Fix several compiler warnings, reordering issues,

common/common.H

@@ -60,7 +60,7 @@ public:
 
     std::shared_ptr<T> get_ptr() { return ptr_; };
 
-    bool writeData(Ostream &) const {};
+    bool writeData(Ostream &) const { return false; };
 };
 
 typedef IOPtr<gko::matrix::Coo<scalar>> GKOCOOIOPtr;
@@ -112,6 +112,7 @@ public:
 
     GKO_ENABLE_CRITERION_FACTORY(OpenFOAMStoppingCriterion, parameters,
                                  Factory);
+
     GKO_ENABLE_BUILD_METHOD(Factory);
 
 protected:
@@ -201,10 +202,10 @@ class lduLduCommonBase {
     // should be sorted
     const bool sort_;
 
-    const word app_executor_name_;
-
     const word device_executor_name_;
 
+    const word app_executor_name_;
+
     // if sorting_idxs_ was found in object registry it does not
     // need to be resorted
     mutable bool is_sorted_;
@@ -313,11 +314,11 @@ public:
 
     label maxIter() const { return maxIter_; }
 
-    const label nCells() const { return nCells_; };
+    label nCells() const { return nCells_; };
 
-    const label nElems() const { return nElems_; };
+    label nElems() const { return nElems_; };
 
-    const label nNeighbours() const { return nNeighbours_; };
+    label nNeighbours() const { return nNeighbours_; };
 
     //
     bool get_update_sys_matrix() const { return (update_sysMatrix_ == "yes"); }

lduMatrix/GKOBiCGStab/GKOBiCGStab.H

@@ -61,8 +61,8 @@ public:
         std::vector<std::shared_ptr<const gko::stop::CriterionFactory>>
             criterion_vec) const
     {
-        if (preconditioner_ == "none")
-            return create_default(exec, criterion_vec);
+        // if (preconditioner_ == "none")
+        return create_default(exec, criterion_vec);
     };
 
     std::unique_ptr<gko::solver::Bicgstab<double>::Factory,