[Bug libstdc++/91260] std::unary_function and std::binary_function still exist in C++17

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91260

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|INVALID                     |FIXED
   Target Milestone|---                         |12.0

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
For GCC 12 those types will still exist (because as explained above, that is
allowed by the standard) but they will give -Wdeprecated warnings.