diff --git a/src/SimpleTree.h b/src/SimpleTree.h
index a4172e3..b098234 100644
--- a/src/SimpleTree.h
+++ b/src/SimpleTree.h
@@ -58,7 +58,7 @@ class SimpleTree {
         node_t* _high;
         signature_t(const SimpleTree::node_t&);
     } __attribute__((packed));
-    friend class ptrie::byte_iterator<signature_t>;
+    friend struct ptrie::byte_iterator<signature_t>;
 
     using nodemap_t = ptrie::map<signature_t,std::shared_ptr<node_t>>;
     SimpleTree() = default;
diff --git a/src/ZonotopStrategy.h b/src/ZonotopStrategy.h
index 2d15e1d..d5522ad 100644
--- a/src/ZonotopStrategy.h
+++ b/src/ZonotopStrategy.h
@@ -34,7 +34,6 @@
 
 class ZonotopStrategy {
 public:
-    ZonotopStrategy(const ZonotopStrategy& orig) = default;
     ZonotopStrategy(ZonotopStrategy&&) = default;
     virtual ~ZonotopStrategy() = default;
     ZonotopStrategy& operator=(ZonotopStrategy&&) = default;