diff --git a/litecross/Makefile b/litecross/Makefile
index 0b5fcac..19b3017 100644
--- a/litecross/Makefile
+++ b/litecross/Makefile
@@ -16,6 +16,7 @@ MUSL_CONFIG = CC="$(XGCC)" LIBCC="../obj_toolchain/$(TARGET)/libgcc/libgcc.a" --
 -include config.mak
 
 MAKE += INFO_DEPS=
+MAKE += ac_cv_prog_lex_root=lex.yy.c
 
 FULL_TOOLCHAIN_CONFIG = $(TOOLCHAIN_CONFIG) \
 	--disable-werror \