[gcc r13-432] libstdc++: Improve doxygen docs for some of <memory>

[gcc r13-432] libstdc++: Improve doxygen docs for some of <memory>

[Jonathan Wakely]

https://gcc.gnu.org/g:a278402216e75d5d54e62d2cd2345ea130349f10

commit r13-432-ga278402216e75d5d54e62d2cd2345ea130349f10
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Thu May 12 23:04:29 2022 +0100

    libstdc++: Improve doxygen docs for some of <memory>
    
    libstdc++-v3/ChangeLog:
    
            * doc/doxygen/user.cfg.in (PREDEFINED): Define
            _GLIBCXX23_CONSTEXPR macro.
            * include/backward/auto_ptr.h (auto_ptr): Use @deprecated.
            * include/bits/unique_ptr.h (default_delete): Use @since and
            @headerfile.
            * include/std/scoped_allocator: Remove @ingroup from @file
            block.

Diff:
---
 libstdc++-v3/doc/doxygen/user.cfg.in      |  1 +
 libstdc++-v3/include/backward/auto_ptr.h  |  4 ++++
 libstdc++-v3/include/bits/unique_ptr.h    | 13 ++++++++++---
 libstdc++-v3/include/std/scoped_allocator |  1 -
 4 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/libstdc++-v3/doc/doxygen/user.cfg.in b/libstdc++-v3/doc/doxygen/user.cfg.in
index cfda7ab13c4..4d21968cc57 100644
--- a/libstdc++-v3/doc/doxygen/user.cfg.in
+++ b/libstdc++-v3/doc/doxygen/user.cfg.in
@@ -2388,6 +2388,7 @@ PREDEFINED             = __cplusplus=202002L \
                          _GLIBCXX14_CONSTEXPR=constexpr \
                          _GLIBCXX17_CONSTEXPR=constexpr \
                          _GLIBCXX20_CONSTEXPR=constexpr \
+                         _GLIBCXX23_CONSTEXPR=constexpr \
                          "_GLIBCXX11_DEPRECATED= " \
                          "_GLIBCXX11_DEPRECATED_SUGGEST(E)= " \
                          "_GLIBCXX17_DEPRECATED= " \
diff --git a/libstdc++-v3/include/backward/auto_ptr.h b/libstdc++-v3/include/backward/auto_ptr.h
index 8725504d4c9..184ab403466 100644
--- a/libstdc++-v3/include/backward/auto_ptr.h
+++ b/libstdc++-v3/include/backward/auto_ptr.h
@@ -84,6 +84,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  _GLIBCXX_RESOLVE_LIB_DEFECTS
    *  127.  auto_ptr<> conversion issues
    *  These resolutions have all been incorporated.
+   *
+   * @headerfile memory
+   * @deprecated Deprecated in C++11, no longer in the standard since C++17.
+   * Use `unique_ptr` instead.
    */
   template<typename _Tp>
     class auto_ptr
diff --git a/libstdc++-v3/include/bits/unique_ptr.h b/libstdc++-v3/include/bits/unique_ptr.h
index ad60fada59b..e1ad7721a59 100644
--- a/libstdc++-v3/include/bits/unique_ptr.h
+++ b/libstdc++-v3/include/bits/unique_ptr.h
@@ -65,8 +65,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #pragma GCC diagnostic pop
 #endif
 
-  /// Primary template of default_delete, used by unique_ptr for single objects
-  /// @since C++11
+  /** Primary template of default_delete, used by unique_ptr for single objects
+   *
+   * @headerfile memory
+   * @since C++11
+   */
   template<typename _Tp>
     struct default_delete
     {
@@ -99,7 +102,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   // _GLIBCXX_RESOLVE_LIB_DEFECTS
   // DR 740 - omit specialization for array objects with a compile time length
 
-  /// Specialization of default_delete for arrays, used by `unique_ptr<T[]>`
+  /** Specialization of default_delete for arrays, used by `unique_ptr<T[]>`
+   *
+   * @headerfile memory
+   * @since C++11
+   */
   template<typename _Tp>
     struct default_delete<_Tp[]>
     {
diff --git a/libstdc++-v3/include/std/scoped_allocator b/libstdc++-v3/include/std/scoped_allocator
index f2e3ed9f783..c62b04874e2 100644
--- a/libstdc++-v3/include/std/scoped_allocator
+++ b/libstdc++-v3/include/std/scoped_allocator
@@ -24,7 +24,6 @@
 
 /** @file include/scoped_allocator
  *  This is a Standard C++ Library header.
- *  @ingroup allocators
  */
 
 #ifndef _SCOPED_ALLOCATOR