fix sysroot resolution

lib/combine.nix

@@ -1,13 +1,25 @@
-{ lib, symlinkJoin }:
+{ lib, symlinkJoin, zlib, stdenv }:
 
 name: paths:
 
 symlinkJoin {
  inherit name paths;
  postBuild = ''
- if [ -d $out/bin ]; then
- cp --remove-destination $(realpath $out/bin/*) $out/bin
- fi
+ for file in $(find $out/bin -xtype f); do
+ install -m755 $(realpath "$file") $out/bin
+
+ ${lib.optionalString stdenv.isLinux ''
+ patchelf --set-rpath $out/lib "$file" || true
+ ''}
+
+ ${lib.optionalString stdenv.isDarwin ''
+ install_name_tool -add_rpath $out/lib "$file" || true
+ ''}
+ done
+
+ for file in $(find $out/lib -name "librustc_driver-*"); do
+ install $(realpath "$file") $out/lib
+ done
  '';
  meta.platforms = lib.platforms.all;
 }