On Sat, 25 Jun 2022 at 13:45, Vittorio Romeo wrote: > > Thank you, Jonathan, for the very thorough explanation and for pointing out that I completely forgot to consider ABI stability in this case. > > I still think that it might be worthwhile to attempt some work in this area as multiple projects I work on have various TUs using unique_ptr but not tuple. I will look into the refactoring you suggested. Something like this would avoid instantiating most of std::tuple while preserving ABI, but it doesn't seem to really make much difference to compilation time.