[Bug libstdc++/96088] Range insertion into unordered_map is less effective than a loop with insertion

[fdumont at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96088

François Dumont <fdumont at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2020-08-04
           Assignee|unassigned at gcc dot gnu.org      |fdumont at gcc dot 
gnu.org

--- Comment #5 from François Dumont <fdumont at gcc dot gnu.org> ---
After further investigation the unordered containers are also suffering from a
problem similar to libstdc++/87194. There are several places where we
constraint the iterator value_type to be an instance of container key_type
forcing the compiler to generate temporaries.

I'll fix that so that the nice enhancements already proposed can indeed work.