diff --git a/src/libmain/loggers.cc b/src/libmain/loggers.cc
index 350f90266..c44bb6408 100644
--- a/src/libmain/loggers.cc
+++ b/src/libmain/loggers.cc
@@ -31,6 +31,8 @@ Logger * makeDefaultLogger() {
         return makeProgressBar();
     case LogFormat::barWithLogs:
         return makeProgressBar(true);
+    default:
+        abort();
     }
 }