How to build xtensa toolchain (GIT8266O-878)

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Issue or Suggestion Description

If the provided toolchain is quite different from the usual one found in linux distributions, I want to ask how to build it, since what is provided are only some binaries.

https://github.com/espressif/ESP8266_RTOS_SDK?tab=readme-ov-file#get-toolchain

In the case of the toolchain, after a bit more digging, it seems to work with an older gcc toolchain as well, so for anyone needing it, here is a nix shell that will get you there:

let

  pkgs =
    import
      (fetchTarball "https://github.com/NixOS/nixpkgs/archive/b134951a4c9f3c995fd7be05f3243f8ecd65d798.tar.gz")
      { };

in

pkgs.mkShell {
  buildInputs = with pkgs; [
    gcc48
    python2
  ];

  shellHook = ''
    export PATH=${pkgs.gcc48}/bin:$PATH
  '';
}