diff --git a/dexpreopt/config.go b/dexpreopt/config.go
index 7a74506..de3666a 100644
--- a/dexpreopt/config.go
+++ b/dexpreopt/config.go
@@ -159,7 +159,7 @@
 }
 
 func constructPath(ctx android.PathContext, path string) android.Path {
-	buildDirPrefix := ctx.Config().BuildDir() + "/"
+	buildDirPrefix := ctx.Config().SoongOutDir() + "/"
 	if path == "" {
 		return nil
 	} else if strings.HasPrefix(path, buildDirPrefix) {