@@ -2925,6 +2925,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
const leap_second& __y) noexcept
{ return !(__x < __y.date()); }
+ // This is a simplified form of the constraint specified in the standard,
+ // three_way_comparable_with<sys_seconds, sys_time<_Duration>>.
template<three_way_comparable_with<seconds> _Duration>
[[nodiscard]] friend constexpr auto
operator<=>(const leap_second& __x,
new file mode 100644
@@ -0,0 +1,56 @@
+// { dg-do run { target c++20 } }
+// { dg-require-effective-target tzdb }
+// { dg-require-effective-target cxx11_abi }
+
+#include <chrono>
+#include <sstream>
+#include <format>
+#include <testsuite_hooks.h>
+
+void
+test_output()
+{
+ using namespace std::chrono;
+
+ std::ostringstream out;
+ out << '\n';
+
+ for (auto& l : get_tzdb().leap_seconds)
+ if (l <= sys_days{2018y/March/17d})
+ out << l.date() << ": " << l.value() << '\n';
+
+ VERIFY( out.str() == R"(
+1972-07-01 00:00:00: 1s
+1973-01-01 00:00:00: 1s
+1974-01-01 00:00:00: 1s
+1975-01-01 00:00:00: 1s
+1976-01-01 00:00:00: 1s
+1977-01-01 00:00:00: 1s
+1978-01-01 00:00:00: 1s
+1979-01-01 00:00:00: 1s
+1980-01-01 00:00:00: 1s
+1981-07-01 00:00:00: 1s
+1982-07-01 00:00:00: 1s
+1983-07-01 00:00:00: 1s
+1985-07-01 00:00:00: 1s
+1988-01-01 00:00:00: 1s
+1990-01-01 00:00:00: 1s
+1991-01-01 00:00:00: 1s
+1992-07-01 00:00:00: 1s
+1993-07-01 00:00:00: 1s
+1994-07-01 00:00:00: 1s
+1996-01-01 00:00:00: 1s
+1997-07-01 00:00:00: 1s
+1999-01-01 00:00:00: 1s
+2006-01-01 00:00:00: 1s
+2009-01-01 00:00:00: 1s
+2012-07-01 00:00:00: 1s
+2015-07-01 00:00:00: 1s
+2017-01-01 00:00:00: 1s
+)" );
+}
+
+int main()
+{
+ test_output();
+}