[Bug c/116016] enhancement: add __builtin_set_counted_by(P->FAM, COUNT) or equivalent

[siddhesh at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116016

--- Comment #26 from Siddhesh Poyarekar <siddhesh at gcc dot gnu.org> ---
(In reply to Qing Zhao from comment #25)
> If (__builtin_get_counted_by (P->FAM))
>   __builtin_get_counted_by (P->FAM) = COUNT;

Do we have language constructs where the existence of an identifier/expression
(and not its value) is evaluated in a condition like this?