[Nix-dev] Cycle detected in references when building systemd

[Eelco Dolstra]

Hi,

On 10/10/2016 02:43 PM, Jan Synáček wrote:

>> You can find the exact cause of these cycles using good old "grep -r".
> 
> Pardon my ignorance, but I still can't see where the cycle is and how
> you managed to figure it out. In this particular case, the cycle (at
> least a part of it) is supposed to be somewhere in
> '/nix/store/2ipa3ipr85ywzq61366cg7ymk7n6bqg6-systemd-master-lib'
> according to the error message. But that's all what it says... Maybe
> the message could be more helpful? 

It already is on Nix master, which prints both paths in the cycle, i.e.

  cycle detected in the references of '/nix/store/<foo>' from '/nix/store/<bar>'

so then you can do

  grep -r <bar> /nix/store/<foo>

to find which file has the reference. Obviously it would be nicer if Nix printed
this automatically...

-- 
Eelco Dolstra | LogicBlox, Inc. | http://nixos.org/~eelco/