[Nix-dev] Strange log

[Arseniy Seroka]

I did `nixos-rebuild switch --upgrade` and now I'm getting in my log:
```
setting up /etc...
Use of uninitialized value in numeric comparison (<=>) at /nix/store/
a218r8idpw52c652vy44d9zvfjf82jbc-update-users-groups.pl line 141.
Use of uninitialized value in numeric comparison (<=>) at /nix/store/
a218r8idpw52c652vy44d9zvfjf82jbc-update-users-groups.pl line 141.
Use of uninitialized value in numeric comparison (<=>) at /nix/store/
a218r8idpw52c652vy44d9zvfjf82jbc-update-users-groups.pl line 141.
Use of uninitialized value in numeric comparison (<=>) at /nix/store/
a218r8idpw52c652vy44d9zvfjf82jbc-update-users-groups.pl line 141.
Use of uninitialized value in numeric comparison (<=>) at /nix/store/
a218r8idpw52c652vy44d9zvfjf82jbc-update-users-groups.pl line 141.
Use of uninitialized value in join or string at /nix/store/
a218r8idpw52c652vy44d9zvfjf82jbc-update-users-groups.pl line 141.
Use of uninitialized value in numeric comparison (<=>) at /nix/store/
a218r8idpw52c652vy44d9zvfjf82jbc-update-users-groups.pl line 215.
Use of uninitialized value in numeric comparison (<=>) at /nix/store/
a218r8idpw52c652vy44d9zvfjf82jbc-update-users-groups.pl line 215.
Use of uninitialized value in numeric comparison (<=>) at /nix/store/
a218r8idpw52c652vy44d9zvfjf82jbc-update-users-groups.pl line 215.
Use of uninitialized value in numeric comparison (<=>) at /nix/store/
a218r8idpw52c652vy44d9zvfjf82jbc-update-users-groups.pl line 215.
Use of uninitialized value in numeric comparison (<=>) at /nix/store/
a218r8idpw52c652vy44d9zvfjf82jbc-update-users-groups.pl line 215.
Use of uninitialized value in join or string at /nix/store/
a218r8idpw52c652vy44d9zvfjf82jbc-update-users-groups.pl line 215.
mv: ‘/usr/bin/.env.tmp’ and ‘/usr/bin/env/.env.tmp’ are the same file
warning: error(s) occured while switching to the new configuration
```

What is that?
And what do I need to fix?

-- 
Sincerely,
Arseniy Seroka
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.science.uu.nl/pipermail/nix-dev/attachments/20151025/9a4a3199/attachment-0001.html