fix buglets found by randomconfig

diff --git a/shell/ash.c b/shell/ash.c
index f7604cf..a5b19c8 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -12900,7 +12900,9 @@
 	INIT_G_misc();
 	INIT_G_memstack();
 	INIT_G_var();
+#if ENABLE_ASH_ALIAS
 	INIT_G_alias();
+#endif
 	INIT_G_cmdtable();
 
 #if PROFILE