Thanks for the pointer, you are correct: [class.temporary] paragraph
6.4 documents that.

This wasn't an interaction that I'd anticipated. At first glance this
seems to be a desirable side-effect. And part of the point of this
paper is that folk shouldn't have to write their own operator-> in
most cases (though it doesn't prevent one from doing so if there's a
reason to).

On Fri, Feb 20, 2026 at 10:47 AM Marcin Jaczewski
<marcinjaczewski86_at_[hidden]> wrote:
>
> pt., 20 lut 2026 o 19:42 Andre Kostur <andre_at_[hidden]> napisał(a):
> >
> > It wouldn't though: foo would't be binding to a temporary, it would be
> > binding to the result of doing ".member" on the temporary.
> >
>
> I recall there is rule when you bind to a member then the whole object
> get lifetime expanded.
> Consider this code:
>
> ```
> #include <cstdio>
>
> struct bar {
> bar () { std::puts("start"); }
> ~bar () { std::puts("end"); }
>
> int i;
>
> };
>
>
> bar foo()
> {
> return {};
> }
>
> int main() {
> const auto& i = foo().i;
> std::puts("work");
> }
> ```
>
> its print:
>
> ```
> start
> work
> end
> ```
>
> https://godbolt.org/z/bheoTd1n3
>
> > On Fri, Feb 20, 2026 at 10:39 AM Marcin Jaczewski via Std-Proposals
> > <std-proposals_at_[hidden]> wrote:
> > >
> > > Paper suggests rewriting `ptr->meber` by `(*ptr).member`.
> > >
> > > But this creates an interesting case, new `->` created this way will
> > > have capabilities impossible compared to manually written `->`.
> > >
> > > Consider example:
> > > ```
> > > const auto& foo = ptr->member;
> > > ```
> > > and `ptr` that has a `*` returning proxy value.
> > > With this rewrite, the lifetime of the proxy object will be expanded
> > > to the lifetime of the `foo` reference.
> > > Using user defined `->` you can't in anyway do this as this operator
> > > is required to return pointer and not value (as it will call nested of `->`).
> > >
> > > This is expected behavior? If yes then maybe we should
> > > discourage of further use of user defined `->` operator?
> > > --
> > > Std-Proposals mailing list
> > > Std-Proposals_at_[hidden]
> > > https://lists.isocpp.org/mailman/listinfo.cgi/std-proposals