diff --git a/src/interfaces/ecpg/preproc/ecpg.trailer b/src/interfaces/ecpg/preproc/ecpg.trailer
index 3b6d1e51924baca98c536d76fe3ef73bdfbd6c17..7e95b8da5eb8df696e4711b475ad1db07d68a339 100644
--- a/src/interfaces/ecpg/preproc/ecpg.trailer
+++ b/src/interfaces/ecpg/preproc/ecpg.trailer
@@ -90,7 +90,7 @@ connection_target: opt_database_name opt_server opt_port
 				strncmp($3 + strlen("//"), "127.0.0.1", strlen("127.0.0.1")) != 0)
 				mmerror(PARSE_ERROR, ET_ERROR, "Unix-domain sockets only work on \"localhost\" but not on \"%s\"", $3 + strlen("//"));
 
-			$$ = make3_str(make3_str(mm_strdup("\""), $1, mm_strdup(":")), $3, make3_str(make3_str($4, mm_strdup("/"), $6),	$7, mm_strdup("\"")));
+			$$ = make3_str(make3_str(mm_strdup("\""), $1, mm_strdup(":")), $3, make3_str(make3_str($4, mm_strdup("/"), $6), $7, mm_strdup("\"")));
 		}
 		| char_variable
 		{