Commit d3abae8d authored by Alois Wohlschlager's avatar Alois Wohlschlager Committed by Yureka
Browse files

nixos/top-level: improve replaceRuntimeDependencies 

Instead of iterating over all replacements and applying them one by one,
use the newly introduced replaceDependencies function to apply them all
at once for replaceRuntimeDependencies. The advantages are twofold in
case there are multiple replacements:
* Performance is significantly improved, because there is only one pass
  over the closure to be made.
* Correctness is improved, because replaceDependencies also replaces
  dependencies of the replacements themselves if applicable.

Fixes: https://github.com/NixOS/nixpkgs/issues/4336
parent af3a3f64

nixos/modules/system/activation/top-level.nix

+11 −3
Original line number Diff line number Diff line
@@ -68,9 +68,17 @@ let 
    else showWarnings config.warnings baseSystem;



  # Replace runtime dependencies

  system = foldr ({ oldDependency, newDependency }: drv:

      pkgs.replaceDependency { inherit oldDependency newDependency drv; }

    ) baseSystemAssertWarn config.system.replaceRuntimeDependencies;

  system = let replacements = config.system.replaceRuntimeDependencies; in

    if replacements == [] then

      # Avoid IFD if possible, by sidestepping replaceDependencies if no replacements are specified.

      baseSystemAssertWarn

    else

      (pkgs.replaceDependencies.override {

        nix = config.nix.package;

      }) {

        drv = baseSystemAssertWarn;

        inherit replacements;

      };



  systemWithBuildDeps = system.overrideAttrs (o: {

    systemBuildClosure = pkgs.closureInfo { rootPaths = [ system.drvPath ]; };