diff --git a/libstdc++-v3/doc/doxygen/doxygroups.cc b/libstdc++-v3/doc/doxygen/doxygroups.cc
index 27d4a5e20ba..00d945ceba0 100644
--- a/libstdc++-v3/doc/doxygen/doxygroups.cc
+++ b/libstdc++-v3/doc/doxygen/doxygroups.cc
@@ -164,6 +164,21 @@ summarized in <a href="tables.html">tables</a>.  */
  * and condition variables.
  */
 
+/**
+ * @defgroup variable_templates Variable Templates
+ * @ingroup metaprogramming
+ * @since C++17
+ *
+ * Each trait in `<type_traits>` that has a `value` static data member is
+ * also available as a variable template, using the same name with a `_v`
+ * suffix. For example, `std::is_integral_v<T>` is a `bool` constant with
+ * the same value as `std::is_integral<T>::value`.
+ *
+ * In some cases, using the variable template instead of the `::value` member
+ * avoids instantiating the class template for the trait. This gives the
+ * compiler less work to do and can make your code compile a little faster.
+ */
+
 /**
  * @defgroup experimental Technical Specifications
  *
diff --git a/libstdc++-v3/include/bits/binders.h b/libstdc++-v3/include/bits/binders.h
index 972471745bd..51dba4cb446 100644
--- a/libstdc++-v3/include/bits/binders.h
+++ b/libstdc++-v3/include/bits/binders.h
@@ -23,7 +23,7 @@
 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 // <http://www.gnu.org/licenses/>.
 
-/** @file include/bits/binder.h
+/** @file include/bits/binders.h
  *  This is an internal header file, included by other library headers.
  *  Do not attempt to use it directly. @headername{functional}
  */
diff --git a/libstdc++-v3/include/bits/formatfwd.h b/libstdc++-v3/include/bits/formatfwd.h
index d2dfb17492d..d28ca70b7d8 100644
--- a/libstdc++-v3/include/bits/formatfwd.h
+++ b/libstdc++-v3/include/bits/formatfwd.h
@@ -56,6 +56,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   // [format.formatter], formatter
   template<typename _Tp, typename _CharT = char> struct formatter;
 
+/// @cond undocumented
 namespace __format
 {
 #ifdef _GLIBCXX_USE_WCHAR_T
diff --git a/libstdc++-v3/include/bits/forward_list.h b/libstdc++-v3/include/bits/forward_list.h
index 025486646f3..7b333b3b0b6 100644
--- a/libstdc++-v3/include/bits/forward_list.h
+++ b/libstdc++-v3/include/bits/forward_list.h
@@ -1461,7 +1461,7 @@ namespace __fwdlist
        *
        *  This function will insert copies of the data in the range
        *  `[ __first, __last)` into the %forward_list after the
-       *  location specified by `__pos.
+       *  location specified by `__pos`.
        *
        *  This operation is linear in the number of elements inserted and
        *  does not invalidate iterators and references.
diff --git a/libstdc++-v3/include/bits/out_ptr.h b/libstdc++-v3/include/bits/out_ptr.h
index 48fe3475b2f..cc5a8a3adac 100644
--- a/libstdc++-v3/include/bits/out_ptr.h
+++ b/libstdc++-v3/include/bits/out_ptr.h
@@ -396,7 +396,7 @@ namespace __detail
   /**
    * @tparam _Pointer The type of pointer to convert to.
    * @param __s The pointer that should take ownership of the result.
-   * @param __args... Arguments to use when resetting the smart pointer.
+   * @param __args Pack of arguments to use when resetting the smart pointer.
    * @return A `std::out_ptr_t` referring to `__s`.
    * @since C++23
    * @headerfile <memory>
@@ -417,7 +417,7 @@ namespace __detail
   /**
    * @tparam _Pointer The type of pointer to convert to.
    * @param __s The pointer that should take ownership of the result.
-   * @param __args... Arguments to use when resetting the smart pointer.
+   * @param __args Pack of arguments to use when resetting the smart pointer.
    * @return A `std::inout_ptr_t` referring to `__s`.
    * @since C++23
    * @headerfile <memory>
diff --git a/libstdc++-v3/include/bits/regex_constants.h b/libstdc++-v3/include/bits/regex_constants.h
index 32b9de1000b..e18f162196e 100644
--- a/libstdc++-v3/include/bits/regex_constants.h
+++ b/libstdc++-v3/include/bits/regex_constants.h
@@ -335,9 +335,9 @@ namespace regex_constants
    * Format strings (from ECMA-262 [15.5.4.11]):
    * @li $$  The dollar-sign itself ($)
    * @li $&  The matched substring.
-   * @li $`  The portion of @a string that precedes the matched substring.
+   * @li $\`  The portion of the string that precedes the matched substring.
    *         This would be match_results::prefix().
-   * @li $'  The portion of @a string that follows the matched substring.
+   * @li $'  The portion of the string that follows the matched substring.
    *         This would be match_results::suffix().
    * @li $n  The nth capture, where n is in [1,9] and $n is not followed by a
    *         decimal digit.  If n <= match_results::size() and the nth capture
diff --git a/libstdc++-v3/include/bits/stl_map.h b/libstdc++-v3/include/bits/stl_map.h
index 1e119a95b5c..88a8faab924 100644
--- a/libstdc++-v3/include/bits/stl_map.h
+++ b/libstdc++-v3/include/bits/stl_map.h
@@ -1096,6 +1096,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        *  is assigned from __obj.
        *
        *  Insertion requires logarithmic time.
+       *  @{
        */
       template <typename _Obj>
 	pair<iterator, bool>
diff --git a/libstdc++-v3/include/bits/stl_pair.h b/libstdc++-v3/include/bits/stl_pair.h
index efe6f72569b..aa49f87fc13 100644
--- a/libstdc++-v3/include/bits/stl_pair.h
+++ b/libstdc++-v3/include/bits/stl_pair.h
@@ -101,9 +101,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   template<size_t...>
     struct _Index_tuple;
 
-  template<typename _Tp>
-    class complex;
-
   template<size_t _Int, class _Tp1, class _Tp2>
     constexpr typename tuple_element<_Int, pair<_Tp1, _Tp2>>::type&
     get(pair<_Tp1, _Tp2>& __in) noexcept;
@@ -153,6 +150,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     get(const array<_Tp, _Nm>&&) noexcept;
 
 #if __glibcxx_tuple_like >= 202311 // >= C++26
+  template<typename _Tp>
+    class complex;
+
   template<size_t _Int, typename _Tp>
     constexpr _Tp&
     get(complex<_Tp>&) noexcept;
@@ -233,8 +233,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       }
     };
 #endif // lib concepts
+  /// @endcond
 #endif // C++11
 
+  /// @cond undocumented
+
 #if __glibcxx_tuple_like // >= C++23
   template<typename _Tp>
     inline constexpr bool __is_tuple_v = false;
diff --git a/libstdc++-v3/include/bits/stl_set.h b/libstdc++-v3/include/bits/stl_set.h
index 14825cc05ac..ce35e28cde7 100644
--- a/libstdc++-v3/include/bits/stl_set.h
+++ b/libstdc++-v3/include/bits/stl_set.h
@@ -585,6 +585,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        *  to the first is returned.
        *
        *  Insertion requires logarithmic time (if the hint is not taken).
+       *  @{
        */
       iterator
       insert(const_iterator __position, const value_type& __x)
diff --git a/libstdc++-v3/include/std/functional b/libstdc++-v3/include/std/functional
index 314c0f6ac4a..91478d3e9fb 100644
--- a/libstdc++-v3/include/std/functional
+++ b/libstdc++-v3/include/std/functional
@@ -148,9 +148,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 #endif // __cpp_lib_invoke_r
 
+#if __cplusplus >= 201103L
   /// @cond undocumented
 
-#if __cplusplus >= 201103L
   template<typename _MemFunPtr,
 	   bool __is_mem_fn = is_member_function_pointer<_MemFunPtr>::value>
     class _Mem_fn_base
diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits
index a7f881fe973..bba7a3fd03d 100644
--- a/libstdc++-v3/include/std/type_traits
+++ b/libstdc++-v3/include/std/type_traits
@@ -2484,15 +2484,15 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     const size_t aligned_union<_Len, _Types...>::alignment_value;
 #pragma GCC diagnostic pop
 
-  /// @cond undocumented
-
+  // Decay trait for arrays and functions, used for perfect forwarding
+  // in make_pair, make_tuple, etc.
 #if _GLIBCXX_USE_BUILTIN_TRAIT(__decay)
   template<typename _Tp>
     struct decay
     { using type = __decay(_Tp); };
 #else
-  // Decay trait for arrays and functions, used for perfect forwarding
-  // in make_pair, make_tuple, etc.
+  /// @cond undocumented
+
   template<typename _Up>
     struct __decay_selector
     : __conditional_t<is_const<const _Up>::value, // false for functions
diff --git a/libstdc++-v3/libsupc++/exception b/libstdc++-v3/libsupc++/exception
index 0ae01be25dd..ab3e06da9f7 100644
--- a/libstdc++-v3/libsupc++/exception
+++ b/libstdc++-v3/libsupc++/exception
@@ -134,8 +134,8 @@ namespace std _GLIBCXX_VISIBILITY(default)
    *  stack unwinding [15.2].  end note]'
    *
    *  2: 'When `uncaught_exception()` is true, throwing an
-   *  %exception can result in a call of 1terminate()`
-   *  (15.5.1).'
+   *  %exception can result in a call of `terminate()`
+   *  (15.5.1).
    */
   _GLIBCXX17_DEPRECATED_SUGGEST("std::uncaught_exceptions()")
   bool uncaught_exception() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));