diff --git a/steps/bison-3.4.1/mk/main.mk b/steps/bison-3.4.1/mk/main.mk
index 0f36d956..931c98c8 100644
--- a/steps/bison-3.4.1/mk/main.mk
+++ b/steps/bison-3.4.1/mk/main.mk
@@ -15,7 +15,7 @@ bison: src.a lib.a
 %.a: FORCE
 	set -e ;\
 	DIR=$(basename $@ .a) ;\
-	$(MAKE) CC=$(CC) AR=$(AR) CFLAGS=$(CGLAGS) -C $$DIR $@ ;\
+	$(MAKE) CC=$(CC) AR=$(AR) CFLAGS=$(CFLAGS) -C $$DIR $@ ;\
 	cp $$DIR/$@ $@
 
 FORCE: