Index: llvm/include/llvm/ADT/IntrusiveRefCntPtr.h
===================================================================
--- llvm/include/llvm/ADT/IntrusiveRefCntPtr.h
+++ llvm/include/llvm/ADT/IntrusiveRefCntPtr.h
@@ -255,7 +255,7 @@
 }
 
 template <class T>
-bool operator==(std::nullptr_t A, const IntrusiveRefCntPtr<T> &B) {
+bool operator==(std::nullptr_t, const IntrusiveRefCntPtr<T> &B) {
   return !B;
 }
 
Index: llvm/include/llvm/Support/Error.h
===================================================================
--- llvm/include/llvm/Support/Error.h
+++ llvm/include/llvm/Support/Error.h
@@ -592,7 +592,7 @@
   }
 
   template <class T1, class T2>
-  static bool compareThisIfSameType(const T1 &a, const T2 &b) {
+  static bool compareThisIfSameType(const T1 &, const T2 &) {
     return false;
   }
 
Index: llvm/include/llvm/Support/FormatVariadicDetails.h
===================================================================
--- llvm/include/llvm/Support/FormatVariadicDetails.h
+++ llvm/include/llvm/Support/FormatVariadicDetails.h
@@ -48,7 +48,7 @@
   explicit stream_operator_format_adapter(T &&Item)
       : Item(std::forward<T>(Item)) {}
 
-  void format(llvm::raw_ostream &S, StringRef Options) override { S << Item; }
+  void format(llvm::raw_ostream &S, StringRef) override { S << Item; }
 };
 
 template <typename T> class missing_format_adapter;
@@ -153,7 +153,7 @@
 
 template <typename T>
 std::enable_if_t<uses_missing_provider<T>::value, missing_format_adapter<T>>
-build_format_adapter(T &&Item) {
+build_format_adapter(T &&) {
   return missing_format_adapter<T>();
 }
 }