diff --git a/llvm/include/llvm/CodeGen/MachineModuleInfo.h b/llvm/include/llvm/CodeGen/MachineModuleInfo.h
index c5c1889cf22a..b8e00395a475 100644
--- a/llvm/include/llvm/CodeGen/MachineModuleInfo.h
+++ b/llvm/include/llvm/CodeGen/MachineModuleInfo.h
@@ -144,11 +144,12 @@ class MachineModuleInfo {
   const Function *LastRequest = nullptr; ///< Used for shortcut/cache.
   MachineFunction *LastResult = nullptr; ///< Used for shortcut/cache.
 
+  MachineModuleInfo &operator=(MachineModuleInfo &&MMII) = delete;
+
 public:
   explicit MachineModuleInfo(const LLVMTargetMachine *TM = nullptr);
 
   MachineModuleInfo(MachineModuleInfo &&MMII);
-  MachineModuleInfo &operator=(MachineModuleInfo &&MMII) = default;
 
   ~MachineModuleInfo();