Implement C++17 <variant>. Patch from Michael Park!

This patch was reviewed as https://reviews.llvm.org/D23263.

llvm-svn: 288547

12 files changed, 78 insertions, 78 deletions

diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.assign/T.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.assign/T.pass.cpp
index 0a1d3c9e028..10022b14aa0 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.assign/T.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.assign/T.pass.cpp
@@ -116,7 +116,7 @@ void test_T_assignment_sfinae() {
     static_assert(!std::is_assignable<V, int>::value, "ambiguous");
   }
   {
-    using V = std::variant<int, int const &>;
+    using V = std::variant<int, const int &>;
     static_assert(!std::is_assignable<V, int>::value, "ambiguous");
   }
 #endif
@@ -149,9 +149,9 @@ void test_T_assignment_basic() {
     v = std::move(x);
     assert(v.index() == 1);
     assert(&std::get<1>(v) == &x);
-    // 'long' is selected by FUN(int const&) since 'int const&' cannot bind
+    // 'long' is selected by FUN(const int &) since 'const int &' cannot bind
     // to 'int&'.
-    int const &cx = x;
+    const int &cx = x;
     v = cx;
     assert(v.index() == 2);
     assert(std::get<2>(v) == 42);
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.assign/copy.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.assign/copy.pass.cpp
index 65c2052fdfe..0e1a0cd2a38 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.assign/copy.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.assign/copy.pass.cpp
@@ -24,32 +24,32 @@
 #include "test_macros.h"
 
 struct NoCopy {
-  NoCopy(NoCopy const &) = delete;
-  NoCopy &operator=(NoCopy const &) = default;
+  NoCopy(const NoCopy &) = delete;
+  NoCopy &operator=(const NoCopy &) = default;
 };
 
 struct NothrowCopy {
-  NothrowCopy(NothrowCopy const &) noexcept = default;
-  NothrowCopy &operator=(NothrowCopy const &) noexcept = default;
+  NothrowCopy(const NothrowCopy &) noexcept = default;
+  NothrowCopy &operator=(const NothrowCopy &) noexcept = default;
 };
 
 struct CopyOnly {
-  CopyOnly(CopyOnly const &) = default;
+  CopyOnly(const CopyOnly &) = default;
   CopyOnly(CopyOnly &&) = delete;
-  CopyOnly &operator=(CopyOnly const &) = default;
+  CopyOnly &operator=(const CopyOnly &) = default;
   CopyOnly &operator=(CopyOnly &&) = delete;
 };
 
 struct MoveOnly {
-  MoveOnly(MoveOnly const &) = delete;
+  MoveOnly(const MoveOnly &) = delete;
   MoveOnly(MoveOnly &&) = default;
-  MoveOnly &operator=(MoveOnly const &) = default;
+  MoveOnly &operator=(const MoveOnly &) = default;
 };
 
 struct MoveOnlyNT {
-  MoveOnlyNT(MoveOnlyNT const &) = delete;
+  MoveOnlyNT(const MoveOnlyNT &) = delete;
   MoveOnlyNT(MoveOnlyNT &&) {}
-  MoveOnlyNT &operator=(MoveOnlyNT const &) = default;
+  MoveOnlyNT &operator=(const MoveOnlyNT &) = default;
 };
 
 struct CopyAssign {
@@ -62,7 +62,7 @@ struct CopyAssign {
     copy_construct = copy_assign = move_construct = move_assign = alive = 0;
   }
   CopyAssign(int v) : value(v) { ++alive; }
-  CopyAssign(CopyAssign const &o) : value(o.value) {
+  CopyAssign(const CopyAssign &o) : value(o.value) {
     ++alive;
     ++copy_construct;
   }
@@ -71,7 +71,7 @@ struct CopyAssign {
     ++alive;
     ++move_construct;
   }
-  CopyAssign &operator=(CopyAssign const &o) {
+  CopyAssign &operator=(const CopyAssign &o) {
     value = o.value;
     ++copy_assign;
     return *this;
@@ -93,27 +93,27 @@ int CopyAssign::move_construct = 0;
 int CopyAssign::move_assign = 0;
 
 struct CopyMaybeThrows {
-  CopyMaybeThrows(CopyMaybeThrows const &);
-  CopyMaybeThrows &operator=(CopyMaybeThrows const &);
+  CopyMaybeThrows(const CopyMaybeThrows &);
+  CopyMaybeThrows &operator=(const CopyMaybeThrows &);
 };
 struct CopyDoesThrow {
-  CopyDoesThrow(CopyDoesThrow const &) noexcept(false);
-  CopyDoesThrow &operator=(CopyDoesThrow const &) noexcept(false);
+  CopyDoesThrow(const CopyDoesThrow &) noexcept(false);
+  CopyDoesThrow &operator=(const CopyDoesThrow &) noexcept(false);
 };
 
 #ifndef TEST_HAS_NO_EXCEPTIONS
 struct CopyThrows {
   CopyThrows() = default;
-  CopyThrows(CopyThrows const &) { throw 42; }
-  CopyThrows &operator=(CopyThrows const &) { throw 42; }
+  CopyThrows(const CopyThrows &) { throw 42; }
+  CopyThrows &operator=(const CopyThrows &) { throw 42; }
 };
 
 struct MoveThrows {
   static int alive;
   MoveThrows() { ++alive; }
-  MoveThrows(MoveThrows const &) { ++alive; }
+  MoveThrows(const MoveThrows &) { ++alive; }
   MoveThrows(MoveThrows &&) { throw 42; }
-  MoveThrows &operator=(MoveThrows const &) { return *this; }
+  MoveThrows &operator=(const MoveThrows &) { return *this; }
   MoveThrows &operator=(MoveThrows &&) { throw 42; }
   ~MoveThrows() { --alive; }
 };
@@ -123,13 +123,13 @@ int MoveThrows::alive = 0;
 struct MakeEmptyT {
   static int alive;
   MakeEmptyT() { ++alive; }
-  MakeEmptyT(MakeEmptyT const &) {
+  MakeEmptyT(const MakeEmptyT &) {
     ++alive;
     // Don't throw from the copy constructor since variant's assignment
     // operator performs a copy before committing to the assignment.
   }
   MakeEmptyT(MakeEmptyT &&) { throw 42; }
-  MakeEmptyT &operator=(MakeEmptyT const &) { throw 42; }
+  MakeEmptyT &operator=(const MakeEmptyT &) { throw 42; }
   MakeEmptyT &operator=(MakeEmptyT &&) { throw 42; }
   ~MakeEmptyT() { --alive; }
 };
@@ -164,7 +164,7 @@ void test_copy_assignment_sfinae() {
     static_assert(std::is_copy_assignable<V>::value, "");
   }
   {
-    // variant only provides copy assignment when beth the copy and move
+    // variant only provides copy assignment when both the copy and move
     // constructors are well formed
     using V = std::variant<int, CopyOnly>;
     static_assert(!std::is_copy_assignable<V>::value, "");
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.assign/move.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.assign/move.pass.cpp
index 0e07d13e9e9..f3dc8155b6b 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.assign/move.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.assign/move.pass.cpp
@@ -26,36 +26,36 @@
 #include "variant_test_helpers.hpp"
 
 struct NoCopy {
-  NoCopy(NoCopy const &) = delete;
-  NoCopy &operator=(NoCopy const &) = default;
+  NoCopy(const NoCopy &) = delete;
+  NoCopy &operator=(const NoCopy &) = default;
 };
 
 struct CopyOnly {
-  CopyOnly(CopyOnly const &) = default;
+  CopyOnly(const CopyOnly &) = default;
   CopyOnly(CopyOnly &&) = delete;
-  CopyOnly &operator=(CopyOnly const &) = default;
+  CopyOnly &operator=(const CopyOnly &) = default;
   CopyOnly &operator=(CopyOnly &&) = delete;
 };
 
 struct MoveOnly {
-  MoveOnly(MoveOnly const &) = delete;
+  MoveOnly(const MoveOnly &) = delete;
   MoveOnly(MoveOnly &&) = default;
-  MoveOnly &operator=(MoveOnly const &) = delete;
+  MoveOnly &operator=(const MoveOnly &) = delete;
   MoveOnly &operator=(MoveOnly &&) = default;
 };
 
 struct MoveOnlyNT {
-  MoveOnlyNT(MoveOnlyNT const &) = delete;
+  MoveOnlyNT(const MoveOnlyNT &) = delete;
   MoveOnlyNT(MoveOnlyNT &&) {}
-  MoveOnlyNT &operator=(MoveOnlyNT const &) = delete;
+  MoveOnlyNT &operator=(const MoveOnlyNT &) = delete;
   MoveOnlyNT &operator=(MoveOnlyNT &&) = default;
 };
 
 struct MoveOnlyOddNothrow {
   MoveOnlyOddNothrow(MoveOnlyOddNothrow &&) noexcept(false) {}
-  MoveOnlyOddNothrow(MoveOnlyOddNothrow const &) = delete;
+  MoveOnlyOddNothrow(const MoveOnlyOddNothrow &) = delete;
   MoveOnlyOddNothrow &operator=(MoveOnlyOddNothrow &&) noexcept = default;
-  MoveOnlyOddNothrow &operator=(MoveOnlyOddNothrow const &) = delete;
+  MoveOnlyOddNothrow &operator=(const MoveOnlyOddNothrow &) = delete;
 };
 
 struct MoveAssignOnly {
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/T.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/T.pass.cpp
index b9ea61046b4..d33ea0bd3f4 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/T.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/T.pass.cpp
@@ -68,7 +68,7 @@ void test_T_ctor_sfinae() {
     static_assert(!std::is_constructible<V, int>::value, "ambiguous");
   }
   {
-    using V = std::variant<int, int const &>;
+    using V = std::variant<int, const int &>;
     static_assert(!std::is_constructible<V, int>::value, "ambiguous");
   }
 #endif
@@ -87,7 +87,7 @@ void test_T_ctor_basic() {
   }
 #if !defined(TEST_VARIANT_HAS_NO_REFERENCES)
   {
-    using V = std::variant<int const &, int &&, long>;
+    using V = std::variant<const int &, int &&, long>;
     static_assert(std::is_convertible<int &, V>::value, "must be implicit");
     int x = 42;
     V v(x);
@@ -95,7 +95,7 @@ void test_T_ctor_basic() {
     assert(&std::get<0>(v) == &x);
   }
   {
-    using V = std::variant<int const &, int &&, long>;
+    using V = std::variant<const int &, int &&, long>;
     static_assert(std::is_convertible<int, V>::value, "must be implicit");
     int x = 42;
     V v(std::move(x));
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/copy.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/copy.pass.cpp
index 78fab6258b4..18216c6da92 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/copy.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/copy.pass.cpp
@@ -24,22 +24,22 @@
 
 struct NonT {
   NonT(int v) : value(v) {}
-  NonT(NonT const &o) : value(o.value) {}
+  NonT(const NonT &o) : value(o.value) {}
   int value;
 };
 static_assert(!std::is_trivially_copy_constructible<NonT>::value, "");
 
 struct NoCopy {
-  NoCopy(NoCopy const &) = delete;
+  NoCopy(const NoCopy &) = delete;
 };
 
 struct MoveOnly {
-  MoveOnly(MoveOnly const &) = delete;
+  MoveOnly(const MoveOnly &) = delete;
   MoveOnly(MoveOnly &&) = default;
 };
 
 struct MoveOnlyNT {
-  MoveOnlyNT(MoveOnlyNT const &) = delete;
+  MoveOnlyNT(const MoveOnlyNT &) = delete;
   MoveOnlyNT(MoveOnlyNT &&) {}
 };
 
@@ -47,13 +47,13 @@ struct MoveOnlyNT {
 struct MakeEmptyT {
   static int alive;
   MakeEmptyT() { ++alive; }
-  MakeEmptyT(MakeEmptyT const &) {
+  MakeEmptyT(const MakeEmptyT &) {
     ++alive;
     // Don't throw from the copy constructor since variant's assignment
     // operator performs a copy before committing to the assignment.
   }
   MakeEmptyT(MakeEmptyT &&) { throw 42; }
-  MakeEmptyT &operator=(MakeEmptyT const &) { throw 42; }
+  MakeEmptyT &operator=(const MakeEmptyT &) { throw 42; }
   MakeEmptyT &operator=(MakeEmptyT &&) { throw 42; }
   ~MakeEmptyT() { --alive; }
 };
@@ -124,7 +124,7 @@ void test_copy_ctor_valueless_by_exception() {
   using V = std::variant<int, MakeEmptyT>;
   V v1;
   makeEmpty(v1);
-  V const &cv1 = v1;
+  const V &cv1 = v1;
   V v(cv1);
   assert(v.valueless_by_exception());
 #endif
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/default.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/default.pass.cpp
index 124260bfcbf..a4a86ff6c1c 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/default.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/default.pass.cpp
@@ -71,7 +71,7 @@ void test_default_ctor_throws() {
   try {
     V v;
     assert(false);
-  } catch (int const &ex) {
+  } catch (const int &ex) {
     assert(ex == 42);
   } catch (...) {
     assert(false);
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/move.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/move.pass.cpp
index 2a87f32ef9a..66f67fe8d3f 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/move.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.ctor/move.pass.cpp
@@ -28,20 +28,20 @@ struct ThrowsMove {
 };
 
 struct NoCopy {
-  NoCopy(NoCopy const &) = delete;
+  NoCopy(const NoCopy &) = delete;
 };
 
 struct MoveOnly {
   int value;
   MoveOnly(int v) : value(v) {}
-  MoveOnly(MoveOnly const &) = delete;
+  MoveOnly(const MoveOnly &) = delete;
   MoveOnly(MoveOnly &&) = default;
 };
 
 struct MoveOnlyNT {
   int value;
   MoveOnlyNT(int v) : value(v) {}
-  MoveOnlyNT(MoveOnlyNT const &) = delete;
+  MoveOnlyNT(const MoveOnlyNT &) = delete;
   MoveOnlyNT(MoveOnlyNT &&other) : value(other.value) { other.value = -1; }
 };
 
@@ -49,13 +49,13 @@ struct MoveOnlyNT {
 struct MakeEmptyT {
   static int alive;
   MakeEmptyT() { ++alive; }
-  MakeEmptyT(MakeEmptyT const &) {
+  MakeEmptyT(const MakeEmptyT &) {
     ++alive;
     // Don't throw from the copy constructor since variant's assignment
     // operator performs a copy before committing to the assignment.
   }
   MakeEmptyT(MakeEmptyT &&) { throw 42; }
-  MakeEmptyT &operator=(MakeEmptyT const &) { throw 42; }
+  MakeEmptyT &operator=(const MakeEmptyT &) { throw 42; }
   MakeEmptyT &operator=(MakeEmptyT &&) { throw 42; }
   ~MakeEmptyT() { --alive; }
 };
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.dtor/dtor.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.dtor/dtor.pass.cpp
index 8e36a8aa135..7299394ee7b 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.dtor/dtor.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.dtor/dtor.pass.cpp
@@ -39,7 +39,7 @@ int NonTDtor1::count = 0;
 static_assert(!std::is_trivially_destructible<NonTDtor1>::value, "");
 
 struct TDtor {
-  TDtor(TDtor const &) {} // non-trivial copy
+  TDtor(const TDtor &) {} // non-trivial copy
   ~TDtor() = default;
 };
 static_assert(!std::is_trivially_copy_constructible<TDtor>::value, "");
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_index_args.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_index_args.pass.cpp
index 4dae324e665..8f694cfd5ed 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_index_args.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_index_args.pass.cpp
@@ -58,14 +58,14 @@ void test_emplace_sfinae() {
   }
 #if !defined(TEST_VARIANT_HAS_NO_REFERENCES)
   {
-    using V = std::variant<int, int &, int const &, int &&, TestTypes::NoCtors>;
+    using V = std::variant<int, int &, const int &, int &&, TestTypes::NoCtors>;
     static_assert(emplace_exists<V, 0>(), "");
     static_assert(emplace_exists<V, 0, int>(), "");
     static_assert(emplace_exists<V, 0, long long>(), "");
     static_assert(!emplace_exists<V, 0, int, int>(), "too many args");
     static_assert(emplace_exists<V, 1, int &>(), "");
     static_assert(!emplace_exists<V, 1>(), "cannot default construct ref");
-    static_assert(!emplace_exists<V, 1, int const &>(), "cannot bind ref");
+    static_assert(!emplace_exists<V, 1, const int &>(), "cannot bind ref");
     static_assert(!emplace_exists<V, 1, int &&>(), "cannot bind ref");
     static_assert(emplace_exists<V, 2, int &>(), "");
     static_assert(emplace_exists<V, 2, const int &>(), "");
@@ -74,8 +74,8 @@ void test_emplace_sfinae() {
                   "not constructible from void*");
     static_assert(emplace_exists<V, 3, int>(), "");
     static_assert(!emplace_exists<V, 3, int &>(), "cannot bind ref");
-    static_assert(!emplace_exists<V, 3, int const &>(), "cannot bind ref");
-    static_assert(!emplace_exists<V, 3, int const &&>(), "cannot bind ref");
+    static_assert(!emplace_exists<V, 3, const int &>(), "cannot bind ref");
+    static_assert(!emplace_exists<V, 3, const int &&>(), "cannot bind ref");
     static_assert(!emplace_exists<V, 4>(), "no ctors");
   }
 #endif
@@ -106,7 +106,7 @@ void test_basic() {
   }
 #if !defined(TEST_VARIANT_HAS_NO_REFERENCES)
   {
-    using V = std::variant<int, long, int const &, int &&, TestTypes::NoCtors,
+    using V = std::variant<int, long, const int &, int &&, TestTypes::NoCtors,
                            std::string>;
     const int x = 100;
     int y = 42;
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_type_args.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_type_args.pass.cpp
index 53a030d082a..4ca2cc4803e 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_type_args.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.mod/emplace_type_args.pass.cpp
@@ -52,12 +52,12 @@ void test_emplace_sfinae() {
     static_assert(!emplace_exists<V, void *, int>(), "cannot construct");
     static_assert(emplace_exists<V, void *, int *>(), "");
     static_assert(!emplace_exists<V, void *, const int *>(), "");
-    static_assert(emplace_exists<V, void const *, const int *>(), "");
-    static_assert(emplace_exists<V, void const *, int *>(), "");
+    static_assert(emplace_exists<V, const void *, const int *>(), "");
+    static_assert(emplace_exists<V, const void *, int *>(), "");
     static_assert(!emplace_exists<V, TestTypes::NoCtors>(), "cannot construct");
   }
 #if !defined(TEST_VARIANT_HAS_NO_REFERENCES)
-  using V = std::variant<int, int &, int const &, int &&, long, long,
+  using V = std::variant<int, int &, const int &, int &&, long, long,
                          TestTypes::NoCtors>;
   static_assert(emplace_exists<V, int>(), "");
   static_assert(emplace_exists<V, int, int>(), "");
@@ -65,17 +65,17 @@ void test_emplace_sfinae() {
   static_assert(!emplace_exists<V, int, int, int>(), "too many args");
   static_assert(emplace_exists<V, int &, int &>(), "");
   static_assert(!emplace_exists<V, int &>(), "cannot default construct ref");
-  static_assert(!emplace_exists<V, int &, int const &>(), "cannot bind ref");
+  static_assert(!emplace_exists<V, int &, const int &>(), "cannot bind ref");
   static_assert(!emplace_exists<V, int &, int &&>(), "cannot bind ref");
-  static_assert(emplace_exists<V, int const &, int &>(), "");
-  static_assert(emplace_exists<V, int const &, const int &>(), "");
-  static_assert(emplace_exists<V, int const &, int &&>(), "");
-  static_assert(!emplace_exists<V, int const &, void *>(),
+  static_assert(emplace_exists<V, const int &, int &>(), "");
+  static_assert(emplace_exists<V, const int &, const int &>(), "");
+  static_assert(emplace_exists<V, const int &, int &&>(), "");
+  static_assert(!emplace_exists<V, const int &, void *>(),
                 "not constructible from void*");
   static_assert(emplace_exists<V, int &&, int>(), "");
   static_assert(!emplace_exists<V, int &&, int &>(), "cannot bind ref");
-  static_assert(!emplace_exists<V, int &&, int const &>(), "cannot bind ref");
-  static_assert(!emplace_exists<V, int &&, int const &&>(), "cannot bind ref");
+  static_assert(!emplace_exists<V, int &&, const int &>(), "cannot bind ref");
+  static_assert(!emplace_exists<V, int &&, const int &&>(), "cannot bind ref");
   static_assert(!emplace_exists<V, long, long>(), "ambiguous");
   static_assert(!emplace_exists<V, TestTypes::NoCtors>(),
                 "cannot construct void");
@@ -107,7 +107,7 @@ void test_basic() {
   }
 #if !defined(TEST_VARIANT_HAS_NO_REFERENCES)
   {
-    using V = std::variant<int, long, int const &, int &&, TestTypes::NoCtors,
+    using V = std::variant<int, long, const int &, int &&, TestTypes::NoCtors,
                            std::string>;
     const int x = 100;
     int y = 42;
@@ -117,8 +117,8 @@ void test_basic() {
     v.emplace<long>();
     assert(std::get<long>(v) == 0);
     // emplace a reference
-    v.emplace<int const &>(x);
-    assert(&std::get<int const &>(v) == &x);
+    v.emplace<const int &>(x);
+    assert(&std::get<const int &>(v) == &x);
     // emplace an rvalue reference
     v.emplace<int &&>(std::move(y));
     assert(&std::get<int &&>(v) == &y);
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.swap/swap.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.swap/swap.pass.cpp
index 1fb5c72e72f..416c6b4e334 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.swap/swap.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.swap/swap.pass.cpp
@@ -30,14 +30,14 @@ void swap(NotSwappable &, NotSwappable &) = delete;
 
 struct NotCopyable {
   NotCopyable() = default;
-  NotCopyable(NotCopyable const &) = delete;
-  NotCopyable &operator=(NotCopyable const &) = delete;
+  NotCopyable(const NotCopyable &) = delete;
+  NotCopyable &operator=(const NotCopyable &) = delete;
 };
 
 struct NotCopyableWithSwap {
   NotCopyableWithSwap() = default;
-  NotCopyableWithSwap(NotCopyableWithSwap const &) = delete;
-  NotCopyableWithSwap &operator=(NotCopyableWithSwap const &) = delete;
+  NotCopyableWithSwap(const NotCopyableWithSwap &) = delete;
+  NotCopyableWithSwap &operator=(const NotCopyableWithSwap &) = delete;
 };
 void swap(NotCopyableWithSwap &, NotCopyableWithSwap) {}
 
@@ -73,7 +73,7 @@ struct NothrowTypeImp {
   static void reset() { move_called = move_assign_called = swap_called = 0; }
   NothrowTypeImp() = default;
   explicit NothrowTypeImp(int v) : value(v) {}
-  NothrowTypeImp(NothrowTypeImp const &o) noexcept(NT_Copy) : value(o.value) {
+  NothrowTypeImp(const NothrowTypeImp &o) noexcept(NT_Copy) : value(o.value) {
     assert(false);
   } // never called by test
   NothrowTypeImp(NothrowTypeImp &&o) noexcept(NT_Move) : value(o.value) {
@@ -81,7 +81,7 @@ struct NothrowTypeImp {
     do_throw<!NT_Move>();
     o.value = -1;
   }
-  NothrowTypeImp &operator=(NothrowTypeImp const &) noexcept(NT_CopyAssign) {
+  NothrowTypeImp &operator=(const NothrowTypeImp &) noexcept(NT_CopyAssign) {
     assert(false);
     return *this;
   } // never called by the tests
diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant_reference.fail.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant_reference.fail.cpp
index 1e5b9271280..bda27f0e5eb 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant_reference.fail.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant_reference.fail.cpp
@@ -23,6 +23,6 @@ int main()
 {
     // expected-error@variant:* 3 {{static_assert failed}}
     std::variant<int, int&> v; // expected-note {{requested here}}
-    std::variant<int, int const&> v2; // expected-note {{requested here}}
+    std::variant<int, const int &> v2; // expected-note {{requested here}}
     std::variant<int, int&&> v3; // expected-note {{requested here}}
 }