diff --git a/README_build.md b/README_build.md
index a815d065ff662d50707f908c5fb713621347eecd..0735ce710568492cc32554bf9a0e7ed281d91724 100644
--- a/README_build.md
+++ b/README_build.md
@@ -17,3 +17,7 @@
 
     xmake
 
+tips:
+
+    xmake/toolchain.lua CROSS_COMPILE
+