diff --git a/lib/make/mb_build.mk b/lib/make/mb_build.mk
index 76d389f..988eaaf 100644
--- a/lib/make/mb_build.mk
+++ b/lib/make/mb_build.mk
@@ -2,6 +2,7 @@
 MB_BUILD_FLAG_CPU     ?= -mz80
 MB_BUILD_FLAG_LD      ?= --nostdinc
 MB_BUILD_SDASM_FLAGS  ?= -g -l -c -o
+MB_BUILD_SDCC_FLAGS   ?=
 MB_BUILD_SDAR_FLAGS   ?= -rc
 MB_BUILD_H2B_CMD      ?= $(PATH_HEX2BIN)/hex2bin
 MB_BUILD_SDCC_CMD     ?= $(PATH_SDCC)/sdcc
@@ -29,7 +30,7 @@ endef
 
 define mb_link_asm
 	@echo === Link asm module at $(3)
-	$(MB_BUILD_SDCC_CMD) $(MB_BUILD_FLAG_CPU) --no-std-crt0 --code-loc $(3) -o $(1) $(2)
+	$(MB_BUILD_SDCC_CMD) $(MB_BUILD_FLAG_CPU) $(MB_BUILD_SDCC_FLAGS) --no-std-crt0 --code-loc $(3) -o $(1) $(2)
 endef
 define mb_link_asm_0000
 	$(call mb_link_asm,$(1),$(2),0x0000)