Bug in field versioning (in vertical reduction pattern)

[cosunae]

The following example will do versioning of tmp, which will lead to wrong result

stencil stencil {
  storage a, tmp, c;

  Do {
    vertical_region(k_end, k_end)
      tmp=0;

    vertical_region(k_end-1, k_start) {
      a = tmp[k+1];
      tmp = a;
      c = tmp;
    }
  }
};

    struct stage_0_0 {
      using c = gridtools::accessor<0, gridtools::enumtype::inout, gridtools::extent<0, 0, 0, 0, 0, 0>>;
      using tmp = gridtools::accessor<1, gridtools::enumtype::inout, gridtools::extent<0, 0, 0, 0, 0, 0>>;
      using a = gridtools::accessor<2, gridtools::enumtype::inout, gridtools::extent<0, 0, 0, 0, 0, 0>>;
      using tmp_1 = gridtools::accessor<3, gridtools::enumtype::inout, gridtools::extent<0, 0, 0, 0, 0, 1>>;
      using arg_list = boost::mpl::vector<c, tmp, a, tmp_1>;

      template <typename Evaluation>
      GT_FUNCTION static void Do(Evaluation& eval, interval_end_0_end_0) {
        eval(tmp_1(0, 0, 0)) = (int)0;
      }

      template <typename Evaluation>
      GT_FUNCTION static void Do(Evaluation& eval, interval_start_0_end_minus_1) {
        eval(a(0, 0, 0)) = eval(tmp_1(0, 0, 1));
        eval(tmp(0, 0, 0)) = eval(a(0, 0, 0));
        eval(c(0, 0, 0)) = eval(tmp(0, 0, 0));
      }
    };

I guess tmp should not be versioned in this case

[cosunae]

It is somehow working if a is declared locally as a double

[mroethlin]

This is still open as of 17.10.2019 / master: a8ded67, i.e. is still versioned: PASS: PassFieldVersioning: stencil: rename:13 tmp:tmp_0