v4.19.13 snapshot.
diff --git a/tools/lib/lockdep/Build b/tools/lib/lockdep/Build
new file mode 100644
index 0000000..6f66735
--- /dev/null
+++ b/tools/lib/lockdep/Build
@@ -0,0 +1 @@
+liblockdep-y += common.o lockdep.o preload.o rbtree.o