[Bug c++/69600] Incorrect use of copy-assignment instead of move assignment from function

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69600

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
The value_type of your map is pair<const std::string, inner_data_t> an you
can't move the first part of that pair, and you can't copy the second part of
that pair, so you can't move or copy it.