On Tue, 2021-03-23 at 15:22 +0100, Andreas Enge wrote:
> I wrote in my bug report https://issues.guix.gnu.org/47315; grafts
> with
> different version numbers lead to a command line behaviour that is
> not
> understandable:
> 
> $ guix package -A imagemagick
> imagemagick	6.9.12-2g	out,doc	gnu/packages/imagemagick.scm:132:2
> imagemagick	6.9.11-48	out,doc	gnu/packages/imagemagick.scm:48:2
> 
> $ guix build imagemagick@6.9.11
> guix build: error: imagemagick: package not found for version 6.9.11
> 
> $ guix build imagemagick@6.9.11-48
> /gnu/store/c30y49vg735g6b4hh590zrc9fmvcsy0w-imagemagick-6.9.12-2g-doc
> /gnu/store/l3hr0fimip6v7vmkgxbqygsglxaxasy0-imagemagick-6.9.12-2g
> 
> From a user's perspective, inkscape@6.9.11 is at the time there and
> not
> there; it is shown by "guix package", but then not accessible for
> install-
> ation, but silently "glossed over" in favour of a different version.
> 
> I just noticed that I can do this:
> $ guix build imagemagick@6.9.11-48 --no-grafts
> /gnu/store/wlnciwhn6llwqwywf4hq739v5bbcrq3h-imagemagick-6.9.11-48-doc
> /gnu/store/vlix7fclb7ifjgmxgpwr1pvraff89w7b-imagemagick-6.9.11-48
> But I can also do this:
> $ guix build imagemagick@6.9.12-2g --no-grafts
> /gnu/store/4s20df0zjmmys8zvlvynksrwz5xqk9ls-imagemagick-6.9.12-2g-doc
> /gnu/store/7iwx7rj1ipsbgb9wgimrrflniyxpilw3-imagemagick-6.9.12-2g
> where I do not know what I would have expected - the ungrafted
> version
> of 6.9.12 is 6.9.11, no? At the same time, for once it respects my
> wish for a specific version.
> 
> Otherwise said, grafting to different versions breaks our semantic
> for
> designating packages, in which version numbers play an important
> role,
> and replaces it by a mess which even with the examples above I have a
> hard time understanding.

For this, the problem is not grafting but that the replacement package
definition has been made public, this is an "issue" (?) that is known
and I try to not make replacement package definitions public now.

>  
> Caeterum censeo:
> The real fix is probably to do less grafts and more rebuilds...

Agreed, I would really like a security-updates branch for that, with
which we can buffer changes waiting for substitutes and then merge with
master, but I am afraid this enters in conflict with people not having
lots of bandwidth to download a new world again through substitutes or
very powerful machines for those who don't use substitutes.

Léo