diff --git a/cc/ndk_sysroot.go b/cc/ndk_sysroot.go
index 04dce7b..144d91c 100644
--- a/cc/ndk_sysroot.go
+++ b/cc/ndk_sysroot.go
@@ -108,5 +108,6 @@
 		Rule:      android.Touch,
 		Outputs:   []string{getNdkSysrootTimestampFile(ctx).String()},
 		Implicits: installPaths,
+		Optional:  true,
 	})
 }