On Sat, Jul 17, 2010 at 03:32:04PM +0200, Ludovic Courtès wrote: > Hi Lluís! > > Lluís Batlle i Rossell <[email protected]> writes: > > > I have the idea that NixOS expressions usually don't need a compiler, but > > NixOS > > relies on the nixpkgs expressions that need a compiler. > > Which are “the nixpkgs expressions that need a compiler” you’re > referring to? > In theory, if everything you need is available pre-compiled, you don’t > need a compiler. Am I overlooking cases where this isn’t true?
Do you think that hydra builds every nixpkgs package you may need? It builds a lot, but not all (1st point). Additionally, it is a heavy operation for a computer to evaluate the current nixpkgs (2nd point). Having those nixpkgs pointing mostly to fetchurl derivations instead of usual stdenv mkDerivations, it makes additionally a fence against building natively or cross-building those packages (3rd point). Then you could have x86_64 hydra cross-building for mipsel, and evaluate a nixos in that mipsel (instead of evaluating a cross-nixos - whose expression still does not exist - in x86_64), this nixos taking the packages from hydra (so being able to type nixos-rebuild in your embedded). I wonder if the current nixos implementation (namely, the modules) make nixos a heavy evaluation, even with light nixpkgs. Eelco Dolstra may know that better, as he made the new evaluator with nixos modules in mind I think. The embedded system may need the garbage collector Eelco talked about from time to time. Regards, Lluís. _______________________________________________ nix-dev mailing list [email protected] https://mail.cs.uu.nl/mailman/listinfo/nix-dev
