diff --git a/android/arch.go b/android/arch.go
index 606de48..61564d8 100644
--- a/android/arch.go
+++ b/android/arch.go
@@ -260,7 +260,7 @@
 	return target.Os.String() + "_" + target.Arch.String()
 }
 
-func ArchMutator(mctx BottomUpMutatorContext) {
+func archMutator(mctx BottomUpMutatorContext) {
 	var module Module
 	var ok bool
 	if module, ok = mctx.Module().(Module); !ok {