[Bug libstdc++/56677] [ratio] : ratio_multiply, ratio_divide, etc results doesnt verify as __is_ratio

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56677

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |rejects-valid
      Known to work|                            |4.8.0

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> 2013-03-21 13:44:21 UTC ---
The workaround is simply:

std::chrono::duration<unsigned long, ratii1::type > d1;

I don't think we want to backport the fix, as it would break compatibility with
existing 4.7.x releases.