mjlbach: this seems to work:
```nix
self: super:
let
  sources = import ../nix/sources.nix;
  libPath = with super; lib.concatStringsSep ":" [
    "${lib.getLib libgccjit}/lib/gcc/${stdenv.targetPlatform.config}/${libgccjit.version}"
    "${lib.getLib stdenv.cc.cc}/lib"
    "${lib.getLib stdenv.glibc}/lib"
  ];
  emacs-overlay = (import sources.emacs-overlay self super);
in {
  emacsGccWrapped = super.symlinkJoin {
    name = "emacsGccWrapped";
    paths = [ emacs-overlay.emacsGcc ];
    buildInputs = [ super.makeWrapper ];
    postBuild = ''
      wrapProgram $out/bin/emacs \
      --set LIBRARY_PATH ${libPath}
    '';
    meta.platforms = super.stdenv.lib.platforms.linux;

    passthru = {
      nativeComp = true;
      version = emacs-overlay.emacsGcc.version;
      src = emacs-overlay.emacsGcc.src;
    };
  };
} // sources.emacs-overlay
```

Is it at risk of infinite recursions?