https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105284
Bug ID: 105284
Summary: missing syncstream and spanstream forward decl. in
<iosfwd>
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: cooky.ykooc922 at gmail dot com
Target Milestone: ---
according to https://wg21.link/iosfwd.syn's <iosfwd> sypnosis:
The followings are declared (forward declaration only) which are added in C++20
and C++23:
* class template std::basic_spanbuf
* typedef std:spanbuf
* typedef std::wspanbuf
* class template std::basic_ispanstream
* typedef std::ispanstream
* typedef std::wispanstream
* class template std::basic_ospanstream
* typedef std::ospanstream
* typedef std::wospanstream
* class template std::basic_spanstream
* typedef std::spanstream
* typedef std::wspanstream
* class template std::basic_syncbuf
* typedef std::syncbuf
* typedef std::wsyncbuf
* class template std::basic_osyncstream
* typedef std::osyncstream
* typedef std::wosyncstream
However, they are currently not added in the current header <iosfwd> of
libstdc++
