diff --git a/llvm/include/llvm/ADT/BitVector.h b/llvm/include/llvm/ADT/BitVector.h
--- a/llvm/include/llvm/ADT/BitVector.h
+++ b/llvm/include/llvm/ADT/BitVector.h
@@ -29,7 +29,11 @@
 
 /// ForwardIterator for the bits that are set.
 /// Iterators get invalidated when resize / reserve is called.
-template <typename BitVectorT> class const_set_bits_iterator_impl {
+template <typename BitVectorT>
+class const_set_bits_iterator_impl
+    : public iterator_facade_base<const_set_bits_iterator_impl<BitVectorT>,
+                                  std::input_iterator_tag, unsigned,
+                                  std::ptrdiff_t, const unsigned *, unsigned> {
   const BitVectorT &Parent;
   int Current = 0;
 
@@ -43,7 +47,6 @@
       : Parent(Parent), Current(Current) {}
   explicit const_set_bits_iterator_impl(const BitVectorT &Parent)
       : const_set_bits_iterator_impl(Parent, Parent.find_first()) {}
-  const_set_bits_iterator_impl(const const_set_bits_iterator_impl &) = default;
 
   const_set_bits_iterator_impl operator++(int) {
     auto Prev = *this;