diff --git a/core/config.mk b/core/config.mk
index 39c58da..ebe348e 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -500,6 +500,7 @@
 BISON_PKGDATADIR := $(PWD)/external/bison/data
 BISON := prebuilts/misc/$(BUILD_OS)-$(HOST_PREBUILT_ARCH)/bison/bison
 YACC := $(BISON) -d
+BISON_DATA := $(wildcard external/bison/data/* external/bison/data/*/*)
 
 YASM := prebuilts/misc/$(BUILD_OS)-$(HOST_PREBUILT_ARCH)/yasm/yasm