1 files changed, 4 insertions, 2 deletions
diff --git a/lib/Transforms/IPO/GlobalOpt.cpp b/lib/Transforms/IPO/GlobalOpt.cpp
index ae9d4ce11e0d..f277a51ae659 100644
--- a/lib/Transforms/IPO/GlobalOpt.cpp
+++ b/lib/Transforms/IPO/GlobalOpt.cpp
@@ -239,7 +239,7 @@ static bool CleanupConstantGlobalUsers(Value *V, Constant *Init,
   // we delete a constant array, we may also be holding pointer to one of its
   // elements (or an element of one of its elements if we're dealing with an
   // array of arrays) in the worklist.
-  SmallVector<WeakVH, 8> WorkList(V->user_begin(), V->user_end());
+  SmallVector<WeakTrackingVH, 8> WorkList(V->user_begin(), V->user_end());
   while (!WorkList.empty()) {
     Value *UV = WorkList.pop_back_val();
     if (!UV)
@@ -1792,7 +1792,9 @@ static void makeAllConstantUsesInstructions(Constant *C) {
       NewU->insertBefore(UI);
       UI->replaceUsesOfWith(U, NewU);
     }
-    U->dropAllReferences();
+    // We've replaced all the uses, so destroy the constant. (destroyConstant
+    // will update value handles and metadata.)
+    U->destroyConstant();
   }
 }