lean: 3.50.2 -> 3.50.3

stdenv.mkDerivation rec {

  pname = "lean";

  version = "3.50.2";

  version = "3.50.3";

  src = fetchFromGitHub {

    owner  = "leanprover-community";

    # from. this is then used to check whether an olean file should be

    # rebuilt. don't use a tag as rev because this will get replaced into

    # src/githash.h.in in preConfigure.

    rev    = "a4f95b7ef008115baca425f5f0b5c7d0283a80ad";

    sha256 = "sha256-LFCSFmUsiFMrhaETT8+Q3Btba4yc9KR5yQluNzOQOW0=";

    rev    = "855e5b74e3a52a40552e8f067169d747d48743fd";

    sha256 = "sha256-RH4w7PpzC+fhqCHikXQO2pUUvWD2qrA0mVMUGxpauwE=";

  };

  nativeBuildInputs = [ cmake ];