alt Hacker NewsClang tail-calls aren't guaranteed to work with all C++ code. If you have a non-trivial constructor, as you mention, it will tell you this and fail instead of silently letting you believe you have tail-calls when you don't.
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tialaramex • today at 6:37 PM
I have to say that at least knowing if I didn't get what I wanted is most of the value for me.
There are far more cases. Some ABIs use callee-saved registers for parameter-passing under certain circumstances, for example. Usually, there are compatibility restrictions on the signatures of the current and tail-called functions beyond the return type, too.
This is different from Scheme or the MLs (there as a quality-of-implementation feature) where tail calls into arbitrary functions are expected not to lead to space leaks.