# nixos-unstable
$ git rev-parse HEAD
36fd87baa9083f34f7f5027900b62ee6d09b1f2f
$ nom build -f default.nix pkgsCross.wasi32.buildPackages.libunwind --print-out-paths
Finished at 23:57:40 after 0s
/nix/store/c3m2ib9lpw24r3amxlfqak6bh515kdnq-libunwind-1.8.1

diff --git a/pkgs/development/compilers/rust/rustc.nix b/pkgs/development/compilers/rust/rustc.nix
index d7a1ee625f9c..cf5ab3459894 100644
--- a/pkgs/development/compilers/rust/rustc.nix
+++ b/pkgs/development/compilers/rust/rustc.nix
@@ -360,6 +360,7 @@ stdenv.mkDerivation (finalAttrs: {
         mkdir -p $out/lib
         ln -s ${llvmPackages.libunwind}/lib/libunwind.so $out/lib/libgcc_s.so
         ln -s ${llvmPackages.libunwind}/lib/libunwind.so $out/lib/libgcc_s.so.1
+        ln -s ${llvmPackages.libunwind}/lib/libunwind.so $out/lib/libunwind.so.1
       '')
     ];
 

got past that (I think)

but getting this

wasm32-unknown-wasi-rustc> WARNING: The `change-id` is missing in the `config.toml`. This means that you will not be able to track the major changes made to the bootstrap configurations.
wasm32-unknown-wasi-rustc> NOTE: to silence this warning, add `change-id = 133207` at the top of `config.toml`
wasm32-unknown-wasi-rustc> thread 'main' panicked at src/core/build_steps/compile.rs:389:13:
wasm32-unknown-wasi-rustc> Target "wasm32-wasip1" does not have a "wasi-root" key in Config.toml or `$WASI_SDK_PATH` set
wasm32-unknown-wasi-rustc> note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
wasm32-unknown-wasi-rustc> Build completed unsuccessfully in 0:00:56

don't know much about wasi or cross compilation

In reply to @phanirithvij:matrix.org
😅 I had to sleep

Is this the whole hack?

final: prev: {
  # Setup custom 'wasm32-wasip2' target.
  # Dont touch 'wasi32', since it would trigger a Firefox recompilation.
  pkgsCross = prev.pkgsCross // {
    wasm32-wasip2 = import prev.path {
      inherit (prev) system;

      crossSystem = prev.lib.systems.examples.wasi32 // {
        rust = {
          rustcTarget = "wasm32-wasip2";
        };
      };
    };
  };
}

Is this the whole hack?

final: prev: {
  # Setup custom 'wasm32-wasip2' target.
  # Dont touch 'wasi32', since it would trigger a Firefox recompilation.
  pkgsCross = prev.pkgsCross // {
    wasm32-wasip2 = import prev.path {
      inherit (prev) system;

      crossSystem = prev.lib.systems.examples.wasi32 // {
        rust = {
          rustcTarget = "wasm32-wasip2";
        };
      };
    };
  };
}