diff --git a/src/branch2.hpp b/src/branch2.hpp
index cf336c24..19b0a67f 100644
--- a/src/branch2.hpp
+++ b/src/branch2.hpp
@@ -20,6 +20,7 @@ public:
   Branch2(Branch2 &&);
   Branch2(toml::value const &);
   ~Branch2();
+  Branch2& operator=(Branch2 const &);
 
 public:
   bool enabled;