Re: [jamboost] Link compatibility

From: David Abrahams (david.abrahams_at_[hidden])
Date: 2002-05-03 08:03:01

----- Original Message -----
From: "Vladimir Prus" <ghost_at_[hidden]>

> Hi,
> I'm just about to commit property.jam with the rules
apply-requirements and
> compose-requirements that I was talking about previously. They are
needed to
> complete project.jam. However, I need a notion of link-incompatible
features.
> I have implemented it by simply creating new feature attribute,
> 'link-incompatible'. It says targets with different value of the
feature
> cannot be linked together. Any objections?

Well, it doesn't capture all of the relationships we need. For example,
<shared-linkable>true is link-compatible with everything, but
<shared-linkable>false is not. In other words, it's not always a
reflexive relationship.

Hmm, maybe that is just an artifact of some v1 mis-design.

Let me try to put it more clearly:

The "normal" value of <shared-linkable> should be false, since we don't
want to impost -fPIC where it's unneeded. A target built with
<shared-linkable>true cannot be linked with any dependencies having
<shared-linkable>false. However, a target built with
<shared-linkable>false can be linked with a dependency which is
<shared-linkable>true, no problem.

-Dave