diff --git a/src/policy_cache.hpp b/src/policy_cache.hpp
index a9f0b881..c393d359 100644
--- a/src/policy_cache.hpp
+++ b/src/policy_cache.hpp
@@ -98,7 +98,7 @@ public:
   }
 
   const
-  char*
+  Key&
   find(std::string const &key_) const
   {
     uint64_t hash;