[Bug libstdc++/84949] -ffast-math bugged with respect to NaNs

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84949

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2018-03-19
     Ever confirmed|0                           |1

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Christoph Lipka from comment #0)
> (B)
> std::numeric_limits<T>::has_quiet_NaN() is broken in that it claims that
> NaNs are supported.

Agreed. 

> Seen with both g++ 4.8.4 on Ubuntu 14.04, as well as g++ 5.4.0 on MS Windows
> Subsystem for Linux

Neither of those compilers is still supported by the GCC project.