		inline ObjIterator<T>& operator++() {
 			log_assert(list_p != nullptr);
 			if (++it == list_p->end()) {
 				(*refcount_p)--;
 				list_p = nullptr;
 				refcount_p = nullptr;
 			}
+			return *this;
+		}
+
+		inline const ObjIterator<T> operator++(int) {
+			ObjIterator<T> result(*this);
+			++(*this);
+			return result;
 		}
 	};
 
diff --git a/kernel/yosys.h b/kernel/yosys.h
index c7b671724..84c797b2d 100644
--- a/kernel/yosys.h
+++ b/kernel/yosys.h
@@ -52,6 +52,7 @@
 #include <stdexcept>
 #include <memory>
 #include <cmath>
+#include <cstddef>
 
 #include <sstream>
 #include <fstream>