I think we agree, though, that a deterministic dynamic set of files is in
scope for any serious build system, and non-deterministic is out of scope
and not something we need to worry about letting C++ do?

That is, yes, you could do that, it just won't work, and that's user error
not a problem with the facility? It's not a reason to not have the
facility.

Compile time io has other reasons to worry me. But not because of build
systems.

On Thu, Oct 31, 2024, 06:17 Boris Kolpackov <boris_at_[hidden]> wrote:

> Steve Downey <sdowney_at_[hidden]> writes:
>
> > [...] but the description of dependency could be produced as a
> > side-effect of compilation, and would not affect the shape of
> > the graph.
>
> Unless the dependencies are auto-generated, right?
>
> You may disagree, but at this day and age I don't think you
> can call a build system that cannot handle auto-generated
> headers modern or general-purpose.
>
>
> > a build system generator
>
> Not every build system is a meta-build system (and thus has a
> a generator and all the problems and limitations stemming from
> it). In fact, if you look at modern build systems (Bazel, Buck2,
> build2), none of them are meta-build systems.
>