diff --git a/llvm/include/llvm/ADT/ArrayRef.h b/llvm/include/llvm/ADT/ArrayRef.h
--- a/llvm/include/llvm/ADT/ArrayRef.h
+++ b/llvm/include/llvm/ADT/ArrayRef.h
@@ -290,6 +290,10 @@
     /// @}
   };
 
+  /// Explicitly support class template argument deduction.
+  template <typename T>
+  ArrayRef(const T &) -> ArrayRef<T>;
+
   /// MutableArrayRef - Represent a mutable reference to an array (0 or more
   /// elements consecutively in memory), i.e. a start pointer and a length.  It
   /// allows various APIs to take and modify consecutive elements easily and
@@ -444,6 +448,10 @@
     }
   };
 
+  /// Explicitly support class template argument deduction.
+  template <typename T>
+  MutableArrayRef(T &) -> MutableArrayRef<T>;
+
   /// This is a MutableArrayRef that owns its array.
   template <typename T> class OwningArrayRef : public MutableArrayRef<T> {
   public: