libstdc++: Fix some -Wunused-parameter warnings

libstdc++-v3/ChangeLog:

	* include/bits/alloc_traits.h (allocate): Add [[maybe_unused]]
	attribute.
	* include/bits/regex_executor.tcc: Remove name of unused
	parameter.
	* include/bits/shared_ptr_atomic.h (atomic_is_lock_free):
	Likewise.
	* include/bits/stl_uninitialized.h: Likewise.
	* include/bits/streambuf_iterator.h (operator==): Likewise.
	* include/bits/uses_allocator.h: Likewise.
	* include/c_global/cmath (isfinite, isinf, isnan): Likewise.
	* include/std/chrono (zoned_time): Likewise.
	* include/std/future (__future_base::_S_allocate_result):
	Likewise.
	(packaged_task): Likewise.
	* include/std/optional (_Optional_payload_base): Likewise.
	* include/std/scoped_allocator (__inner_type_impl): Likewise.
	* include/std/tuple (_Tuple_impl): Likewise.

12 files changed, 26 insertions, 26 deletions

diff --git a/libstdc++-v3/include/bits/alloc_traits.h b/libstdc++-v3/include/bits/alloc_traits.h
index 182c3e2..bc936ec 100644
--- a/libstdc++-v3/include/bits/alloc_traits.h
+++ b/libstdc++-v3/include/bits/alloc_traits.h
@@ -493,7 +493,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       */
       [[__nodiscard__,__gnu__::__always_inline__]]
       static _GLIBCXX20_CONSTEXPR pointer
-      allocate(allocator_type& __a, size_type __n, const_void_pointer __hint)
+      allocate(allocator_type& __a, size_type __n,
+	       [[maybe_unused]] const_void_pointer __hint)
       {
 #if __cplusplus <= 201703L
 	return __a.allocate(__n, __hint);
diff --git a/libstdc++-v3/include/bits/regex_executor.tcc b/libstdc++-v3/include/bits/regex_executor.tcc
index 38fbe3d..9643a35 100644
--- a/libstdc++-v3/include/bits/regex_executor.tcc
+++ b/libstdc++-v3/include/bits/regex_executor.tcc
@@ -339,7 +339,7 @@ namespace __detail
   template<typename _BiIter, typename _TraitsT>
     struct _Backref_matcher
     {
-      _Backref_matcher(bool __icase, const _TraitsT& __traits)
+      _Backref_matcher(bool /* __icase */, const _TraitsT& __traits)
       : _M_traits(__traits) { }
 
       bool
diff --git a/libstdc++-v3/include/bits/shared_ptr_atomic.h b/libstdc++-v3/include/bits/shared_ptr_atomic.h
index 2295b48..3f921d3 100644
--- a/libstdc++-v3/include/bits/shared_ptr_atomic.h
+++ b/libstdc++-v3/include/bits/shared_ptr_atomic.h
@@ -99,7 +99,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   */
   template<typename _Tp, _Lock_policy _Lp>
     inline bool
-    atomic_is_lock_free(const __shared_ptr<_Tp, _Lp>* __p)
+    atomic_is_lock_free(const __shared_ptr<_Tp, _Lp>*)
     {
 #ifdef __GTHREADS
       return __gthread_active_p() == 0;
diff --git a/libstdc++-v3/include/bits/stl_uninitialized.h b/libstdc++-v3/include/bits/stl_uninitialized.h
index be7b4afd..474a9a1 100644
--- a/libstdc++-v3/include/bits/stl_uninitialized.h
+++ b/libstdc++-v3/include/bits/stl_uninitialized.h
@@ -806,8 +806,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     {
       template<typename _ForwardIterator>
         static void
-        __uninit_default_novalue(_ForwardIterator __first,
-				 _ForwardIterator __last)
+        __uninit_default_novalue(_ForwardIterator, _ForwardIterator)
 	{
 	}
     };
diff --git a/libstdc++-v3/include/bits/streambuf_iterator.h b/libstdc++-v3/include/bits/streambuf_iterator.h
index 32285a6..14a95ad 100644
--- a/libstdc++-v3/include/bits/streambuf_iterator.h
+++ b/libstdc++-v3/include/bits/streambuf_iterator.h
@@ -223,7 +223,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #if __cplusplus > 201703L && __cpp_lib_concepts
       [[nodiscard]]
       friend bool
-      operator==(const istreambuf_iterator& __i, default_sentinel_t __s)
+      operator==(const istreambuf_iterator& __i, default_sentinel_t)
       { return __i._M_at_eof(); }
 #endif
     };
diff --git a/libstdc++-v3/include/bits/uses_allocator.h b/libstdc++-v3/include/bits/uses_allocator.h
index d3b26c7..ebd26d2 100644
--- a/libstdc++-v3/include/bits/uses_allocator.h
+++ b/libstdc++-v3/include/bits/uses_allocator.h
@@ -168,7 +168,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #endif // C++14
 
   template<typename _Tp, typename... _Args>
-    void __uses_allocator_construct_impl(__uses_alloc0 __a, _Tp* __ptr,
+    void __uses_allocator_construct_impl(__uses_alloc0, _Tp* __ptr,
 					 _Args&&... __args)
     { ::new ((void*)__ptr) _Tp(std::forward<_Args>(__args)...); }
 
diff --git a/libstdc++-v3/include/c_global/cmath b/libstdc++-v3/include/c_global/cmath
index b0ba395..caa95e3 100644
--- a/libstdc++-v3/include/c_global/cmath
+++ b/libstdc++-v3/include/c_global/cmath
@@ -1135,7 +1135,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   template<typename _Tp>
     constexpr typename __gnu_cxx::__enable_if<__is_integer<_Tp>::__value,
                                               bool>::__type
-    isfinite(_Tp __x)
+    isfinite(_Tp)
     { return true; }
 #endif
 
@@ -1162,7 +1162,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   template<typename _Tp>
     constexpr typename __gnu_cxx::__enable_if<__is_integer<_Tp>::__value,
                                               bool>::__type
-    isinf(_Tp __x)
+    isinf(_Tp)
     { return false; }
 #endif
 
@@ -1189,7 +1189,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   template<typename _Tp>
     constexpr typename __gnu_cxx::__enable_if<__is_integer<_Tp>::__value,
                                               bool>::__type
-    isnan(_Tp __x)
+    isnan(_Tp)
     { return false; }
 #endif
 
diff --git a/libstdc++-v3/include/std/chrono b/libstdc++-v3/include/std/chrono
index 660e8d2..9b16048 100644
--- a/libstdc++-v3/include/std/chrono
+++ b/libstdc++-v3/include/std/chrono
@@ -3039,7 +3039,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	template<typename _Duration2, typename _TimeZonePtr2>
 	  zoned_time(_TimeZonePtr __z,
 		     const zoned_time<_Duration2, _TimeZonePtr2>& __zt,
-		     choose __c)
+		     choose)
 	  requires is_convertible_v<sys_time<_Duration2>, sys_time<_Duration>>
 	  : _M_zone(__z), _M_tp(__zt._M_tp)
 	  { }
@@ -3057,7 +3057,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	template<typename _Duration2, typename _TimeZonePtr2>
 	  zoned_time(string_view __name,
 		     const zoned_time<_Duration2, _TimeZonePtr2>& __zt,
-		     choose __c)
+		     choose)
 	  requires is_convertible_v<sys_time<_Duration2>, sys_time<_Duration>>
 	  && requires {
 	    { _Traits::locate_zone(__name) } -> convertible_to<_TimeZonePtr>;
diff --git a/libstdc++-v3/include/std/future b/libstdc++-v3/include/std/future
index 95b413a..b94ae0b 100644
--- a/libstdc++-v3/include/std/future
+++ b/libstdc++-v3/include/std/future
@@ -314,7 +314,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     // Keep it simple for std::allocator.
     template<typename _Res, typename _Tp>
       static _Ptr<_Result<_Res>>
-      _S_allocate_result(const std::allocator<_Tp>& __a)
+      _S_allocate_result(const std::allocator<_Tp>&)
       {
 	return _Ptr<_Result<_Res>>(new _Result<_Res>);
       }
@@ -1574,7 +1574,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       // _GLIBCXX_RESOLVE_LIB_DEFECTS
       // 2095.  missing constructors needed for uses-allocator construction
       template<typename _Allocator>
-	packaged_task(allocator_arg_t, const _Allocator& __a) noexcept
+	packaged_task(allocator_arg_t, const _Allocator&) noexcept
 	{ }
 
       template<typename _Allocator>
diff --git a/libstdc++-v3/include/std/optional b/libstdc++-v3/include/std/optional
index bcac152..85e814c 100644
--- a/libstdc++-v3/include/std/optional
+++ b/libstdc++-v3/include/std/optional
@@ -138,7 +138,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       // Constructor used by _Optional_base copy constructor when the
       // contained value is not trivially copy constructible.
       constexpr
-      _Optional_payload_base(bool __engaged,
+      _Optional_payload_base(bool /* __engaged */,
 			     const _Optional_payload_base& __other)
       {
 	if (__other._M_engaged)
@@ -148,7 +148,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       // Constructor used by _Optional_base move constructor when the
       // contained value is not trivially move constructible.
       constexpr
-      _Optional_payload_base(bool __engaged,
+      _Optional_payload_base(bool /* __engaged */,
 			     _Optional_payload_base&& __other)
       {
 	if (__other._M_engaged)
diff --git a/libstdc++-v3/include/std/scoped_allocator b/libstdc++-v3/include/std/scoped_allocator
index a115450..cb15c8c 100644
--- a/libstdc++-v3/include/std/scoped_allocator
+++ b/libstdc++-v3/include/std/scoped_allocator
@@ -104,11 +104,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __inner_type_impl& operator=(__inner_type_impl&&) = default;
 
       template<typename _Alloc>
-      __inner_type_impl(const __inner_type_impl<_Alloc>& __other) noexcept
+      __inner_type_impl(const __inner_type_impl<_Alloc>&) noexcept
       { }
 
       template<typename _Alloc>
-      __inner_type_impl(__inner_type_impl<_Alloc>&& __other) noexcept
+      __inner_type_impl(__inner_type_impl<_Alloc>&&) noexcept
       { }
 
       __type&
diff --git a/libstdc++-v3/include/std/tuple b/libstdc++-v3/include/std/tuple
index 0e47abe..c9ea2a8 100644
--- a/libstdc++-v3/include/std/tuple
+++ b/libstdc++-v3/include/std/tuple
@@ -564,14 +564,14 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 
       template<typename _Alloc>
 	_GLIBCXX20_CONSTEXPR
-	_Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
+	_Tuple_impl(allocator_arg_t, const _Alloc& __a,
 		    const _Head& __head)
 	: _Base(__use_alloc<_Head, _Alloc, const _Head&>(__a), __head)
 	{ }
 
       template<typename _Alloc, typename _UHead>
 	_GLIBCXX20_CONSTEXPR
-	_Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
+	_Tuple_impl(allocator_arg_t, const _Alloc& __a,
 		    _UHead&& __head)
 	: _Base(__use_alloc<_Head, _Alloc, _UHead>(__a),
 		std::forward<_UHead>(__head))
@@ -579,14 +579,14 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 
       template<typename _Alloc>
 	_GLIBCXX20_CONSTEXPR
-	_Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
+	_Tuple_impl(allocator_arg_t, const _Alloc& __a,
 		    const _Tuple_impl& __in)
 	: _Base(__use_alloc<_Head, _Alloc, const _Head&>(__a), _M_head(__in))
 	{ }
 
       template<typename _Alloc>
 	_GLIBCXX20_CONSTEXPR
-	_Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
+	_Tuple_impl(allocator_arg_t, const _Alloc& __a,
 		    _Tuple_impl&& __in)
 	: _Base(__use_alloc<_Head, _Alloc, _Head>(__a),
 		std::forward<_Head>(_M_head(__in)))
@@ -594,7 +594,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 
       template<typename _Alloc, typename _UHead>
 	_GLIBCXX20_CONSTEXPR
-	_Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
+	_Tuple_impl(allocator_arg_t, const _Alloc& __a,
 		    const _Tuple_impl<_Idx, _UHead>& __in)
 	: _Base(__use_alloc<_Head, _Alloc, const _UHead&>(__a),
 		_Tuple_impl<_Idx, _UHead>::_M_head(__in))
@@ -602,7 +602,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 
       template<typename _Alloc, typename _UHead>
 	_GLIBCXX20_CONSTEXPR
-	_Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
+	_Tuple_impl(allocator_arg_t, const _Alloc& __a,
 		    _Tuple_impl<_Idx, _UHead>&& __in)
 	: _Base(__use_alloc<_Head, _Alloc, _UHead>(__a),
 		std::forward<_UHead>(_Tuple_impl<_Idx, _UHead>::_M_head(__in)))
@@ -611,7 +611,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #if __cplusplus > 202002L
       template<typename _Alloc, typename _UHead>
 	constexpr
-	_Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
+	_Tuple_impl(allocator_arg_t, const _Alloc& __a,
 		    _Tuple_impl<_Idx, _UHead>& __in)
 	: _Base(__use_alloc<_Head, _Alloc, _UHead&>(__a),
 		_Tuple_impl<_Idx, _UHead>::_M_head(__in))
@@ -619,7 +619,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 
       template<typename _Alloc, typename _UHead>
 	constexpr
-	_Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
+	_Tuple_impl(allocator_arg_t, const _Alloc& __a,
 		    const _Tuple_impl<_Idx, _UHead>&& __in)
 	: _Base(__use_alloc<_Head, _Alloc, const _UHead>(__a),
 		std::forward<const _UHead>(_Tuple_impl<_Idx, _UHead>::_M_head(__in)))