/etc/localtime is missing in 2021.03 compat layer

[boegel]

This causes timezone confusion for some software, see EESSI/software-layer#79 .

We do have /etc/localtime in the 2020.12 compat layer:

cat /cvmfs/pilot.eessi-hpc.org/2020.12/compat/linux/x86_64/etc/localtime
TZif2-00TZif2-00
<-00>0

We should make this a symlink into the host, to get correct time zone information?

ln -s /etc/localtime /cvmfs/pilot.eessi-hpc.org/2021.03/compat/linux/x86_64/etc/localtime

[bedroge]

Apparently this was caused by an update of sys-libs/timezone-data, see gentoo/gentoo@c4bf952#diff-6b1379cb55d60e0b6dc6cc2be8a09b90cf10e403b82bc8c825fef1ccc18717ad

[boegel]

@bedroge This one was fixed somehow, right? (how?)
So we can close it?

[bedroge]

I wasn't sure if we had already fixed it, but I don't see the symlink here, so I guess it hasn't been fixed:
https://github.com/EESSI/compatibility-layer/blob/main/ansible/playbooks/roles/compatibility_layer/defaults/main.yml#L52

[boegel]

We danced around this problem by defining $TZ where is matters (when installing R, since this was breaking the installation of the rstan instance), see EESSI/software-layer@86e5ca9 .

For the next iteration of the EESSI pilot, we should fix this, so we can stopping setting $TZ when installing R...