mmm 编译的时候报R.java类重复错误怎么搞？

packages/apps/installback2/gen/com/smart/Installback/R.java:10: 类重复： com.smart.Installback.R
public final class R {
             ^
1 错误
69 警告
make: *** [out/target/common/obj/APPS/InstallActivity_intermediates/classes-full-debug.jar] 错误 41
make:离开目录“/home/dongr/android/android-master”