libstdc++: Fix std::hash<std::stacktrace> [PR112348]

libstdc++-v3/ChangeLog:

	PR libstdc++/112348
	* include/std/stacktrace (hash<basic_stacktrace<Alloc>>): Fix
	type of hash functio nfor entries.
	* testsuite/19_diagnostics/stacktrace/hash.cc: New test.

libstdc++-v3/include/std/stacktrace

@@ -797,7 +797,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       size_t
       operator()(const basic_stacktrace<_Allocator>& __st) const noexcept
       {
-	hash<stacktrace_entry::native_handle_type> __h;
+	hash<stacktrace_entry> __h;
 	size_t __val = _Hash_impl::hash(__st.size());
 	for (const auto& __f : __st)
 	  __val = _Hash_impl::__hash_combine(__h(__f), __val);

libstdc++-v3/testsuite/19_diagnostics/stacktrace/hash.cc

+// { dg-options "-lstdc++exp" }
+// { dg-do run { target c++23 } }
+// { dg-require-effective-target stacktrace }
+
+#include <stacktrace>
+#include <testsuite_allocator.h>
+#include <testsuite_hooks.h>
+
+void
+test_hash()
+{
+  using Alloc = __gnu_test::uneq_allocator<std::stacktrace_entry>;
+  using S = std::basic_stacktrace<Alloc>;
+  S s;
+  std::size_t h = std::hash<S>()(s);
+  std::size_t h2 = std::hash<S>()(S::current());
+  VERIFY( h != h2 );
+}
+
+int main()
+{
+  test_hash();
+}