diff --git a/kernel/hashlib.h b/kernel/hashlib.h
index 9cf43da6ca5..47aba71a834 100644
--- a/kernel/hashlib.h
+++ b/kernel/hashlib.h
@@ -371,7 +371,7 @@ class dict
 	}
 
 public:
-	class const_iterator : public std::iterator<std::forward_iterator_tag, std::pair<K, T>>
+	class const_iterator
 	{
 		friend class dict;
 	protected:
@@ -379,6 +379,11 @@ class dict
 		int index;
 		const_iterator(const dict *ptr, int index) : ptr(ptr), index(index) { }
 	public:
+		typedef std::forward_iterator_tag iterator_category;
+		typedef std::pair<K, T> value_type;
+		typedef ptrdiff_t difference_type;
+		typedef std::pair<K, T>* pointer;
+		typedef std::pair<K, T>& reference;
 		const_iterator() { }
 		const_iterator operator++() { index--; return *this; }
 		const_iterator operator+=(int amt) { index -= amt; return *this; }
@@ -389,7 +394,7 @@ class dict
 		const std::pair<K, T> *operator->() const { return &ptr->entries[index].udata; }
 	};
 
-	class iterator : public std::iterator<std::forward_iterator_tag, std::pair<K, T>>
+	class iterator
 	{
 		friend class dict;
 	protected:
@@ -397,6 +402,11 @@ class dict
 		int index;
 		iterator(dict *ptr, int index) : ptr(ptr), index(index) { }
 	public:
+		typedef std::forward_iterator_tag iterator_category;
+		typedef std::pair<K, T> value_type;
+		typedef ptrdiff_t difference_type;
+		typedef std::pair<K, T>* pointer;
+		typedef std::pair<K, T>& reference;
 		iterator() { }
 		iterator operator++() { index--; return *this; }
 		iterator operator+=(int amt) { index -= amt; return *this; }
@@ -800,7 +810,7 @@ class pool
 	}
 
 public:
-	class const_iterator : public std::iterator<std::forward_iterator_tag, K>
+	class const_iterator
 	{
 		friend class pool;
 	protected:
@@ -808,6 +818,11 @@ class pool
 		int index;
 		const_iterator(const pool *ptr, int index) : ptr(ptr), index(index) { }
 	public:
+		typedef std::forward_iterator_tag iterator_category;
+		typedef K value_type;
+		typedef ptrdiff_t difference_type;
+		typedef K* pointer;
+		typedef K& reference;
 		const_iterator() { }
 		const_iterator operator++() { index--; return *this; }
 		bool operator==(const const_iterator &other) const { return index == other.index; }
@@ -816,7 +831,7 @@ class pool
 		const K *operator->() const { return &ptr->entries[index].udata; }
 	};
 
-	class iterator : public std::iterator<std::forward_iterator_tag, K>
+	class iterator
 	{
 		friend class pool;
 	protected:
@@ -824,6 +839,11 @@ class pool
 		int index;
 		iterator(pool *ptr, int index) : ptr(ptr), index(index) { }
 	public:
+		typedef std::forward_iterator_tag iterator_category;
+		typedef K value_type;
+		typedef ptrdiff_t difference_type;
+		typedef K* pointer;
+		typedef K& reference;
 		iterator() { }
 		iterator operator++() { index--; return *this; }
 		bool operator==(const iterator &other) const { return index == other.index; }
@@ -1021,7 +1041,7 @@ class idict
 	pool<K, OPS> database;
 
 public:
-	class const_iterator : public std::iterator<std::forward_iterator_tag, K>
+	class const_iterator
 	{
 		friend class idict;
 	protected:
@@ -1029,6 +1049,11 @@ class idict
 		int index;
 		const_iterator(const idict &container, int index) : container(container), index(index) { }
 	public:
+		typedef std::forward_iterator_tag iterator_category;
+		typedef K value_type;
+		typedef ptrdiff_t difference_type;
+		typedef K* pointer;
+		typedef K& reference;
 		const_iterator() { }
 		const_iterator operator++() { index++; return *this; }
 		bool operator==(const const_iterator &other) const { return index == other.index; }
diff --git a/kernel/rtlil.h b/kernel/rtlil.h
index 17853fae163..d419872c66a 100644
--- a/kernel/rtlil.h
+++ b/kernel/rtlil.h
@@ -803,8 +803,14 @@ struct RTLIL::SigBit
 	unsigned int hash() const;
 };
 
-struct RTLIL::SigSpecIterator : public std::iterator<std::input_iterator_tag, RTLIL::SigSpec>
+struct RTLIL::SigSpecIterator
 {
+	typedef std::input_iterator_tag iterator_category;
+	typedef RTLIL::SigBit value_type;
+	typedef ptrdiff_t difference_type;
+	typedef RTLIL::SigBit* pointer;
+	typedef RTLIL::SigBit& reference;
+
 	RTLIL::SigSpec *sig_p;
 	int index;
 
@@ -814,8 +820,14 @@ struct RTLIL::SigSpecIterator : public std::iterator<std::input_iterator_tag, RT
 	inline void operator++() { index++; }
 };
 
-struct RTLIL::SigSpecConstIterator : public std::iterator<std::input_iterator_tag, RTLIL::SigSpec>
+struct RTLIL::SigSpecConstIterator
 {
+	typedef std::input_iterator_tag iterator_category;
+	typedef RTLIL::SigBit value_type;
+	typedef ptrdiff_t difference_type;
+	typedef RTLIL::SigBit* pointer;
+	typedef RTLIL::SigBit& reference;
+
 	const RTLIL::SigSpec *sig_p;
 	int index;