nixpkgs/pkgs/stdenv/default.nix

# This file defines the various standard build environments.
#
# On Linux systems, the standard build environment consists of
# Nix-built instances glibc and the `standard' Unix tools, i.e., the
# Posix utilities, the GNU C compiler, and so on.  On other systems,
# we use the native C library.

{ system, allPackages ? import ../.., platform, config, lib }:


rec {


  # The native (i.e., impure) build environment.  This one uses the
  # tools installed on the system outside of the Nix environment,
  # i.e., the stuff in /bin, /usr/bin, etc.  This environment should
  # be used with care, since many Nix packages will not build properly
  # with it (e.g., because they require GNU Make).
  stdenvNative = (import ./native {
    inherit system allPackages config;
  }).stdenv;

  stdenvNativePkgs = allPackages {
    bootStdenv = stdenvNative;
    noSysDirs = false;
  };


  # The Nix build environment.
  stdenvNix = import ./nix {
    inherit config lib;
    stdenv = stdenvNative;
    pkgs = stdenvNativePkgs;
  };

  # Linux standard environment.
  stdenvLinux = (import ./linux { inherit system allPackages platform config lib; }).stdenvLinux;

  # Darwin standard environment.
  stdenvDarwin = (import ./darwin { inherit system allPackages platform config;}).stdenvDarwin;

  # Pure Darwin standard environment. Allows building with the sandbox enabled. To use,
  # you can add this to your nixpkgs config:
  #
  #   replaceStdenv = {pkgs}: pkgs.allStdenvs.stdenvDarwinPure
  stdenvDarwinPure = (import ./pure-darwin { inherit system allPackages platform config;}).stage5;

  # Select the appropriate stdenv for the platform `system'.
  stdenv =
    if system == "i686-linux" then stdenvLinux else
    if system == "x86_64-linux" then stdenvLinux else
    if system == "armv5tel-linux" then stdenvLinux else
    if system == "armv6l-linux" then stdenvLinux else
    if system == "armv7l-linux" then stdenvLinux else
    if system == "mips64el-linux" then stdenvLinux else
    if system == "powerpc-linux" then /* stdenvLinux */ stdenvNative else
    if system == "x86_64-darwin" then stdenvDarwin else
    if system == "x86_64-solaris" then stdenvNix else
    if system == "i686-cygwin" then stdenvNative else
    if system == "x86_64-cygwin" then stdenvNative else
    stdenvNative;
}