diff --git a/runtime/vm/intermediate_language.cc b/runtime/vm/intermediate_language.cc
index 832214bdde8..f7bc0062642 100644
--- a/runtime/vm/intermediate_language.cc
+++ b/runtime/vm/intermediate_language.cc
@@ -312,9 +312,12 @@ void Definition::ReplaceUsesWith(Definition* other) {
   }
   current->definition_ = other;
 
-  current->next_use_ = other->use_list();
-  other->use_list()->previous_use_ = current;
+  if (other->use_list() != NULL) {
+    current->next_use_ = other->use_list();
+    other->use_list()->previous_use_ = current;
+  }
   other->set_use_list(head);
+  set_use_list(NULL);
 }
 
 
diff --git a/runtime/vm/intermediate_language_test.cc b/runtime/vm/intermediate_language_test.cc
index 2f7d5ae5f31..fd941fd90a5 100644
--- a/runtime/vm/intermediate_language_test.cc
+++ b/runtime/vm/intermediate_language_test.cc
@@ -39,6 +39,12 @@ TEST_CASE(DefUseTests) {
   BindInstr* bind = new BindInstr(BindInstr::kUsed, use2);
   bind->RemoveInputUses();
   EXPECT(def1->use_list() == NULL);
+  // Test replacing with a definition without uses.
+  UseVal* use4 = new UseVal(def2);
+  def2->ReplaceUsesWith(def1);
+  EXPECT(def1->use_list() == use4);
+  EXPECT(def2->use_list() == NULL);
+  EXPECT(use4->definition() == def1);
 }
 
 }  // namespace dart