[Bug c/122705] Add function attributes to mark functions that return a pointer parameter, verbatim or derived

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122705

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Alejandro Colomar from comment #1)
> For consistency with the ones I proposed here, it could be called
> [[gnu::returns_unique_ptr]].

malloc has more effects than returns_unique_ptr though so that is NOT a good
name.