Packaging/32bit Applications
Building software with 32bit gcc
Question: I'm invoking gcc with -m32 and it fails to find `gnu/stubs-32.h`
Answer (clever): you want to use pkgsi686Linux
instead of pkgs, so things like pkgsi686Linux.stdenv.mkDerivation
or pkgsi686Linux.callPackage
then nix will give you 32bit everything[1]
Building multilib software
If a package wants to compile both 32/64-bit executable, you need a compiler with multilib support.
Nixpkgs provides multiStdenv.mkDerivation
that should be used instead stdenv.mkDerivation
.
This is equivalent to using gcc-multilib
in debian derivatives.