diff --git a/src/httpserver.cpp b/src/httpserver.cpp
index 3531039f744..6f84d5c83bd 100644
--- a/src/httpserver.cpp
+++ b/src/httpserver.cpp
@@ -198,9 +198,10 @@ std::string RequestMethodString(HTTPRequest::RequestMethod m)
         return "HEAD";
     case HTTPRequest::PUT:
         return "PUT";
-    default:
+    case HTTPRequest::UNKNOWN:
         return "unknown";
-    }
+    } // no default case, so the compiler can warn about missing cases
+    assert(false);
 }
 
 /** HTTP request callback */