[gcc r11-10117] libstdc++: Remove unused functions in std::variant implementation

[Jonathan Wakely <redi@gcc.gnu.org>]

https://gcc.gnu.org/g:80056e27a6e8b3d00a74343bde931d583561ffe9

commit r11-10117-g80056e27a6e8b3d00a74343bde931d583561ffe9
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Fri Oct 15 11:52:08 2021 +0100

    libstdc++: Remove unused functions in std::variant implementation
    
    These functions aren't used, and accessing the storage as a void* isn't
    compatible with C++20 constexpr requirements anyway, so we're unlikely
    to ever start using them in future.
    
    libstdc++-v3/ChangeLog:
    
            * include/std/variant (_Variant_storage::_M_storage()): Remove.
            (__detail::__variant::__get_storage): Remove.
            (variant): Remove friend declaration of __get_storage.
    
    (cherry picked from commit 1ba7adabf29eb671e418692fad076ea6edd08e3d)

Diff:
---
 libstdc++-v3/include/std/variant | 23 -----------------------
 1 file changed, 23 deletions(-)

diff --git a/libstdc++-v3/include/std/variant b/libstdc++-v3/include/std/variant
index c0585cb5999..f101c426744 100644
--- a/libstdc++-v3/include/std/variant
+++ b/libstdc++-v3/include/std/variant
@@ -435,13 +435,6 @@ namespace __variant
       ~_Variant_storage()
       { _M_reset(); }
 
-      void*
-      _M_storage() const noexcept
-      {
-	return const_cast<void*>(static_cast<const void*>(
-	    std::addressof(_M_u)));
-      }
-
       constexpr bool
       _M_valid() const noexcept
       {
@@ -473,13 +466,6 @@ namespace __variant
       void _M_reset() noexcept
       { _M_index = static_cast<__index_type>(variant_npos); }
 
-      void*
-      _M_storage() const noexcept
-      {
-	return const_cast<void*>(static_cast<const void*>(
-	    std::addressof(_M_u)));
-      }
-
       constexpr bool
       _M_valid() const noexcept
       {
@@ -804,11 +790,6 @@ namespace __variant
     : _FUN_type<_Tp, _Variant>
     { };
 
-  // Returns the raw storage for __v.
-  template<typename _Variant>
-    void* __get_storage(_Variant&& __v) noexcept
-    { return __v._M_storage(); }
-
   template <typename _Maybe_variant_cookie, typename _Variant>
     struct _Extra_visit_slot_needed
     {
@@ -1685,10 +1666,6 @@ namespace __variant
 	friend constexpr decltype(auto)
 	__detail::__variant::__get(_Vp&& __v) noexcept;
 
-      template<typename _Vp>
-	friend void*
-	__detail::__variant::__get_storage(_Vp&& __v) noexcept;
-
 #define _VARIANT_RELATION_FUNCTION_TEMPLATE(__OP) \
       template<typename... _Tp> \
 	friend constexpr bool \