Comment by ori_b
1 year ago
The problem with doing it in rust is that most calls aren't tail calls, even if they look like tail calls. You need to invoke the destructors for any code path that can drop.
1 year ago
The problem with doing it in rust is that most calls aren't tail calls, even if they look like tail calls. You need to invoke the destructors for any code path that can drop.
Isn't that the purpose of `become`? I thought it was to say "this IS a tail call, error out if it is not". After that validation is done, then the compiler can drop as needed.
The compiler can't drop as needed, because the drop prevents things from being tail calls. A single drop in a function prevents any calls from being tail calls, and therefore, they can't be eliminated.
In idiomatic rust, this means very few functions can use become.