[Bug libstdc++/79254] basic_string::operator= isn't exception safe

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79254

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2017-01-27
     Ever confirmed|0                           |1

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
It's wrong to say it's not exception-safe, because it is, but it only meets the
basic exception-safety guarantee, not the strong one required by
[string.require] p2.

I think I looked at solving this when implementing the new basic_string and
decided I didn't care about POCMA allocators enough to do it.