diff --git a/llvm/include/llvm/Support/FormatProviders.h b/llvm/include/llvm/Support/FormatProviders.h
--- a/llvm/include/llvm/Support/FormatProviders.h
+++ b/llvm/include/llvm/Support/FormatProviders.h
@@ -355,7 +355,6 @@
 
 template <typename IterT> class format_provider<llvm::iterator_range<IterT>> {
   using value = typename std::iterator_traits<IterT>::value_type;
-  using reference = typename std::iterator_traits<IterT>::reference;
 
   static StringRef consumeOneOption(StringRef &Style, char Indicator,
                                     StringRef Default) {
@@ -403,15 +402,13 @@
     auto Begin = V.begin();
     auto End = V.end();
     if (Begin != End) {
-      auto Adapter =
-          detail::build_format_adapter(std::forward<reference>(*Begin));
+      auto Adapter = detail::build_format_adapter(*Begin);
       Adapter.format(Stream, ArgStyle);
       ++Begin;
     }
     while (Begin != End) {
       Stream << Sep;
-      auto Adapter =
-          detail::build_format_adapter(std::forward<reference>(*Begin));
+      auto Adapter = detail::build_format_adapter(*Begin);
       Adapter.format(Stream, ArgStyle);
       ++Begin;
     }
diff --git a/llvm/include/llvm/Support/FormatVariadicDetails.h b/llvm/include/llvm/Support/FormatVariadicDetails.h
--- a/llvm/include/llvm/Support/FormatVariadicDetails.h
+++ b/llvm/include/llvm/Support/FormatVariadicDetails.h
@@ -75,8 +75,6 @@
 // Test if raw_ostream& << T -> raw_ostream& is findable via ADL.
 template <class T> class has_StreamOperator {
 public:
-  using ConstRefT = const std::decay_t<T> &;
-
   template <typename U>
   static char test(
       std::enable_if_t<std::is_same<decltype(std::declval<llvm::raw_ostream &>()
@@ -86,7 +84,8 @@
 
   template <typename U> static double test(...);
 
-  static bool const value = (sizeof(test<ConstRefT>(nullptr)) == 1);
+  // NOLINTNEXTLINE(readability-identifier-naming)
+  static bool const value = (sizeof(test<T>(nullptr)) == 1);
 };
 
 // Simple template that decides whether a type T should use the member-function
diff --git a/llvm/unittests/Support/FormatVariadicTest.cpp b/llvm/unittests/Support/FormatVariadicTest.cpp
--- a/llvm/unittests/Support/FormatVariadicTest.cpp
+++ b/llvm/unittests/Support/FormatVariadicTest.cpp
@@ -698,3 +698,49 @@
   EXPECT_EQ("X", formatv("{0}", fmt_consume(std::move(E1))).str());
   EXPECT_FALSE(E1.isA<StringError>()); // consumed
 }
+
+TEST(FormatVariadicTest, FormatFilterRange) {
+  std::vector<int> vec{0, 1, 2};
+  auto range = map_range(vec, [](int v) { return v + 1; });
+  EXPECT_EQ("1, 2, 3", formatv("{0}", range).str());
+}
+
+namespace {
+
+class IntegerValuesRange final
+    : public indexed_accessor_range<IntegerValuesRange, NoneType, int, int *,
+                                    int> {
+public:
+  using indexed_accessor_range<IntegerValuesRange, NoneType, int, int *,
+                               int>::indexed_accessor_range;
+
+  static int dereference(const NoneType &, ptrdiff_t index) {
+    return static_cast<int>(index);
+  }
+};
+
+TEST(FormatVariadicTest, FormatRangeNonRef) {
+  IntegerValuesRange range(None, 0, 3);
+  EXPECT_EQ("0, 1, 2",
+            formatv("{0}", make_range(range.begin(), range.end())).str());
+}
+
+class PassByRef {
+public:
+  int Val = 0;
+  PassByRef(int Val) : Val(Val) {}
+};
+
+raw_ostream &operator<<(raw_ostream &OS, PassByRef &Obj) {
+  return OS << Obj.Val;
+}
+
+static_assert(detail::has_StreamOperator<PassByRef &>::value, "");
+static_assert(detail::uses_stream_operator<PassByRef &>::value, "");
+
+TEST(FormatVariadicTest, StreamOperatorPassByRef) {
+  PassByRef Obj(10);
+  EXPECT_EQ("10", formatv("{0}", Obj).str());
+}
+
+} // namespace