Re: [boost] build free-features

From: David Abrahams (david.abrahams_at_[hidden])
Date: 2001-11-21 08:19:15

----- Original Message -----
From: "Thomas Witt" <witt_at_[hidden]>

>
> Ok, it took me a bit to find out, but

> What actually happens is: they are not propagated to subprojects or
dependent
> projects.

Hmm; I'm fairly certain that they /are/ propagated to subprojects, in the
sense that the BUILD settings affect all targets which are direct
dependencies of the target you specify on the command line (or "all" if none
is specified).

I don't see how propagation to a dependent target could be relevant; the
build proceeds from the target you specify to all of its dependencies, not
the other way around.

I know that free features are not propagated to top-level targets which are
specified as dependencies with <lib>name. That's because free features are
assumed to not affect link-compatibility, so you may already have a suitable
build of the dependency lying around.

Does that make sense? I hope so.
You can affect the BUILD settings of all targets which don't have an
explicit default build specification by setting the default-BUILD variable.
Perhaps this mechanism isn't too well thought out, and something more
explicit is needed...

-Dave