From c7c29483e740c9b12475a977e02d70bc265e6cbd Mon Sep 17 00:00:00 2001
From: Arne Morten Kvarving <arne.morten.kvarving@sintef.no>
Date: Tue, 11 May 2021 14:48:50 +0200
Subject: [PATCH] fix regression: unconditional dereferences

equilGrid and equilCartesianMapper can only
be dereferenced on rank 0.
---
 ebos/collecttoiorank.cc  | 14 +++++++-------
 ebos/collecttoiorank.hh  |  4 ++--
 ebos/eclwriter.hh        |  6 ++++--
 tests/test_ecl_output.cc |  4 ++--
 4 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/ebos/collecttoiorank.cc b/ebos/collecttoiorank.cc
index b2c73fcdc..bc5c5ac23 100644
--- a/ebos/collecttoiorank.cc
+++ b/ebos/collecttoiorank.cc
@@ -667,10 +667,10 @@ private:
 
 template <class Grid, class EquilGrid, class GridView>
 CollectDataToIORank<Grid,EquilGrid,GridView>::
-CollectDataToIORank(const Grid& grid, const EquilGrid& equilGrid,
+CollectDataToIORank(const Grid& grid, const EquilGrid* equilGrid,
                     const GridView& localGridView,
                     const Dune::CartesianIndexMapper<Grid>& cartMapper,
-                    const Dune::CartesianIndexMapper<EquilGrid>& equilCartMapper)
+                    const Dune::CartesianIndexMapper<EquilGrid>* equilCartMapper)
     : toIORankComm_()
 {
     // index maps only have to be build when reordering is needed
@@ -701,9 +701,9 @@ CollectDataToIORank(const Grid& grid, const EquilGrid& equilGrid,
             // We need a mapping from local to global grid, here we
             // use equilGrid which represents a view on the global grid
             // reserve memory
-            const size_t globalSize = equilGrid.leafGridView().size(0);
+            const size_t globalSize = equilGrid->leafGridView().size(0);
             globalCartesianIndex_.resize(globalSize, -1);
-            const EquilGridView equilGridView = equilGrid.leafGridView();
+            const EquilGridView equilGridView = equilGrid->leafGridView();
 
             using EquilElementMapper = Dune::MultipleCodimMultipleGeomTypeMapper<EquilGridView>;
             EquilElementMapper equilElemMapper(equilGridView, Dune::mcmgElementLayout());
@@ -713,11 +713,11 @@ CollectDataToIORank(const Grid& grid, const EquilGrid& equilGrid,
             grid.scatterData(handle);
 
             // loop over all elements (global grid) and store Cartesian index
-            auto elemIt = equilGrid.leafGridView().template begin<0>();
-            const auto& elemEndIt = equilGrid.leafGridView().template end<0>();
+            auto elemIt = equilGrid->leafGridView().template begin<0>();
+            const auto& elemEndIt = equilGrid->leafGridView().template end<0>();
             for (; elemIt != elemEndIt; ++elemIt) {
                 int elemIdx = equilElemMapper.index(*elemIt);
-                int cartElemIdx = equilCartMapper.cartesianIndex(elemIdx);
+                int cartElemIdx = equilCartMapper->cartesianIndex(elemIdx);
                 globalCartesianIndex_[elemIdx] = cartElemIdx;
             }
 
diff --git a/ebos/collecttoiorank.hh b/ebos/collecttoiorank.hh
index a74139e86..cb138cd0c 100644
--- a/ebos/collecttoiorank.hh
+++ b/ebos/collecttoiorank.hh
@@ -58,10 +58,10 @@ public:
         !std::is_same<Grid, EquilGrid>::value;
 
     CollectDataToIORank(const Grid& grid,
-                        const EquilGrid& equilGrid,
+                        const EquilGrid* equilGrid,
                         const GridView& gridView,
                         const Dune::CartesianIndexMapper<Grid>& cartMapper,
-                        const Dune::CartesianIndexMapper<EquilGrid>& equilCartMapper);
+                        const Dune::CartesianIndexMapper<EquilGrid>* equilCartMapper);
 
     // gather solution to rank 0 for EclipseWriter
     void collect(const Opm::data::Solution& localCellData,
diff --git a/ebos/eclwriter.hh b/ebos/eclwriter.hh
index 05061d158..2d3f765b2 100644
--- a/ebos/eclwriter.hh
+++ b/ebos/eclwriter.hh
@@ -191,10 +191,12 @@ public:
     EclWriter(Simulator& simulator)
         : simulator_(simulator)
         , collectToIORank_(simulator_.vanguard().grid(),
-                           simulator_.vanguard().equilGrid(),
+                           simulator_.vanguard().grid().comm().rank() == 0 ?
+                           &simulator_.vanguard().equilGrid() : nullptr,
                            simulator_.vanguard().gridView(),
                            simulator_.vanguard().cartesianIndexMapper(),
-                           simulator_.vanguard().equilCartesianIndexMapper())
+                           simulator_.vanguard().grid().comm().rank() == 0 ?
+                           &simulator_.vanguard().equilCartesianIndexMapper() : nullptr)
 
     {
         std::vector<std::size_t> wbp_index_list;
diff --git a/tests/test_ecl_output.cc b/tests/test_ecl_output.cc
index 873765961..17a3cc474 100644
--- a/tests/test_ecl_output.cc
+++ b/tests/test_ecl_output.cc
@@ -151,10 +151,10 @@ BOOST_AUTO_TEST_CASE(Summary)
     using GridView = Opm::GetPropType<TypeTag, Opm::Properties::GridView>;
     using CollectDataToIORankType = Opm::CollectDataToIORank<Grid,EquilGrid,GridView>;
     CollectDataToIORankType collectToIORank(simulator->vanguard().grid(),
-                                            simulator->vanguard().equilGrid(),
+                                            &simulator->vanguard().equilGrid(),
                                             simulator->vanguard().gridView(),
                                             simulator->vanguard().cartesianIndexMapper(),
-                                            simulator->vanguard().equilCartesianIndexMapper());
+                                            &simulator->vanguard().equilCartesianIndexMapper());
     Opm::EclOutputBlackOilModule<TypeTag> eclOutputModule(*simulator, {}, collectToIORank);
 
     typedef Opm::EclWriter<TypeTag> EclWriterType;