diff --git a/toonz/sources/common/tgeometry/tgeometry.cpp b/toonz/sources/common/tgeometry/tgeometry.cpp
index 609b0fd..5c2b704 100644
--- a/toonz/sources/common/tgeometry/tgeometry.cpp
+++ b/toonz/sources/common/tgeometry/tgeometry.cpp
@@ -368,6 +368,10 @@ TAffine4 TAffine4::rotationZ(double angle) {
 
 //==================================================================================================
 
+TAngleRangeSet::List::const_iterator TAngleRangeSet::Iterator::empty_iterator() {
+  static List list;
+  return list.end();
+}
 
 int TAngleRangeSet::find(Type a) const {
   assert(!m_angles.empty());
diff --git a/toonz/sources/include/tgeometry.h b/toonz/sources/include/tgeometry.h
index e40191c..80b7376 100644
--- a/toonz/sources/include/tgeometry.h
+++ b/toonz/sources/include/tgeometry.h
@@ -1367,6 +1367,8 @@ public:
     List::const_iterator m_current;
     bool m_lapped;
 
+    static List::const_iterator empty_iterator();
+
   public:
     inline Iterator(): m_flip(), m_lapped(true)
       { reset(); }
@@ -1377,7 +1379,7 @@ public:
 
     inline Iterator& set(bool full) {
       m_flip = full; m_lapped = !m_flip;
-      m_current = m_prebegin = m_begin = m_end = List::const_iterator();
+      m_current = m_prebegin = m_begin = m_end = empty_iterator();
       return *this;
     }