(Note: this is on a private channel of me, but I think this is
unrelated, it could happen with any Guix package).

I updated a package-definition and forgot to update the Checksum. When
then updating, it just fails, and the new, nice, logging-reduced UI
doesn't tell:

$ guix package -u guix-tools
substitute: updating list of substitutes from 'https://berlin.guixsd.org'...   0
[..]
building /gnu/store/vy3s1y7bv1w6d8gmp5b10xppy9skbgkd-guix-tools-0.1.0-2.4f17b79-checkout.drv...
build of /gnu/store/vy3s1y7bv1w6d8gmp5b10xppy9skbgkd-guix-tools-0.1.0-2.4f17b79-checkout.drv failed
View build log at '/var/log/guix/drvs/vy/3s1y7bv1w6d8gmp5b10xppy9skbgkd-guix-tools-0.1.0-2.4f17b79-checkout.drv.bz2'.
-guix package: error: build failed: build of `/gnu/store/iwma3gq778n32mqz6y7277g67nvx1abb-guix-tools-0.1.0-2.4f17b79.drv' failed

The log was not very helpful:


Initialized empty Git repository in /gnu/store/s399g9f1k19v01rs992w5dl6aif87har-
From https://gitlab.com/hoebjo/guix-tools
 * branch            4f17b792a3882f10ca9496b2d9aeb12b97ee93e2 -> FETCH_HEAD
Note: checking out 'FETCH_HEAD'.

You are in 'detached HEAD' state. You can look around, make experimental
changes and commit them, and you can discard any commits you make in this
state without impacting any branches by performing another checkout.

If you want to create a new branch to retain commits you create, you may
do so (now or later) by using -b with the checkout command again. Example:

  git checkout -b <new-branch-name>

HEAD is now at 4f17b79 gdev: Add more package to environment.
environment variable `PATH' unset




Only when I explicitly built it, the error was shown:

$ guix build guix-tools

HEAD is now at 4f17b79 gdev: Add more package to environment.
environment variable `PATH' unset
output path `/gnu/store/s399g9f1k19v01rs992w5dl6aif87har-guix-tools-0.1.0-2.4f17b79-checkout' should have r:sha256 hash `1j4q43hk7jrys7zsmws37g6w7babzshfdb1s5myl7qwr3mcx6hnf', instead has `0b61q29915b4i6adidx3zixnx3m0zp58rjbfa9byqcz13szznc52'
build of /gnu/store/vy3s1y7bv1w6d8gmp5b10xppy9skbgkd-guix-tools-0.1.0-2.4f17b79-checkout.drv failed
View build log at '/var/log/guix/drvs/vy/3s1y7bv1w6d8gmp5b10xppy9skbgkd-guix-tools-0.1.0-2.4f17b79-checkout.drv.bz2'.
cannot build derivation `/gnu/store/iwma3gq778n32mqz6y7277g67nvx1abb-guix-tools-0.1.0-2.4f17b79.drv': 1 dependencies couldn't be built
guix build: error: build failed: build of `/gnu/store/iwma3gq778n32mqz6y7277g67nvx1abb-guix-tools-0.1.0-2.4f17b79.drv' failed


Is it intended that this build-failure detail is not shown? I suppose
not. At least in a log it should be shown.

Björn