needing to keep a new tree of expressions apart for the expressions to get
cross-compiled.
I changed the whole way of using cross compilation with nixpkgs, which before
was done through a simple adapter.
Now the adapter became complex, and I've tried to avoid the most obvious
recursivities. For example, the fetchurl expression should
never be cross-compiled, as the gmp, mpfr, and some others, like
some ncurses, perl, ... I made overrided copies of those necessary as
perlNoCross, ncursesNoCross, as stdenvNoCross, keeping in mind that
the stdenv (capable of cross compilation) is built upon stdenvNoCross using
an adapter.
So, to cross compile, instead of building using "nixpkgs/default.nix",
you should build with your
own "myarchiteture.nix", which should have contents like these, for example:
import /etc/nixos/nixpkgs/default.nix
{
crossSystem = {
config = "armv5tel-unknown-linux-gnueabi";
bigEndian = false;
arch = "arm";
float = "soft";
};
}
svn path=/nixpkgs/branches/stdenv-updates/; revision=18398
It still does not work, but I think I already get glibc cross compiled.
Next: gcc and g++, and set some setup script hooks on stdenvCross.
It took quite enough hours for this commit.
svn path=/nixpkgs/branches/stdenv-updates/; revision=18351
My idea is to provide special stdenv expressions that will contain in the path
additional cross compilers. As most expressions for programs accept a stdenv parameter,
we could substitute this parameter with the special stdenv, which will have a
generic builder that attempts the usual "--target=..." and can additionally
have an env variable like "cross" with the target architecture set.
So, finally we could have additional expressions like this:
bashRealArm = makeOverridable (import ../shells/bash) {
inherit fetchurl bison;
stdenv = stdenvCross "armv5tel-unknown-linux-gnueabi";
};
Meanwhile it does not work - I still cannot get the cross-gcc to build.
I think it does not fill the previous expressions with a lot of noise, so I
think it may be a good path to follow.
I only touched some files of the current stdenv: gcc-4.3, kernel headers
2.6.28, glibc 2.9, ...
I tried to use the gcc-cross-wrapper, that may be very outdated. Maybe I will
update it, or update the gcc-wrapper expression to make it fit the cross tools,
but meanwhile I even cannot build gcc, so I have not tested the wrapper.
This new idea on cross compiling is not similar to that of the
nixpkgs/branches/cross-compilation, which mostly added bare new expressions for
anything to be cross compiled, if I understood it correctly.
I cared not to break anything of the usual stdenv in all this work.
svn path=/nixpkgs/branches/stdenv-updates/; revision=18343
