Index: libcxx/include/span
===================================================================
--- libcxx/include/span
+++ libcxx/include/span
@@ -329,13 +329,6 @@
     _LIBCPP_INLINE_VISIBILITY constexpr const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator(cend()); }
     _LIBCPP_INLINE_VISIBILITY constexpr const_reverse_iterator   crend() const noexcept { return const_reverse_iterator(cbegin()); }
 
-    _LIBCPP_INLINE_VISIBILITY constexpr void swap(span &__other) noexcept
-    {
-        pointer __p = __data;
-        __data = __other.__data;
-        __other.__data = __p;
-    }
-
     _LIBCPP_INLINE_VISIBILITY span<const byte, _Extent * sizeof(element_type)> __as_bytes() const noexcept
     { return {reinterpret_cast<const byte *>(data()), size_bytes()}; }
 
@@ -499,17 +492,6 @@
     _LIBCPP_INLINE_VISIBILITY constexpr const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator(cend()); }
     _LIBCPP_INLINE_VISIBILITY constexpr const_reverse_iterator   crend() const noexcept { return const_reverse_iterator(cbegin()); }
 
-    _LIBCPP_INLINE_VISIBILITY constexpr void swap(span &__other) noexcept
-    {
-        pointer __p = __data;
-        __data = __other.__data;
-        __other.__data = __p;
-
-        index_type __sz = __size;
-        __size = __other.__size;
-        __other.__size = __sz;
-    }
-
     _LIBCPP_INLINE_VISIBILITY span<const byte, dynamic_extent> __as_bytes() const noexcept
     { return {reinterpret_cast<const byte *>(data()), size_bytes()}; }
 
@@ -562,12 +544,6 @@
 -> enable_if_t<!is_const_v<_Tp>, decltype(__s.__as_writable_bytes())>
 { return __s.__as_writable_bytes(); }
 
-template <class _Tp, size_t _Extent>
-_LIBCPP_INLINE_VISIBILITY
-constexpr void swap(span<_Tp, _Extent> &__lhs, span<_Tp, _Extent> &__rhs) noexcept
-{ __lhs.swap(__rhs); }
-
-
 //  Deduction guides
 template<class _Tp, size_t _Sz>
     span(_Tp (&)[_Sz]) -> span<_Tp, _Sz>;