[libcxx-commits] [libcxx] 7e69bd9 - [libc++] Use __enable_if_t and is_integral in cstddef

[Nikolas Klauser via libcxx-commits]

Author: Nikolas Klauser
Date: 2022-05-29T12:05:02+02:00
New Revision: 7e69bd9bf00ece8ac63aab91f73673d0d731bc24

URL: https://github.com/llvm/llvm-project/commit/7e69bd9bf00ece8ac63aab91f73673d0d731bc24
DIFF: https://github.com/llvm/llvm-project/commit/7e69bd9bf00ece8ac63aab91f73673d0d731bc24.diff

LOG: [libc++] Use __enable_if_t and is_integral in cstddef

Reviewed By: ldionne, #libc

Spies: libcxx-commits

Differential Revision: https://reviews.llvm.org/D126469

Added: 
    

Modified: 
    libcxx/include/__type_traits/enable_if.h
    libcxx/include/cstddef

Removed: 
    


################################################################################
diff  --git a/libcxx/include/__type_traits/enable_if.h b/libcxx/include/__type_traits/enable_if.h
index d7ccd6fd0368..c5e8df45ea58 100644
--- a/libcxx/include/__type_traits/enable_if.h
+++ b/libcxx/include/__type_traits/enable_if.h
@@ -10,7 +10,6 @@
 #define _LIBCPP___TYPE_TRAITS_ENABLE_IF_H
 
 #include <__config>
-#include <cstddef>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header

diff  --git a/libcxx/include/cstddef b/libcxx/include/cstddef
index 2b0659ab8ee7..8daba076d7db 100644
--- a/libcxx/include/cstddef
+++ b/libcxx/include/cstddef
@@ -35,6 +35,8 @@ Types:
 
 #include <__assert> // all public C++ headers provide the assertion handler
 #include <__config>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/integral_constant.h>
 #include <__type_traits/is_integral.h>
 #include <stddef.h>
 #include <version>
@@ -60,11 +62,6 @@ namespace std  // purposefully not versioned
 {
 enum class byte : unsigned char {};
 
-
-template <bool> struct __enable_if_integral_imp {};
-template <> struct __enable_if_integral_imp<true> { using type = byte; };
-template <class _Tp> using _EnableByteOverload = typename __enable_if_integral_imp<__libcpp_is_integral<_Tp>::value>::type;
-
 constexpr byte  operator| (byte  __lhs, byte __rhs) noexcept
 {
     return static_cast<byte>(
@@ -105,6 +102,10 @@ constexpr byte  operator~ (byte __b) noexcept
         ~static_cast<unsigned int>(__b)
     ));
 }
+
+template <class _Tp>
+using _EnableByteOverload = __enable_if_t<is_integral<_Tp>::value, byte>;
+
 template <class _Integer>
   constexpr _EnableByteOverload<_Integer> &
   operator<<=(byte& __lhs, _Integer __shift) noexcept