--- mlton/Makefile.orig	2022-01-17 22:42:43 UTC
+++ mlton/Makefile
@@ -39,6 +39,8 @@ ifeq ($(RUN_MLTON_VERSION), $(firstword $(sort $(RUN_M
 RUN_MLTON_COMPILE_XARGS += -drop-pass zone
 else ifeq ($(RUN_MLTON_VERSION), $(firstword $(sort $(RUN_MLTON_VERSION) 20191003)))
 RUN_MLTON_COMPILE_XARGS += -disable-pass zone
+else
+RUN_MLTON_COMPILE_XARGS += -disable-pass zone
 endif
 
 FRONT_END_SOURCES :=		\