Index: src/ResolvExpr/Occurs.cc
===================================================================
--- src/ResolvExpr/Occurs.cc	(revision 843054c23fcb725d2486e5e42e91b3741bc523b8)
+++ src/ResolvExpr/Occurs.cc	(revision 212c421ef409d6b6cfdc46f15d088a510a868f95)
@@ -14,10 +14,10 @@
 //
 
-#include <set>
-#include <algorithm>
-#include <iterator>
-#include "SynTree/Type.h"
-#include "SynTree/Visitor.h"
-#include "TypeEnvironment.h"
+#include <set>                // for set, _Rb_tree_const_iterator
+#include <string>             // for string
+
+#include "SynTree/Type.h"     // for TypeInstType, Type
+#include "SynTree/Visitor.h"  // for Visitor
+#include "TypeEnvironment.h"  // for EqvClass, TypeEnvironment
 
 namespace ResolvExpr {