Only show/build a package on the platforms listed in meta.platforms

The function ‘mkDerivation’ now checks whether the current platform
type is included in a package's meta.platform field.  If not, it
throws an exception:

  $ nix-build -A linux --argstr system x86_64-darwin
  error: user-thrown exception: the package ‘linux-3.10.15’ is not supported on ‘x86_64-darwin’

These packages also no longer show up in ‘nix-env -qa’ output.  This
means, for instance, that the number of packages shown on
x86_64-freebsd has dropped from 9268 to 4764.

Since meta.platforms was also used to prevent Hydra from building some
packages, there now is a new attribute meta.hydraPlatforms listing the
platforms on which Hydra should build the package (which defaults to
meta.platforms).

1 files changed, 2 insertions, 0 deletions

diff --git a/pkgs/stdenv/generic/default.nix b/pkgs/stdenv/generic/default.nix
index 083a71548b9..fcd7439e97e 100644
--- a/pkgs/stdenv/generic/default.nix
+++ b/pkgs/stdenv/generic/default.nix
@@ -55,6 +55,8 @@ let
             throw "package ‘${attrs.name}’ has an unfree license, refusing to evaluate"
           else if !allowBroken && attrs.meta.broken or false then
             throw "you can't use package ‘${attrs.name}’ because it has been marked as broken"
+          else if !allowBroken && attrs.meta.platforms or null != null && !lib.lists.elem result.system attrs.meta.platforms then
+            throw "the package ‘${attrs.name}’ is not supported on ‘${result.system}’"
           else
             lib.addPassthru (derivation (
               (removeAttrs attrs ["meta" "passthru" "crossAttrs"])