diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 60148b8..a54ea07 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -436,7 +436,7 @@ int			temp_file_limit = -1;
 
 int			num_temp_buffers = 1024;
 
-char	   *cluster_name = "";
+char	   *cluster_name;
 char	   *ConfigFileName;
 char	   *HbaFileName;
 char	   *IdentFileName;
@@ -3422,7 +3422,7 @@ static struct config_string ConfigureNamesString[] =
 			GUC_SUPERUSER_ONLY
 		},
 		&external_pid_file,
-		NULL,
+		"",
 		check_canonical_path, NULL, NULL
 	},
 
