Index: src/GenPoly/ScopedMap.h
===================================================================
--- src/GenPoly/ScopedMap.h	(revision 927e9ce4ffe82f75b935217c518d2bbc146e885d)
+++ src/GenPoly/ScopedMap.h	(revision 6bc4734f7814e3b8c0b88cfe6548251fc5fc45e4)
@@ -90,5 +90,5 @@
 				return next_valid();
 			}
-			iterator& operator++ (int) { iterator tmp = *this; ++(*this); return tmp; }
+			iterator operator++ (int) { iterator tmp = *this; ++(*this); return tmp; }
 
 			iterator& operator-- () {
@@ -101,5 +101,5 @@
 				return prev_valid();
 			}
-			iterator& operator-- (int) { iterator tmp = *this; --(*this); return tmp; }
+			iterator operator-- (int) { iterator tmp = *this; --(*this); return tmp; }
 
 			bool operator== (const iterator &that) {
@@ -166,5 +166,5 @@
 				return next_valid();
 			}
-			const_iterator& operator++ (int) { const_iterator tmp = *this; ++(*this); return tmp; }
+			const_iterator operator++ (int) { const_iterator tmp = *this; ++(*this); return tmp; }
 
 			const_iterator& operator-- () {
@@ -177,5 +177,5 @@
 				return prev_valid();
 			}
-			const_iterator& operator-- (int) { const_iterator tmp = *this; --(*this); return tmp; }
+			const_iterator operator-- (int) { const_iterator tmp = *this; --(*this); return tmp; }
 
 			bool operator== (const const_iterator &that) {
Index: src/GenPoly/ScopedSet.h
===================================================================
--- src/GenPoly/ScopedSet.h	(revision 927e9ce4ffe82f75b935217c518d2bbc146e885d)
+++ src/GenPoly/ScopedSet.h	(revision 6bc4734f7814e3b8c0b88cfe6548251fc5fc45e4)
@@ -87,5 +87,5 @@
 				return next_valid();
 			}
-			iterator& operator++ (int) { iterator tmp = *this; ++(*this); return tmp; }
+			iterator operator++ (int) { iterator tmp = *this; ++(*this); return tmp; }
 
 			iterator& operator-- () {
@@ -98,5 +98,5 @@
 				return prev_valid();
 			}
-			iterator& operator-- (int) { iterator tmp = *this; --(*this); return tmp; }
+			iterator operator-- (int) { iterator tmp = *this; --(*this); return tmp; }
 
 			bool operator== (const iterator &that) {
@@ -163,5 +163,5 @@
 				return next_valid();
 			}
-			const_iterator& operator++ (int) { const_iterator tmp = *this; ++(*this); return tmp; }
+			const_iterator operator++ (int) { const_iterator tmp = *this; ++(*this); return tmp; }
 
 			const_iterator& operator-- () {
@@ -174,5 +174,5 @@
 				return prev_valid();
 			}
-			const_iterator& operator-- (int) { const_iterator tmp = *this; --(*this); return tmp; }
+			const_iterator operator-- (int) { const_iterator tmp = *this; --(*this); return tmp; }
 
 			bool operator== (const const_iterator &that) {