libstdc++: Implement LWG 3580 change to ranges::iota_view

libstdc++-v3/ChangeLog:

	* include/std/ranges (iota_view::_Iterator::operator+): Adjust
	definition as per LWG 3580.
	(iota_view::_Iterator::operator-): Likewise.

diff --git a/libstdc++-v3/include/std/ranges b/libstdc++-v3/include/std/ranges
index c3a6dbab6fd2a45c734d3637bd94e1dd9a78d21d..273699aa7900c996cc1fb06c221b9b0aa612f0e2 100644 (file)
--- a/libstdc++-v3/include/std/ranges
+++ b/libstdc++-v3/include/std/ranges
@@ -497,7 +497,10 @@ namespace ranges
        friend constexpr _Iterator
        operator+(_Iterator __i, difference_type __n)
          requires __detail::__advanceable<_Winc>
-       { return __i += __n; }
+       {
+         __i += __n;
+         return __i;
+       }
 
        friend constexpr _Iterator
        operator+(difference_type __n, _Iterator __i)
@@ -507,7 +510,10 @@ namespace ranges
        friend constexpr _Iterator
        operator-(_Iterator __i, difference_type __n)
          requires __detail::__advanceable<_Winc>
-       { return __i -= __n; }
+       {
+         __i -= __n;
+         return __i;
+       }
 
        friend constexpr difference_type
        operator-(const _Iterator& __x, const _Iterator& __y)