Commit 1d4489dc authored by Yuriy Taraday's avatar Yuriy Taraday
Browse files

stdenv: Replace "// optionalAttrs" with nullable attr name 

As in https://github.com/NixOS/nixpkgs/pull/430132, it saves a lot of
set allocations and merge operations, but makes code harder to read.

I've tried introducing a function like this to make code cleaner, but it
increases number of envs and space taken by them significantly:

  optionalAttr = cond: name: if cond then name else null;

I've also tried applying this logic to the section with isDarwin, but
it makes things measurably worse for x86_64-linux eval.
parent ca22674f

pkgs/stdenv/generic/make-derivation.nix

+45 −40
Original line number Diff line number Diff line
@@ -202,17 +202,15 @@ let 
    # to be built eventually, we would still like to get the error early and without

    # having to wait while nix builds a derivation that might not be used.

    # See also https://github.com/NixOS/nix/issues/4629

    optionalAttrs (attrs ? disallowedReferences) {

      disallowedReferences = map unsafeDerivationToUntrackedOutpath attrs.disallowedReferences;

    }

    // optionalAttrs (attrs ? disallowedRequisites) {

      disallowedRequisites = map unsafeDerivationToUntrackedOutpath attrs.disallowedRequisites;

    }

    // optionalAttrs (attrs ? allowedReferences) {

      allowedReferences = mapNullable unsafeDerivationToUntrackedOutpath attrs.allowedReferences;

    }

    // optionalAttrs (attrs ? allowedRequisites) {

      allowedRequisites = mapNullable unsafeDerivationToUntrackedOutpath attrs.allowedRequisites;

    {

      ${if (attrs ? disallowedReferences) then "disallowedReferences" else null} =

        map unsafeDerivationToUntrackedOutpath attrs.disallowedReferences;

      ${if (attrs ? disallowedRequisites) then "disallowedRequisites" else null} =

        map unsafeDerivationToUntrackedOutpath attrs.disallowedRequisites;

      ${if (attrs ? allowedReferences) then "allowedReferences" else null} =

        mapNullable unsafeDerivationToUntrackedOutpath attrs.allowedReferences;

      ${if (attrs ? allowedRequisites) then "allowedRequisites" else null} =

        mapNullable unsafeDerivationToUntrackedOutpath attrs.allowedRequisites;

    };



  makeDerivationArgument =
@@ -478,8 +476,8 @@ let 


        derivationArg =

          removeAttrs attrs removedOrReplacedAttrNames

          // (optionalAttrs (attrs ? name || (attrs ? pname && attrs ? version)) {

            name =

          // {

            ${if (attrs ? name || (attrs ? pname && attrs ? version)) then "name" else null} =

              let

                # Indicate the host platform of the derivation if cross compiling.

                # Fixed-output derivations like source tarballs shouldn't get a host
@@ -507,8 +505,7 @@ let 
                  ) "The `version` attribute cannot be null.";

                  "${attrs.pname}${staticMarker}${hostSuffix}-${attrs.version}"

              );

          })

          // {



            builder = attrs.realBuilder or stdenv.shell;

            args =

              attrs.args or [
@@ -556,28 +553,33 @@ let 
            inherit doCheck doInstallCheck;



            inherit outputs;

          }

          // optionalAttrs (__contentAddressed) {

            inherit __contentAddressed;

            # Provide default values for outputHashMode and outputHashAlgo because

            # most people won't care about these anyways

            outputHashAlgo = attrs.outputHashAlgo or "sha256";

            outputHashMode = attrs.outputHashMode or "recursive";

          }

          // optionalAttrs (enableParallelBuilding) {

            inherit enableParallelBuilding;

            enableParallelChecking = attrs.enableParallelChecking or true;

            enableParallelInstalling = attrs.enableParallelInstalling or true;

          }

          // optionalAttrs (hardeningDisable != [ ] || hardeningEnable != [ ] || stdenv.hostPlatform.isMusl) {

            NIX_HARDENING_ENABLE = builtins.concatStringsSep " " enabledHardeningOptions;

          }

          //



            # When the derivations is content addressed provide default values

            # for outputHashMode and outputHashAlgo because most people won't

            # care about these anyways

            ${if __contentAddressed then "__contentAddressed" else null} = __contentAddressed;

            ${if __contentAddressed then "outputHashAlgo" else null} = attrs.outputHashAlgo or "sha256";

            ${if __contentAddressed then "outputHashMode" else null} = attrs.outputHashMode or "recursive";



            ${if enableParallelBuilding then "enableParallelBuilding" else null} = enableParallelBuilding;

            ${if enableParallelBuilding then "enableParallelChecking" else null} =

              attrs.enableParallelChecking or true;

            ${if enableParallelBuilding then "enableParallelInstalling" else null} =

              attrs.enableParallelInstalling or true;



            ${

              if (hardeningDisable != [ ] || hardeningEnable != [ ] || stdenv.hostPlatform.isMusl) then

                "NIX_HARDENING_ENABLE"

              else

                null

            } =

              builtins.concatStringsSep " " enabledHardeningOptions;



            # TODO: remove platform condition

            # Enabling this check could be a breaking change as it requires to edit nix.conf

            # NixOS module already sets gccarch, unsure of nix installers and other distributions

            optionalAttrs

              (

            ${

              if

                stdenv.buildPlatform ? gcc.arch

                && !(

                  stdenv.buildPlatform.isAarch64
@@ -589,9 +591,12 @@ let 
                      stdenv.buildPlatform.gcc.arch == "armv8-a"

                  )

                )

              )

              {

                requiredSystemFeatures = attrs.requiredSystemFeatures or [ ] ++ [

              then

                "requiredSystemFeatures"

              else

                null

            } =

              attrs.requiredSystemFeatures or [ ] ++ [

                "gccarch-${stdenv.buildPlatform.gcc.arch}"

              ];

          }