diff --git a/lib/CodeGen/MachineBlockPlacement.cpp b/lib/CodeGen/MachineBlockPlacement.cpp
index 412d0b1..304f167 100644
--- a/lib/CodeGen/MachineBlockPlacement.cpp
+++ b/lib/CodeGen/MachineBlockPlacement.cpp
@@ -766,6 +766,7 @@
   AlignLoops(F);
 
   BlockToChain.clear();
+  ChainAllocator.DestroyAll();
 
   // We always return true as we have no way to track whether the final order
   // differs from the original order.