diff --git a/pcbnew/class_zone.h b/pcbnew/class_zone.h
index 7a3fa96984..769ff58dde 100644
--- a/pcbnew/class_zone.h
+++ b/pcbnew/class_zone.h
@@ -206,8 +206,10 @@ public:
     int GetSelectedCorner() const
     {
         // Transform relative indices to global index
-        int globalIndex;
-        m_Poly->GetGlobalIndex( *m_CornerSelection, globalIndex );
+        int globalIndex = -1;
+
+        if( m_CornerSelection )
+            m_Poly->GetGlobalIndex( *m_CornerSelection, globalIndex );
 
         return globalIndex;
     }