diff --git a/src/test/regress/pg_regress.c b/src/test/regress/pg_regress.c
index dda076847a3..f308da6c503 100644
--- a/src/test/regress/pg_regress.c
+++ b/src/test/regress/pg_regress.c
@@ -2182,6 +2182,17 @@ regression_main(int argc, char *argv[],
 		optind++;
 	}
 
+	/*
+	 * We must have a database to run the tests in; either a default name, or
+	 * one supplied by the --dbname switch.
+	 */
+	if (!(dblist && dblist->str && dblist->str[0]))
+	{
+		fprintf(stderr, _("%s: no database name was specified\n"),
+				progname);
+		exit(2);
+	}
+
 	if (config_auth_datadir)
 	{
 #ifdef ENABLE_SSPI