Question about a alternative impacting on an other

[Sylvestre Ledru <sylvestre@debian.org>]

Hello,

I have a question about alternatives.

There is what I currently have. 
I have two important linear algebra librairies which are managed by
update-alternatives as primary:
* libblas.so.3gf
* liblapack.so.3gf

There are have various implementations. For now, we have a few of them:
* refblas for libblas.
* lapack for lapack.
* atlas which provides both.

Switching to Atlas will update both blas and lapack alternatives.

This will work.

However, if manually, I update liblapack to Atlas:
update-alternatives --config liblapack.so.3gf
Obviously, it won't update the libblas.so.3gf.

In theory, this should not be a problem... However, lapack from Atlas
uses some internal of libblas.so.
IE, if the user has libblas.so configured as refblas.so and liblapack.so
as Atlas. This will break (cf bug #598638).

Is there a way to have a kind of trigger in update-alternatives for this
case ?

Thanks
Sylvestre
PS: Please CC, I am not subscribed.