[Bug libstdc++/46906] istreambuf_iterator is late?

[redi at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=46906

--- Comment #13 from Jonathan Wakely <redi at gcc dot gnu.org> ---
This seems related to https://cplusplus.github.io/LWG/issue2366 and the changes
I'm proposing there.