anchor.diff:      ${if mpiSupport then "unset CC" else ""}
     '';
   
  -  configureFlags = lib.optional debugEnable "--enable-debug"
  +  configureFlags = [ "--enable-pthread=-pthread" ]
  +    ++ lib.optional debugEnable "--enable-debug"
       ++ lib.optional mpiSupport "--enable-mpi"
     ;
   
     makeFlags = [ "V=0" ];
  +  checkFlags = lib.optional isOpenmpi "-j1";
   
     dontDisableStatic = true;
     enableParallelBuilding = true;
  -  doCheck = stdenv.hostPlatform == stdenv.buildPlatform;
  +  doCheck = !stdenv.isAarch64 && stdenv.hostPlatform == stdenv.buildPlatform;
   
     meta = {
       branch = "prev3-develop";
  
positive.code: { lib, stdenv, fetchFromGitHub
  , autoreconfHook, pkg-config
  , p4est-sc-debugEnable ? true, p4est-sc-mpiSupport ? true
  , mpi, openmpi, openssh, zlib
  }:
  
  let
    dbg = if debugEnable then "-dbg" else "";
    debugEnable = p4est-sc-debugEnable;
    mpiSupport = p4est-sc-mpiSupport;
  in
  stdenv.mkDerivation {
    pname = "p4est-sc${dbg}";
  
negative.code:   nativeBuildInputs = [ autoreconfHook pkg-config ];
    propagatedBuildInputs = [ zlib ]
      ++ lib.optional mpiSupport mpi
      ++ lib.optional isOpenmpi openssh
    ;
    inherit debugEnable mpiSupport;
  
  