[Bug libstdc++/71945] Integer overflow in use counter of shared pointers

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71945

Jonathan Wakely  changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2025-01-23
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1

--- Comment #2 from Jonathan Wakely  ---
We should terminate if the counter reaches its maximum value.

We could also consider treating the counters as unsigned, which would double
their range. I think that could be done an an ABI-compatible way, because no
correct programs overflow the counters into negative values today.