anchor.diff:      rev = "v${version}";
       sha256 = "0hiap5i9ik6xpvl721n2slanlqygagc1pg2bcjb27ans6balhsfh";
     };
  +
  +  passthru = { inherit (blas) isILP64; };
  +
  +  # Required to activate ILP64.
  +  # See https://github.com/Reference-ScaLAPACK/scalapack/pull/19
  +  postPatch = lib.optionalString passthru.isILP64 ''
  +    sed -i 's/INTSZ = 4/INTSZ = 8/g'   TESTING/EIG/* TESTING/LIN/*
  +    sed -i 's/INTGSZ = 4/INTGSZ = 8/g' TESTING/EIG/* TESTING/LIN/*
  +
  +    # These tests are not adapted to ILP64
  +    sed -i '/xssep/d;/xsgsep/d;/xssyevr/d' TESTING/CMakeLists.txt
  +  '';
   
     nativeBuildInputs = [ cmake ];
     checkInputs = [ openssh ];
  
positive.code:     platforms = [ "x86_64-linux" ];
      maintainers = with maintainers; [ costrouc markuskowa ];
    };
  
  }
  
negative.code: , mpi, blas, lapack
  } :
  
  assert blas.isILP64 == lapack.isILP64;
  
  stdenv.mkDerivation rec {
    pname = "scalapack";
  