diff --git a/make/generate-flex-bison.mk b/make/generate-flex-bison.mk
index 246b0a9..6f3f20c 100644
--- a/make/generate-flex-bison.mk
+++ b/make/generate-flex-bison.mk
@@ -64,7 +64,7 @@ $(FB_NAME)-dense.ebnf: $(GRAMMAR_INPUT) $(GENERATE_PY)
 	mv $@.tmp $@
 
 define generate_rule
-$(1): $$(GRAMMAR_INPUT) $$(GENERATE_PY) Makefile
+$(1): $$(GRAMMAR_INPUT) $$(GENERATE_PY) Makefile $(GENERATE_CONFIG_FILE)
 	$$(GENERATE) $$< $$(patsubst $(FB_NAME).%,$(FB_NAME).%,$$@) > $$@.tmp
 	mv $$@.tmp $$@
 endef