[libc++][NFC] Use more appropriate type traits for a few cases

Author: philnik777

libcxx/include/__tuple/make_tuple_types.h

@@ -18,7 +18,7 @@
 #include <__tuple/tuple_size.h>
 #include <__tuple/tuple_types.h>
 #include <__type_traits/copy_cvref.h>
-#include <__type_traits/remove_cv.h>
+#include <__type_traits/remove_cvref.h>
 #include <__type_traits/remove_reference.h>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
@@ -58,7 +58,7 @@ template <class _Tp,
           bool _SameSize = (_Ep == tuple_size<__libcpp_remove_reference_t<_Tp> >::value)>
 struct __make_tuple_types {
   static_assert(_Sp <= _Ep, "__make_tuple_types input error");
-  using _RawTp = __remove_cv_t<__libcpp_remove_reference_t<_Tp> >;
+  using _RawTp = __remove_cvref_t<_Tp>;
   using _Maker = __make_tuple_types_flat<_RawTp, typename __make_tuple_indices<_Ep, _Sp>::type>;
   using type   = typename _Maker::template __apply_quals<_Tp>;
 };

libcxx/include/new

@@ -89,8 +89,7 @@ void  operator delete[](void* ptr, void*) noexcept;
 #include <__config>
 #include <__exception/exception.h>
 #include <__type_traits/is_function.h>
-#include <__type_traits/is_same.h>
-#include <__type_traits/remove_cv.h>
+#include <__type_traits/is_void.h>
 #include <__verbose_abort>
 #include <cstddef>
 #include <version>
@@ -342,7 +341,7 @@ inline _LIBCPP_HIDE_FROM_ABI void __libcpp_deallocate_unsized(void* __ptr, size_
 template <class _Tp>
 [[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp* __launder(_Tp* __p) _NOEXCEPT {
   static_assert(!(is_function<_Tp>::value), "can't launder functions");
-  static_assert(!(is_same<void, __remove_cv_t<_Tp> >::value), "can't launder cv-void");
+  static_assert(!is_void<_Tp>::value, "can't launder cv-void");
   return __builtin_launder(__p);
 }