Want reasonable reference counting? Disable automatic sharing of immutable

[Elronnd]

On Saturday, 13 November 2021 at 23:08:01 UTC, Stanislav Blinov 
wrote:
> Read `a`, call pure function, read `a`. Where is it possible 
> for `a` to mutate, after first read and before second read? 
> Can't be the pure function, it's pure and cant mutate `a`. So
> where is it possible for `a` to mutate?

auto x = new int;
assert(a < 5);
auto y = new int;
assert(a < 5);
*x += *y;

Would you begrudge the compiler the ability to remove the second 
assert?  Because there is the _exact_ same problem there.

Actually, forget allocation.  A signal can occur at _any_ time, 
and its handler can change globals.

> Can't be another thread, `a` is a thread-local int.

You can share pointers to thread-local objects.