From d8b42a02ec04281832f095c92f182e8b7d4d9aa9 Mon Sep 17 00:00:00 2001
From: Timo Koch <timo.koch@iws.uni-stuttgart.de>
Date: Tue, 31 Mar 2020 15:05:09 +0200
Subject: [PATCH 1/4] [amg] Only construct parallel helper if MPI was found

---
 dumux/linear/amgbackend.hh | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/dumux/linear/amgbackend.hh b/dumux/linear/amgbackend.hh
index 840933a97a..7c49d40d6b 100644
--- a/dumux/linear/amgbackend.hh
+++ b/dumux/linear/amgbackend.hh
@@ -82,8 +82,10 @@ public:
                        const typename LinearSolverTraits::DofMapper& dofMapper,
                        const std::string& paramGroup = "")
     : LinearSolver(paramGroup)
+#if HAVE_MPI
     , phelper_(std::make_shared<ParallelISTLHelper<LinearSolverTraits>>(gridView, dofMapper))
     , isParallel_(Dune::MPIHelper::getCollectiveCommunication().size() > 1)
+#endif
     {
         reset();
     }
@@ -224,9 +226,11 @@ private:
         solver.apply(x, b, result_);
     }
 
+#if HAVE_MPI
     std::shared_ptr<ParallelISTLHelper<LinearSolverTraits>> phelper_;
+#endif
     Dune::InverseOperatorResult result_;
-    bool isParallel_;
+    bool isParallel_ = false;
     bool firstCall_;
 };
 
-- 
GitLab


From ad39cda34df59598dcc21f2a5951811495728a3a Mon Sep 17 00:00:00 2001
From: Timo Koch <timo.koch@iws.uni-stuttgart.de>
Date: Tue, 31 Mar 2020 15:06:29 +0200
Subject: [PATCH 2/4] [istlfactory] Only construct parallel helper if MPI is
 found

---
 dumux/linear/istlsolverfactorybackend.hh | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/dumux/linear/istlsolverfactorybackend.hh b/dumux/linear/istlsolverfactorybackend.hh
index fa96f2e425..71e330eb9c 100644
--- a/dumux/linear/istlsolverfactorybackend.hh
+++ b/dumux/linear/istlsolverfactorybackend.hh
@@ -85,8 +85,10 @@ public:
                              const typename LinearSolverTraits::DofMapper& dofMapper,
                              const std::string& paramGroup = "")
     : paramGroup_(paramGroup)
+#if HAVE_MPI
     , parallelHelper_(std::make_unique<ParallelISTLHelper<LinearSolverTraits>>(gridView, dofMapper))
     , isParallel_(Dune::MPIHelper::getCollectiveCommunication().size() > 1)
+#endif
     {
         reset();
     }
@@ -227,8 +229,10 @@ private:
     }
 
     const std::string paramGroup_;
+#if HAVE_MPI
     std::unique_ptr<ParallelISTLHelper<LinearSolverTraits>> parallelHelper_;
-    bool isParallel_;
+#endif
+    bool isParallel_ = false;
     bool firstCall_;
 
     Dune::InverseOperatorResult result_;
-- 
GitLab


From 942650f5a469a0624364c40838b7d3ce56065a2f Mon Sep 17 00:00:00 2001
From: Timo Koch <timo.koch@iws.uni-stuttgart.de>
Date: Tue, 31 Mar 2020 15:10:19 +0200
Subject: [PATCH 3/4] [linearsolvertraits] Parallel types should only exists if
 MPI is found

---
 dumux/linear/linearsolvertraits.hh | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/dumux/linear/linearsolvertraits.hh b/dumux/linear/linearsolvertraits.hh
index dcca6e0a75..154071021c 100644
--- a/dumux/linear/linearsolvertraits.hh
+++ b/dumux/linear/linearsolvertraits.hh
@@ -125,11 +125,13 @@ struct LinearSolverTraitsBase
     template<class Matrix, class Vector>
     using Sequential = SequentialSolverTraits<Matrix, Vector>;
 
+#if HAVE_MPI
     template<class Matrix, class Vector>
     using ParallelOverlapping = OverlappingSolverTraits<Matrix, Vector>;
 
     template<class Matrix, class Vector>
     using ParallelNonoverlapping = NonoverlappingSolverTraits<Matrix, Vector>;
+#endif
 };
 
 //! Box: use overlapping or non-overlapping model depending on the grid
-- 
GitLab


From 676ac4bc38acd7567d8751b7eea588ee547e4354 Mon Sep 17 00:00:00 2001
From: Timo Koch <timo.koch@iws.uni-stuttgart.de>
Date: Tue, 31 Mar 2020 15:22:17 +0200
Subject: [PATCH 4/4] [amg] Use unique_ptr internally for parallel helper

---
 dumux/linear/amgbackend.hh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/dumux/linear/amgbackend.hh b/dumux/linear/amgbackend.hh
index 7c49d40d6b..9243548481 100644
--- a/dumux/linear/amgbackend.hh
+++ b/dumux/linear/amgbackend.hh
@@ -83,7 +83,7 @@ public:
                        const std::string& paramGroup = "")
     : LinearSolver(paramGroup)
 #if HAVE_MPI
-    , phelper_(std::make_shared<ParallelISTLHelper<LinearSolverTraits>>(gridView, dofMapper))
+    , phelper_(std::make_unique<ParallelISTLHelper<LinearSolverTraits>>(gridView, dofMapper))
     , isParallel_(Dune::MPIHelper::getCollectiveCommunication().size() > 1)
 #endif
     {
@@ -227,7 +227,7 @@ private:
     }
 
 #if HAVE_MPI
-    std::shared_ptr<ParallelISTLHelper<LinearSolverTraits>> phelper_;
+    std::unique_ptr<ParallelISTLHelper<LinearSolverTraits>> phelper_;
 #endif
     Dune::InverseOperatorResult result_;
     bool isParallel_ = false;
-- 
GitLab