bug#19973: Grafts break debug outputs

[ludo@gnu.org (Ludovic Courtès)]

Hello Timothy,

Timothy Sample <samplet@ngyro.com> skribis:

> ludo@gnu.org (Ludovic Courtès) writes:

[...]

>> Next we can fix build IDs similarly (see <https://bugs.gnu.org/25752>),
>> and maybe the Racket CRC issue that Timothy and Chris looked at
>> recently, and maybe the Java manifest issue as well (is it still
>> relevant?).
>
> The only concern I have is the level at which the hooks operate.  In my
> draft patch¹ I had the hooks running both on the client side and the
> build side.  This made it possible to get a bit more information about
> the derivation being grafted.  If everything happens at the build level
> based on outputs, we will only be able to look at the structures and
> names of the outputs.

Yes, I agree that your proposal had the appeal of being possibly more
extensible that what I posted here.  However, as I wrote there, there
are hooks that we’ll always want to run, independently of the input
packages, such as the .gnu_debuglink and build-ID hooks; also, it costs
nothing to have them unconditionally, we only pay for their
functionality when candidate files exist.

> That being said, this is probably okay.  The Racket hook will just have
> to check for “share/racket” to determine if it runs (and fail safely if
> anything is amiss).

Yes, that should work well enough.

Thanks for your feedback!

Ludo’.