[syncstream.syncbuf.special] Remove 'noexcept' for non-member swap

jensmaurer · tkoeppe · commit 8753efabbbfe · 2021-10-18T22:53:33.000+01:00
LWG3498 confirmed that basic_syncbuf's member swap is not 'noexcept'. Since the non-member swap simply delegates to the member swap, the former can't be 'noexcept', either.
diff --git a/source/iostreams.tex b/source/iostreams.tex
@@ -12082,7 +12082,7 @@
 \begin{itemdecl}
 template<class charT, class traits, class Allocator>
   void swap(basic_syncbuf<charT, traits, Allocator>& a,
-            basic_syncbuf<charT, traits, Allocator>& b) noexcept;
+            basic_syncbuf<charT, traits, Allocator>& b);
 \end{itemdecl}
 
 \begin{itemdescr}
