nixpkgs/pkgs/stdenv/cross/default.nix
John Ericson 5eaea6cee0 cross stdenv: let build package's build deps resolve to native packages
This fixes the "sliding window" principle:
  0. Run packages:       build = native;  host = foreign; target = foreign;
  1. Build packages:     build = native;  host = native;  target = foreign;
  2. Vanilla packages:   build = native;  host = native;  target = native;
  3. Vanilla packages:   build = native;  host = native;  target = native;
  n+3. ...

Each stage's build dependencies are resolved against the previous stage,
and the "foreigns" are shifted accordingly. Vanilla packages alone are
built against themsevles, since there are no more "foreign"s to shift away.

Before, build packages' build dependencies were resolved against
themselves:
  0. Run packages:       build = native;  host = foreign; target = foreign;
  1. Build packages:     build = native;  host = native;  target = foreign;
  2. Build packages:     build = native;  host = native;  target = foreign;
  n+2. ...

This is wrong because that principle is violated by the target
platform staying foreign.

This will change the hashes of many build packages and run packages, but
that is OK. This is an unavoidable cost of fixing cross compiling.

The cross compilation docs have been updated to reflect this fix.
2017-02-05 12:01:53 -05:00

51 lines
1.4 KiB
Nix

{ lib
, localSystem, crossSystem, config, overlays
}:
let
bootStages = import ../. {
inherit lib localSystem overlays;
crossSystem = null;
# Ignore custom stdenvs when cross compiling for compatability
config = builtins.removeAttrs config [ "replaceStdenv" ];
};
in bootStages ++ [
# Build Packages
(vanillaPackages: {
buildPlatform = localSystem;
hostPlatform = localSystem;
targetPlatform = crossSystem;
inherit config overlays;
selfBuild = false;
# It's OK to change the built-time dependencies
allowCustomOverrides = true;
stdenv = vanillaPackages.stdenv // {
overrides = _: _: {};
};
})
# Run Packages
(buildPackages: {
buildPlatform = localSystem;
hostPlatform = crossSystem;
targetPlatform = crossSystem;
inherit config overlays;
selfBuild = false;
stdenv = if crossSystem.useiOSCross or false
then let
inherit (buildPackages.darwin.ios-cross {
prefix = crossSystem.config;
inherit (crossSystem) arch;
simulator = crossSystem.isiPhoneSimulator or false; })
cc binutils;
in buildPackages.makeStdenvCross
buildPackages.stdenv crossSystem
binutils cc
else buildPackages.makeStdenvCross
buildPackages.stdenv crossSystem
buildPackages.binutilsCross buildPackages.gccCrossStageFinal;
})
]