On 07/04/2023 22.04, Lénárd Szolnoki via Std-Proposals wrote:
> An alternative approach is that Base has a private `virtual void
> do_fun1()` member function and a public inline `Base& fun1() {
> do_fun1(); return *this; }` member function. This should achieve the
> same performance as the proposed this return type.

I can't get any compiler convinced to do the right thing for this
setup:

https://www.godbolt.org/z/a8MTqqzvv

Jens