LWG3306 ranges::advance violates its preconditions

burblebee · tkoeppe · commit 5fa25465822f · 2020-12-14T01:29:40.000Z
diff --git a/source/iterators.tex b/source/iterators.tex
@@ -2855,6 +2855,7 @@
 \begin{itemdescr}
 \pnum
 \expects
+Either \tcode{assignable_from<I\&, S> || sized_sentinel_for<S, I>} is modeled, or
 \range{i}{bound} denotes a range.
 
 \pnum
