anchor.diff:  in
   stdenv.mkDerivation rec {
     pname = "openblas";
  -  version = "0.3.13";
  +  version = "0.3.15";
   
     outputs = [ "out" "dev" ];
   
  
positive.code:     owner = "xianyi";
      repo = "OpenBLAS";
      rev = "v${version}";
      sha256 = "14jxh0v3jfbw4mfjx4mcz4dd51lyq7pqvh9k8dg94539ypzjr2lj";
    };
  
    # apply https://github.com/xianyi/OpenBLAS/pull/3060 to fix a crash on arm
    # remove this when updating to 0.3.14 or newer
    patches = [
      (fetchpatch {
        name = "label-get_cpu_ftr-as-volatile.patch";
        url = "https://github.com/xianyi/OpenBLAS/commit/6fe0f1fab9d6a7f46d71d37ebb210fbf56924fbc.diff";
        sha256 = "06gwh73k4sas1ap2fi3jvpifbjkys2vhmnbj4mzrsvj279ljsfdk";
      })
    ];
  
    inherit blas64;
  
  
negative.code: { lib, stdenv, fetchFromGitHub, perl, which
  # Most packages depending on openblas expect integer width to match
  # pointer width, but some expect to use 32-bit integers always
  # (for compatibility with reference BLAS).
  