diff --git a/Grid/algorithms/CoarsenedMatrix.h b/Grid/algorithms/CoarsenedMatrix.h
index 2fd187ff..a9a82f34 100644
--- a/Grid/algorithms/CoarsenedMatrix.h
+++ b/Grid/algorithms/CoarsenedMatrix.h
@@ -358,7 +358,7 @@ public:
     autoView( in_v , in, AcceleratorRead);
     autoView( out_v , out, AcceleratorWrite);
     autoView( Stencil_v  , Stencil, AcceleratorRead);
-    auto& geom_v = geom;
+    int npoint = geom.npoint;
     typedef LatticeView<Cobj> Aview;
       
     Vector<Aview> AcceleratorViewContainer;
@@ -380,7 +380,7 @@ public:
       int ptype;
       StencilEntry *SE;
 
-      for(int point=0;point<geom_v.npoint;point++){
+      for(int point=0;point<npoint;point++){
 
 	SE=Stencil_v.GetEntry(ptype,point,ss);
 	  
@@ -424,7 +424,7 @@ public:
     autoView( in_v , in, AcceleratorRead);
     autoView( out_v , out, AcceleratorWrite);
     autoView( Stencil_v  , Stencil, AcceleratorRead);
-    auto& geom_v = geom;
+    int npoint = geom.npoint;
     typedef LatticeView<Cobj> Aview;
 
     Vector<Aview> AcceleratorViewContainer;
@@ -454,7 +454,7 @@ public:
       int ptype;
       StencilEntry *SE;
 
-      for(int p=0;p<geom_v.npoint;p++){
+      for(int p=0;p<npoint;p++){
         int point = points_p[p];
 
 	SE=Stencil_v.GetEntry(ptype,point,ss);
diff --git a/Grid/algorithms/LinearOperator.h b/Grid/algorithms/LinearOperator.h
index e1077850..b1cf4d97 100644
--- a/Grid/algorithms/LinearOperator.h
+++ b/Grid/algorithms/LinearOperator.h
@@ -508,7 +508,7 @@ class SchurStaggeredOperator :  public SchurOperatorBase<Field> {
   virtual  void MpcDag   (const Field &in, Field &out){
     Mpc(in,out);
   }
-  virtual void MpcDagMpc(const Field &in, Field &out,RealD &ni,RealD &no) {
+  virtual void MpcDagMpc(const Field &in, Field &out) {
     assert(0);// Never need with staggered
   }
 };
@@ -586,6 +586,7 @@ class HermOpOperatorFunction : public OperatorFunction<Field> {
 template<typename Field>
 class PlainHermOp : public LinearFunction<Field> {
 public:
+  using LinearFunction<Field>::operator();
   LinearOperatorBase<Field> &_Linop;
       
   PlainHermOp(LinearOperatorBase<Field>& linop) : _Linop(linop) 
@@ -599,6 +600,7 @@ public:
 template<typename Field>
 class FunctionHermOp : public LinearFunction<Field> {
 public:
+  using LinearFunction<Field>::operator(); 
   OperatorFunction<Field>   & _poly;
   LinearOperatorBase<Field> &_Linop;
       
diff --git a/Grid/algorithms/Preconditioner.h b/Grid/algorithms/Preconditioner.h
index 65ac3cf9..a95dad7c 100644
--- a/Grid/algorithms/Preconditioner.h
+++ b/Grid/algorithms/Preconditioner.h
@@ -30,13 +30,19 @@ Author: Azusa Yamaguchi <ayamaguc@staffmail.ed.ac.uk>
 
 NAMESPACE_BEGIN(Grid);
 
-template<class Field> class Preconditioner :  public LinearFunction<Field> { 
+template<class Field> using Preconditioner =  LinearFunction<Field> ;
+
+/*
+template<class Field> class Preconditioner :  public LinearFunction<Field> {
+  using LinearFunction<Field>::operator();
   virtual void operator()(const Field &src, Field & psi)=0;
 };
+*/
 
 template<class Field> class TrivialPrecon :  public Preconditioner<Field> { 
 public:
-  void operator()(const Field &src, Field & psi){
+  using Preconditioner<Field>::operator();
+  virtual void operator()(const Field &src, Field & psi){
     psi = src;
   }
   TrivialPrecon(void){};
diff --git a/Grid/algorithms/iterative/BiCGSTABMixedPrec.h b/Grid/algorithms/iterative/BiCGSTABMixedPrec.h
index d9b2a9d7..c34035a8 100644
--- a/Grid/algorithms/iterative/BiCGSTABMixedPrec.h
+++ b/Grid/algorithms/iterative/BiCGSTABMixedPrec.h
@@ -36,7 +36,8 @@ NAMESPACE_BEGIN(Grid);
 template<class FieldD, class FieldF, typename std::enable_if< getPrecision<FieldD>::value == 2, int>::type = 0, typename std::enable_if< getPrecision<FieldF>::value == 1, int>::type = 0> 
 class MixedPrecisionBiCGSTAB : public LinearFunction<FieldD> 
 {
-  public:                                                
+  public:
+    using LinearFunction<FieldD>::operator();
     RealD   Tolerance;
     RealD   InnerTolerance; // Initial tolerance for inner CG. Defaults to Tolerance but can be changed
     Integer MaxInnerIterations;
diff --git a/Grid/algorithms/iterative/LocalCoherenceLanczos.h b/Grid/algorithms/iterative/LocalCoherenceLanczos.h
index 9c945565..dc82134a 100644
--- a/Grid/algorithms/iterative/LocalCoherenceLanczos.h
+++ b/Grid/algorithms/iterative/LocalCoherenceLanczos.h
@@ -67,6 +67,7 @@ public:
 template<class Fobj,class CComplex,int nbasis>
 class ProjectedHermOp : public LinearFunction<Lattice<iVector<CComplex,nbasis > > > {
 public:
+  using LinearFunction<Lattice<iVector<CComplex,nbasis > > >::operator();
   typedef iVector<CComplex,nbasis >           CoarseSiteVector;
   typedef Lattice<CoarseSiteVector>           CoarseField;
   typedef Lattice<CComplex>   CoarseScalar; // used for inner products on fine field
@@ -97,6 +98,7 @@ public:
 template<class Fobj,class CComplex,int nbasis>
 class ProjectedFunctionHermOp : public LinearFunction<Lattice<iVector<CComplex,nbasis > > > {
 public:
+  using LinearFunction<Lattice<iVector<CComplex,nbasis > > >::operator();
   typedef iVector<CComplex,nbasis >           CoarseSiteVector;
   typedef Lattice<CoarseSiteVector>           CoarseField;
   typedef Lattice<CComplex>   CoarseScalar; // used for inner products on fine field
diff --git a/Grid/algorithms/iterative/PrecGeneralisedConjugateResidual.h b/Grid/algorithms/iterative/PrecGeneralisedConjugateResidual.h
index bf454ade..feceb21f 100644
--- a/Grid/algorithms/iterative/PrecGeneralisedConjugateResidual.h
+++ b/Grid/algorithms/iterative/PrecGeneralisedConjugateResidual.h
@@ -43,7 +43,7 @@ NAMESPACE_BEGIN(Grid);
 template<class Field>
 class PrecGeneralisedConjugateResidual : public LinearFunction<Field> {
 public:                                                
-
+  using LinearFunction<Field>::operator();
   RealD   Tolerance;
   Integer MaxIterations;
   int verbose;
diff --git a/Grid/algorithms/iterative/PrecGeneralisedConjugateResidualNonHermitian.h b/Grid/algorithms/iterative/PrecGeneralisedConjugateResidualNonHermitian.h
index 22b7725e..181df320 100644
--- a/Grid/algorithms/iterative/PrecGeneralisedConjugateResidualNonHermitian.h
+++ b/Grid/algorithms/iterative/PrecGeneralisedConjugateResidualNonHermitian.h
@@ -43,7 +43,7 @@ NAMESPACE_BEGIN(Grid);
 template<class Field>
 class PrecGeneralisedConjugateResidualNonHermitian : public LinearFunction<Field> {
 public:                                                
-
+  using LinearFunction<Field>::operator();
   RealD   Tolerance;
   Integer MaxIterations;
   int verbose;
@@ -119,7 +119,8 @@ public:
   RealD GCRnStep(const Field &src, Field &psi,RealD rsq){
 
     RealD cp;
-    ComplexD a, b, zAz;
+    ComplexD a, b;
+    //    ComplexD zAz;
     RealD zAAz;
     ComplexD rq;
 
@@ -146,7 +147,7 @@ public:
     //////////////////////////////////
     MatTimer.Start();
     Linop.Op(psi,Az);
-    zAz = innerProduct(Az,psi);
+    //    zAz = innerProduct(Az,psi);
     zAAz= norm2(Az);
     MatTimer.Stop();
     
@@ -170,7 +171,7 @@ public:
 
     LinalgTimer.Start();
 
-    zAz = innerProduct(Az,psi);
+    //    zAz = innerProduct(Az,psi);
     zAAz= norm2(Az);
 
     //p[0],q[0],qq[0] 
@@ -212,7 +213,7 @@ public:
       MatTimer.Start();
       Linop.Op(z,Az);
       MatTimer.Stop();
-      zAz = innerProduct(Az,psi);
+      //      zAz = innerProduct(Az,psi);
       zAAz= norm2(Az);
 
       LinalgTimer.Start();
diff --git a/Grid/tensors/Tensor_traits.h b/Grid/tensors/Tensor_traits.h
index dfa3c043..89290214 100644
--- a/Grid/tensors/Tensor_traits.h
+++ b/Grid/tensors/Tensor_traits.h
@@ -47,20 +47,20 @@ NAMESPACE_BEGIN(Grid);
   class TypePair {
   public:
     T _internal[2];
-    TypePair<T>& operator=(const Grid::Zero& o) {
+    accelerator TypePair<T>& operator=(const Grid::Zero& o) {
       _internal[0] = Zero();
       _internal[1] = Zero();
       return *this;
     }
 
-    TypePair<T> operator+(const TypePair<T>& o) const {
+    accelerator TypePair<T> operator+(const TypePair<T>& o) const {
       TypePair<T> r;
       r._internal[0] = _internal[0] + o._internal[0];
       r._internal[1] = _internal[1] + o._internal[1];
       return r;
     }
 
-    TypePair<T>& operator+=(const TypePair<T>& o) {
+    accelerator TypePair<T>& operator+=(const TypePair<T>& o) {
       _internal[0] += o._internal[0];
       _internal[1] += o._internal[1];
       return *this;
diff --git a/examples/Example_Laplacian_solver.cc b/examples/Example_Laplacian_solver.cc
index 4dc00280..9a584c0f 100644
--- a/examples/Example_Laplacian_solver.cc
+++ b/examples/Example_Laplacian_solver.cc
@@ -4,7 +4,7 @@ using namespace Grid;
 template<class Field>
 void SimpleConjugateGradient(LinearOperatorBase<Field> &HPDop,const Field &b, Field &x)
 {
-    RealD cp, c, alpha, d, beta, ssq, qq;
+    RealD cp, c, alpha, d, beta, ssq;
     RealD Tolerance=1.0e-10;
     int MaxIterations=10000;
     
diff --git a/tests/core/Test_contfrac_even_odd.cc b/tests/core/Test_contfrac_even_odd.cc
index 53d00010..42bfe361 100644
--- a/tests/core/Test_contfrac_even_odd.cc
+++ b/tests/core/Test_contfrac_even_odd.cc
@@ -235,7 +235,6 @@ void  TestWhat(What & Ddwf,
   pickCheckerboard(Odd ,chi_o,chi);
   pickCheckerboard(Even,phi_e,phi);
   pickCheckerboard(Odd ,phi_o,phi);
-  RealD t1,t2;
 
   SchurDiagMooeeOperator<What,LatticeFermion> HermOpEO(Ddwf);
   HermOpEO.MpcDagMpc(chi_e,dchi_e);
diff --git a/tests/core/Test_dwf_eofa_even_odd.cc b/tests/core/Test_dwf_eofa_even_odd.cc
index 64701069..7812ebb8 100644
--- a/tests/core/Test_dwf_eofa_even_odd.cc
+++ b/tests/core/Test_dwf_eofa_even_odd.cc
@@ -215,7 +215,6 @@ int main (int argc, char ** argv)
     pickCheckerboard(Odd , chi_o, chi);
     pickCheckerboard(Even, phi_e, phi);
     pickCheckerboard(Odd , phi_o, phi);
-    RealD t1,t2;
 
     SchurDiagMooeeOperator<DomainWallEOFAFermionR,LatticeFermion> HermOpEO(Ddwf);
     HermOpEO.MpcDagMpc(chi_e, dchi_e);
diff --git a/tests/core/Test_dwf_even_odd.cc b/tests/core/Test_dwf_even_odd.cc
index 4918f02a..924eb3b7 100644
--- a/tests/core/Test_dwf_even_odd.cc
+++ b/tests/core/Test_dwf_even_odd.cc
@@ -212,8 +212,6 @@ int main (int argc, char ** argv)
   pickCheckerboard(Odd ,chi_o,chi);
   pickCheckerboard(Even,phi_e,phi);
   pickCheckerboard(Odd ,phi_o,phi);
-  RealD t1,t2;
-
 
   SchurDiagMooeeOperator<DomainWallFermionR,LatticeFermion> HermOpEO(Ddwf);
   HermOpEO.MpcDagMpc(chi_e,dchi_e);
diff --git a/tests/core/Test_gamma.cc b/tests/core/Test_gamma.cc
index 2658f2c1..e52049fe 100644
--- a/tests/core/Test_gamma.cc
+++ b/tests/core/Test_gamma.cc
@@ -181,8 +181,8 @@ void checkAdj(const Gamma::Algebra a)
 
 void checkProject(GridSerialRNG &rng)
 {
-  SpinVector     rv, recon, full;
-  HalfSpinVector hsp, hsm;
+  SpinVector     rv, recon;
+  HalfSpinVector hsm;
   
   random(rng, rv);
   
diff --git a/tests/core/Test_gpwilson_even_odd.cc b/tests/core/Test_gpwilson_even_odd.cc
index 69ace859..d510657e 100644
--- a/tests/core/Test_gpwilson_even_odd.cc
+++ b/tests/core/Test_gpwilson_even_odd.cc
@@ -198,7 +198,6 @@ int main (int argc, char ** argv)
   pickCheckerboard(Odd ,chi_o,chi);
   pickCheckerboard(Even,phi_e,phi);
   pickCheckerboard(Odd ,phi_o,phi);
-  RealD t1,t2;
 
   SchurDiagMooeeOperator<GparityWilsonFermionR,FermionField> HermOpEO(Dw);
   HermOpEO.MpcDagMpc(chi_e,dchi_e);
diff --git a/tests/core/Test_main.cc b/tests/core/Test_main.cc
index 6e316aa6..25d840a6 100644
--- a/tests/core/Test_main.cc
+++ b/tests/core/Test_main.cc
@@ -364,14 +364,12 @@ int main(int argc, char **argv) {
 
       {  // Peek-ology and Poke-ology, with a little app-ology
         Complex c;
-        ColourMatrix c_m;
-        SpinMatrix s_m;
-        SpinColourMatrix sc_m;
+        ColourMatrix c_m = Zero();
+        SpinMatrix s_m = Zero();
+        SpinColourMatrix sc_m = Zero();
 
-        s_m = TensorIndexRecursion<ColourIndex>::traceIndex(
-            sc_m);  // Map to traceColour
-        c_m = TensorIndexRecursion<SpinIndex>::traceIndex(
-            sc_m);  // map to traceSpin
+        s_m = TensorIndexRecursion<ColourIndex>::traceIndex(sc_m);  // Map to traceColour
+        c_m = TensorIndexRecursion<SpinIndex>::traceIndex(sc_m);  // map to traceSpin
 
         c = TensorIndexRecursion<SpinIndex>::traceIndex(s_m);
         c = TensorIndexRecursion<ColourIndex>::traceIndex(c_m);
diff --git a/tests/core/Test_mobius_eofa_even_odd.cc b/tests/core/Test_mobius_eofa_even_odd.cc
index 7339f156..68ffe624 100644
--- a/tests/core/Test_mobius_eofa_even_odd.cc
+++ b/tests/core/Test_mobius_eofa_even_odd.cc
@@ -217,7 +217,6 @@ int main (int argc, char ** argv)
     pickCheckerboard(Odd , chi_o, chi);
     pickCheckerboard(Even, phi_e, phi);
     pickCheckerboard(Odd , phi_o, phi);
-    RealD t1,t2;
 
     SchurDiagMooeeOperator<MobiusEOFAFermionR,LatticeFermion> HermOpEO(Ddwf);
     HermOpEO.MpcDagMpc(chi_e, dchi_e);
diff --git a/tests/core/Test_mobius_even_odd.cc b/tests/core/Test_mobius_even_odd.cc
index 7f808cac..e210f236 100644
--- a/tests/core/Test_mobius_even_odd.cc
+++ b/tests/core/Test_mobius_even_odd.cc
@@ -262,7 +262,6 @@ int main (int argc, char ** argv)
   pickCheckerboard(Odd ,chi_o,chi);
   pickCheckerboard(Even,phi_e,phi);
   pickCheckerboard(Odd ,phi_o,phi);
-  RealD t1,t2;
 
 
   SchurDiagMooeeOperator<MobiusFermionR,LatticeFermion> HermOpEO(Ddwf);
diff --git a/tests/core/Test_staggered.cc b/tests/core/Test_staggered.cc
index 51f92993..ba615ad2 100644
--- a/tests/core/Test_staggered.cc
+++ b/tests/core/Test_staggered.cc
@@ -144,7 +144,7 @@ int main (int argc, char ** argv)
     Ds.Dhop(src,result,0);
   }
   double t1=usecond();
-  double t2;
+
   double flops=(16*(3*(6+8+8)) + 15*3*2)*volume*ncall; // == 66*16 +  == 1146
   
   std::cout<<GridLogMessage << "Called Ds"<<std::endl;
diff --git a/tests/core/Test_staggered5D.cc b/tests/core/Test_staggered5D.cc
index 6ab15873..b1b3be1d 100644
--- a/tests/core/Test_staggered5D.cc
+++ b/tests/core/Test_staggered5D.cc
@@ -162,7 +162,6 @@ int main (int argc, char ** argv)
   }
   double t1=usecond();
 
-  double t2;
   double flops=(16*(3*(6+8+8)) + 15*3*2)*volume*ncall; // == 66*16 +  == 1146
   
   std::cout<<GridLogMessage << "Called Ds"<<std::endl;
diff --git a/tests/core/Test_staggered_naive.cc b/tests/core/Test_staggered_naive.cc
index f41d723d..d8ca9d5f 100644
--- a/tests/core/Test_staggered_naive.cc
+++ b/tests/core/Test_staggered_naive.cc
@@ -30,7 +30,6 @@ Author: paboyle <paboyle@ph.ed.ac.uk>
 
 using namespace std;
 using namespace Grid;
- ;
 
 int main (int argc, char ** argv)
 {
@@ -135,7 +134,6 @@ int main (int argc, char ** argv)
     Ds.Dhop(src,result,0);
   }
   double t1=usecond();
-  double t2;
   double flops=(16*(3*(6+8+8)) + 15*3*2)*volume*ncall; // == 66*16 +  == 1146
   
   std::cout<<GridLogMessage << "Called Ds"<<std::endl;
diff --git a/tests/core/Test_wilson_even_odd.cc b/tests/core/Test_wilson_even_odd.cc
index e7733a79..4d240b80 100644
--- a/tests/core/Test_wilson_even_odd.cc
+++ b/tests/core/Test_wilson_even_odd.cc
@@ -204,7 +204,6 @@ int main (int argc, char ** argv)
   pickCheckerboard(Odd ,chi_o,chi);
   pickCheckerboard(Even,phi_e,phi);
   pickCheckerboard(Odd ,phi_o,phi);
-  RealD t1,t2;
 
   SchurDiagMooeeOperator<WilsonFermionR,LatticeFermion> HermOpEO(Dw);
   HermOpEO.MpcDagMpc(chi_e,dchi_e);
diff --git a/tests/core/Test_wilson_twisted_mass_even_odd.cc b/tests/core/Test_wilson_twisted_mass_even_odd.cc
index e0f73456..d9e798c3 100644
--- a/tests/core/Test_wilson_twisted_mass_even_odd.cc
+++ b/tests/core/Test_wilson_twisted_mass_even_odd.cc
@@ -205,7 +205,6 @@ int main (int argc, char ** argv)
   pickCheckerboard(Odd ,chi_o,chi);
   pickCheckerboard(Even,phi_e,phi);
   pickCheckerboard(Odd ,phi_o,phi);
-  RealD t1,t2;
 
   SchurDiagMooeeOperator<WilsonTMFermionR,LatticeFermion> HermOpEO(Dw);
   HermOpEO.MpcDagMpc(chi_e,dchi_e);
diff --git a/tests/core/Test_zmobius_even_odd.cc b/tests/core/Test_zmobius_even_odd.cc
index a52e9bc2..f6e18934 100644
--- a/tests/core/Test_zmobius_even_odd.cc
+++ b/tests/core/Test_zmobius_even_odd.cc
@@ -276,7 +276,6 @@ int main (int argc, char ** argv)
   pickCheckerboard(Odd ,chi_o,chi);
   pickCheckerboard(Even,phi_e,phi);
   pickCheckerboard(Odd ,phi_o,phi);
-  RealD t1,t2;
 
 
   SchurDiagMooeeOperator<ZMobiusFermionR,LatticeFermion> HermOpEO(Ddwf);
diff --git a/tests/forces/Test_rect_force.cc b/tests/forces/Test_rect_force.cc
index c9326f8d..e40cb5fd 100644
--- a/tests/forces/Test_rect_force.cc
+++ b/tests/forces/Test_rect_force.cc
@@ -57,7 +57,6 @@ int main (int argc, char ** argv)
   SU<Nc>::HotConfiguration(pRNG,U);
   
   double beta = 1.0;
-  double c1   = -0.331;
 
   IwasakiGaugeActionR Action(beta);
   //  PlaqPlusRectangleActionR Action(beta,c1);
diff --git a/tests/lanczos/Test_dwf_compressed_lanczos_reorg_synthetic.cc b/tests/lanczos/Test_dwf_compressed_lanczos_reorg_synthetic.cc
index 3766e069..f3cb567c 100644
--- a/tests/lanczos/Test_dwf_compressed_lanczos_reorg_synthetic.cc
+++ b/tests/lanczos/Test_dwf_compressed_lanczos_reorg_synthetic.cc
@@ -40,6 +40,7 @@ using namespace Grid;
 template<class Fobj,class CComplex,int nbasis>
 class ProjectedHermOp : public LinearFunction<Lattice<iVector<CComplex,nbasis > > > {
 public:
+  using LinearFunction<Lattice<iVector<CComplex,nbasis > > >::operator();
   typedef iVector<CComplex,nbasis >           CoarseSiteVector;
   typedef Lattice<CoarseSiteVector>           CoarseField;
   typedef Lattice<CComplex>   CoarseScalar; // used for inner products on fine field
@@ -67,6 +68,8 @@ public:
 template<class Fobj,class CComplex,int nbasis>
 class ProjectedFunctionHermOp : public LinearFunction<Lattice<iVector<CComplex,nbasis > > > {
 public:
+  using LinearFunction<Lattice<iVector<CComplex,nbasis > > >::operator ();
+  
   typedef iVector<CComplex,nbasis >           CoarseSiteVector;
   typedef Lattice<CoarseSiteVector>           CoarseField;
   typedef Lattice<CComplex>   CoarseScalar; // used for inner products on fine field
diff --git a/tests/solver/Test_dwf_hdcr.cc b/tests/solver/Test_dwf_hdcr.cc
index f68e99ab..ba77dffa 100644
--- a/tests/solver/Test_dwf_hdcr.cc
+++ b/tests/solver/Test_dwf_hdcr.cc
@@ -55,6 +55,7 @@ RealD InverseApproximation(RealD x){
 template<class Field,class Matrix> class ChebyshevSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & _SmootherMatrix;
   FineOperator   & _SmootherOperator;
@@ -78,6 +79,7 @@ public:
 template<class Field,class Matrix> class MirsSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & SmootherMatrix;
   FineOperator   & SmootherOperator;
@@ -108,6 +110,7 @@ public:
 template<class Fobj,class CComplex,int nbasis, class Matrix, class Guesser, class CoarseSolver>
 class MultiGridPreconditioner : public LinearFunction< Lattice<Fobj> > {
 public:
+  using LinearFunction<Lattice<Fobj> >::operator();
 
   typedef Aggregation<Fobj,CComplex,nbasis> Aggregates;
   typedef CoarsenedMatrix<Fobj,CComplex,nbasis> CoarseOperator;
diff --git a/tests/solver/Test_dwf_hdcr_16_rb.cc b/tests/solver/Test_dwf_hdcr_16_rb.cc
index b7900b04..4682272d 100644
--- a/tests/solver/Test_dwf_hdcr_16_rb.cc
+++ b/tests/solver/Test_dwf_hdcr_16_rb.cc
@@ -56,9 +56,9 @@ template<class Field> class SolverWrapper : public LinearFunction<Field> {
 private:
   CheckerBoardedSparseMatrixBase<Field> & _Matrix;
   SchurRedBlackBase<Field> & _Solver;
-public:
-
-  /////////////////////////////////////////////////////
+public: 
+  using LinearFunction<Field>::operator();
+ /////////////////////////////////////////////////////
   // Wrap the usual normal equations trick
   /////////////////////////////////////////////////////
   SolverWrapper(CheckerBoardedSparseMatrixBase<Field> &Matrix,
@@ -75,6 +75,7 @@ public:
 template<class Field,class Matrix> class ChebyshevSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & _SmootherMatrix;
   FineOperator   & _SmootherOperator;
@@ -98,6 +99,7 @@ public:
 template<class Field,class Matrix> class MirsSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & SmootherMatrix;
   FineOperator   & SmootherOperator;
@@ -128,6 +130,7 @@ public:
 template<class Fobj,class CComplex,int nbasis, class Matrix, class Guesser, class CoarseSolver>
 class MultiGridPreconditioner : public LinearFunction< Lattice<Fobj> > {
 public:
+  using LinearFunction<Lattice<Fobj> >::operator();
 
   typedef Aggregation<Fobj,CComplex,nbasis> Aggregates;
   typedef CoarsenedMatrix<Fobj,CComplex,nbasis> CoarseOperator;
diff --git a/tests/solver/Test_dwf_hdcr_24_regression.cc b/tests/solver/Test_dwf_hdcr_24_regression.cc
index 180b2e00..e6363474 100644
--- a/tests/solver/Test_dwf_hdcr_24_regression.cc
+++ b/tests/solver/Test_dwf_hdcr_24_regression.cc
@@ -55,6 +55,7 @@ RealD InverseApproximation(RealD x){
 template<class Field,class Matrix> class ChebyshevSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & _SmootherMatrix;
   FineOperator   & _SmootherOperator;
@@ -78,6 +79,7 @@ public:
 template<class Field,class Matrix> class MirsSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & SmootherMatrix;
   FineOperator   & SmootherOperator;
@@ -108,6 +110,8 @@ public:
 template<class Fobj,class CComplex,int nbasis, class Matrix, class Guesser, class CoarseSolver>
 class MultiGridPreconditioner : public LinearFunction< Lattice<Fobj> > {
 public:
+  
+  using LinearFunction<Lattice<Fobj> >::operator();
 
   typedef Aggregation<Fobj,CComplex,nbasis> Aggregates;
   typedef CoarsenedMatrix<Fobj,CComplex,nbasis> CoarseOperator;
diff --git a/tests/solver/Test_dwf_hdcr_2level.cc b/tests/solver/Test_dwf_hdcr_2level.cc
index 4fa1e302..819f3464 100644
--- a/tests/solver/Test_dwf_hdcr_2level.cc
+++ b/tests/solver/Test_dwf_hdcr_2level.cc
@@ -56,6 +56,7 @@ RealD InverseApproximation(RealD x){
 template<class Field,class Matrix> class ChebyshevSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & _SmootherMatrix;
   FineOperator   & _SmootherOperator;
@@ -79,6 +80,7 @@ public:
 template<class Field,class Matrix> class MirsSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & SmootherMatrix;
   FineOperator   & SmootherOperator;
@@ -108,6 +110,7 @@ public:
 template<class Field,class Matrix> class RedBlackSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & SmootherMatrix;
   RealD tol;
@@ -134,6 +137,7 @@ public:
 template<class Fobj,class CComplex,int nbasis, class Matrix, class Guesser, class CoarseSolver>
 class MultiGridPreconditioner : public LinearFunction< Lattice<Fobj> > {
 public:
+  using LinearFunction<Lattice<Fobj> >::operator();
 
   typedef Aggregation<Fobj,CComplex,nbasis> Aggregates;
   typedef CoarsenedMatrix<Fobj,CComplex,nbasis> CoarseOperator;
@@ -241,7 +245,7 @@ int main (int argc, char ** argv)
   Grid_init(&argc,&argv);
 
   const int Ls=16;
-  const int rLs=8;
+  //  const int rLs=8;
 
   GridCartesian         * UGrid   = SpaceTimeGrid::makeFourDimGrid(GridDefaultLatt(), GridDefaultSimd(Nd,vComplex::Nsimd()),GridDefaultMpi());
   GridRedBlackCartesian * UrbGrid = SpaceTimeGrid::makeFourDimRedBlackGrid(UGrid);
@@ -388,7 +392,7 @@ int main (int argc, char ** argv)
   //  RedBlackSmoother<LatticeFermion,DomainWallFermionR> FineRBSmoother(0.00,0.001,100,Ddwf);
 
   // Wrap the 2nd level solver in a MultiGrid preconditioner acting on the fine space
-  ZeroGuesser<CoarseVector> CoarseZeroGuesser;
+  //  ZeroGuesser<CoarseVector> CoarseZeroGuesser;
   TwoLevelMG TwoLevelPrecon(Aggregates, LDOp,
 			    HermIndefOp,Ddwf,
 			    FineSmoother,
diff --git a/tests/solver/Test_dwf_hdcr_48_rb.cc b/tests/solver/Test_dwf_hdcr_48_rb.cc
index a4d7bbb9..2b76681e 100644
--- a/tests/solver/Test_dwf_hdcr_48_rb.cc
+++ b/tests/solver/Test_dwf_hdcr_48_rb.cc
@@ -57,7 +57,7 @@ private:
   CheckerBoardedSparseMatrixBase<Field> & _Matrix;
   SchurRedBlackBase<Field> & _Solver;
 public:
-
+  using LinearFunction<Field>::operator();
   /////////////////////////////////////////////////////
   // Wrap the usual normal equations trick
   /////////////////////////////////////////////////////
@@ -75,6 +75,7 @@ public:
 template<class Field,class Matrix> class ChebyshevSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & _SmootherMatrix;
   FineOperator   & _SmootherOperator;
@@ -98,6 +99,7 @@ public:
 template<class Field,class Matrix> class MirsSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & SmootherMatrix;
   FineOperator   & SmootherOperator;
@@ -128,6 +130,7 @@ public:
 template<class Fobj,class CComplex,int nbasis, class Matrix, class Guesser, class CoarseSolver>
 class MultiGridPreconditioner : public LinearFunction< Lattice<Fobj> > {
 public:
+  using LinearFunction<Lattice<Fobj> >::operator();
 
   typedef Aggregation<Fobj,CComplex,nbasis> Aggregates;
   typedef CoarsenedMatrix<Fobj,CComplex,nbasis> CoarseOperator;
diff --git a/tests/solver/Test_dwf_hdcr_48_regression.cc b/tests/solver/Test_dwf_hdcr_48_regression.cc
index d07bd3a5..4dbb097b 100644
--- a/tests/solver/Test_dwf_hdcr_48_regression.cc
+++ b/tests/solver/Test_dwf_hdcr_48_regression.cc
@@ -55,6 +55,7 @@ RealD InverseApproximation(RealD x){
 template<class Field,class Matrix> class ChebyshevSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & _SmootherMatrix;
   FineOperator   & _SmootherOperator;
@@ -78,6 +79,7 @@ public:
 template<class Field,class Matrix> class MirsSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & SmootherMatrix;
   FineOperator   & SmootherOperator;
@@ -108,6 +110,7 @@ public:
 template<class Fobj,class CComplex,int nbasis, class Matrix, class Guesser, class CoarseSolver>
 class MultiGridPreconditioner : public LinearFunction< Lattice<Fobj> > {
 public:
+  using LinearFunction<Lattice<Fobj> >::operator();
 
   typedef Aggregation<Fobj,CComplex,nbasis> Aggregates;
   typedef CoarsenedMatrix<Fobj,CComplex,nbasis> CoarseOperator;
diff --git a/tests/solver/Test_dwf_multigrid.cc b/tests/solver/Test_dwf_multigrid.cc
index 351e10fd..e670b358 100644
--- a/tests/solver/Test_dwf_multigrid.cc
+++ b/tests/solver/Test_dwf_multigrid.cc
@@ -57,6 +57,7 @@ private:
   OperatorFunction<Field> & _Solver;
   LinearFunction<Field>   & _Guess;
 public:
+  using LinearFunction<Field>::operator();
 
   /////////////////////////////////////////////////////
   // Wrap the usual normal equations trick
@@ -118,6 +119,7 @@ RealD InverseApproximation(RealD x){
 template<class Field,class Matrix> class ChebyshevSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & _SmootherMatrix;
   FineOperator   & _SmootherOperator;
@@ -174,6 +176,7 @@ public:
 template<class Fobj,class CComplex,int nbasis, class CoarseSolver>
 class HDCRPreconditioner : public LinearFunction< Lattice<Fobj> > {
 public:
+  using LinearFunction<Lattice<Fobj> >::operator();
 
   typedef Aggregation<Fobj,CComplex,nbasis> Aggregates;
   typedef CoarsenedMatrix<Fobj,CComplex,nbasis> CoarseOperator;
diff --git a/tests/solver/Test_hw_multigrid_mixed_48.cc b/tests/solver/Test_hw_multigrid_mixed_48.cc
index 6b3b5f56..0e8d6a17 100644
--- a/tests/solver/Test_hw_multigrid_mixed_48.cc
+++ b/tests/solver/Test_hw_multigrid_mixed_48.cc
@@ -456,8 +456,8 @@ public:
 
     siteVector *CBp=Stencil.CommBuf();			
 
-    int ptype;
-    int nb2=nbasis/2;
+    //    int ptype;
+    //    int nb2=nbasis/2;
     
     autoView(in_v ,   in, AcceleratorRead);
     autoView(st, Stencil, AcceleratorRead);
@@ -471,7 +471,7 @@ public:
 	  typedef decltype(coalescedRead(in_v[0])) calcVector;
 	  typedef decltype(coalescedRead(in_v[0](0))) calcComplex;
 	  int sU = sF/Ls;
-	  int  s = sF%Ls;
+	  //	  int  s = sF%Ls;
 
 	  calcComplex res = Zero();
 	  calcVector  nbr;
@@ -517,14 +517,14 @@ public:
     autoView(st, Stencil, AcceleratorRead);
     siteVector *CBp=Stencil.CommBuf();			
 
-    int ptype;
-    int nb2=nbasis/2;
+    //    int ptype;
+    //    int nb2=nbasis/2;
     accelerator_for2d(sF, Coarse5D->oSites(), b, nbasis, Nsimd, {
 
       typedef decltype(coalescedRead(in_v[0])) calcVector;
       typedef decltype(coalescedRead(in_v[0](0))) calcComplex;
       int sU = sF/Ls;
-      int  s = sF%Ls;
+      //      int  s = sF%Ls;
 
       calcComplex res = Zero();
 
@@ -650,7 +650,7 @@ private:
   OperatorFunction<Field> & _Solver;
   LinearFunction<Field>   & _Guess;
 public:
-
+  using LinearFunction<Field>::operator();
   /////////////////////////////////////////////////////
   // Wrap the usual normal equations trick
   /////////////////////////////////////////////////////
@@ -712,6 +712,7 @@ RealD InverseApproximation(RealD x){
 template<class Field,class Matrix> class ChebyshevSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & _SmootherMatrix;
   FineOperator   & _SmootherOperator;
@@ -735,6 +736,7 @@ public:
 template<class Fobj,class CComplex,int nbasis, class CoarseSolver>
 class MGPreconditioner : public LinearFunction< Lattice<Fobj> > {
 public:
+  using LinearFunction<Lattice<Fobj> >::operator();
 
   typedef Aggregation<Fobj,CComplex,nbasis> Aggregates;
   typedef typename Aggregation<Fobj,CComplex,nbasis>::CoarseVector CoarseVector;
@@ -831,6 +833,7 @@ public:
 template<class Fobj,class CComplex,int nbasis, class CoarseSolver>
 class HDCRPreconditioner : public LinearFunction< Lattice<Fobj> > {
 public:
+  using LinearFunction<Lattice<Fobj> >::operator();
 
   typedef Aggregation<Fobj,CComplex,nbasis> Aggregates;
   typedef typename Aggregation<Fobj,CComplex,nbasis>::CoarseVector CoarseVector;
@@ -1174,18 +1177,18 @@ int main (int argc, char ** argv)
   PlainHermOp<CoarseCoarseVector> IRLOpL2    (IRLHermOpL2);
   ImplicitlyRestartedLanczos<CoarseCoarseVector> IRLL2(IRLOpChebyL2,IRLOpL2,cNstop,cNk,cNm,1.0e-3,20);
 
-  int cNconv;
   cNm=0;
   std::vector<RealD>          eval2(cNm);
   std::vector<CoarseCoarseVector>   evec2(cNm,CoarseCoarse5d);
   cc_src=1.0;
+  //  int cNconv;
   //  IRLL2.calc(eval2,evec2,cc_src,cNconv);
 
   ConjugateGradient<CoarseCoarseVector>  CoarseCoarseCG(0.02,10000);
   DeflatedGuesser<CoarseCoarseVector> DeflCoarseCoarseGuesser(evec2,eval2);
   NormalEquations<CoarseCoarseVector> DeflCoarseCoarseCGNE(cc_Dwf,CoarseCoarseCG,DeflCoarseCoarseGuesser);
 
-  ZeroGuesser<CoarseVector> CoarseZeroGuesser;
+  //  ZeroGuesser<CoarseVector> CoarseZeroGuesser;
   ZeroGuesser<CoarseCoarseVector>       CoarseCoarseZeroGuesser;
 
   std::cout<<GridLogMessage << "**************************************************"<< std::endl;
diff --git a/tests/solver/Test_hw_multigrid_mixed_48_rb.cc b/tests/solver/Test_hw_multigrid_mixed_48_rb.cc
index 41257e94..e7ceb022 100644
--- a/tests/solver/Test_hw_multigrid_mixed_48_rb.cc
+++ b/tests/solver/Test_hw_multigrid_mixed_48_rb.cc
@@ -456,8 +456,8 @@ public:
 
     siteVector *CBp=Stencil.CommBuf();			
 
-    int ptype;
-    int nb2=nbasis/2;
+    //int ptype;
+    //    int nb2=nbasis/2;
     
     autoView(in_v ,   in, AcceleratorRead);
     autoView(st, Stencil, AcceleratorRead);
@@ -471,7 +471,7 @@ public:
 	  typedef decltype(coalescedRead(in_v[0])) calcVector;
 	  typedef decltype(coalescedRead(in_v[0](0))) calcComplex;
 	  int sU = sF/Ls;
-	  int  s = sF%Ls;
+	  //	  int  s = sF%Ls;
 
 	  calcComplex res = Zero();
 	  calcVector  nbr;
@@ -517,14 +517,14 @@ public:
     autoView(st, Stencil, AcceleratorRead);
     siteVector *CBp=Stencil.CommBuf();			
 
-    int ptype;
-    int nb2=nbasis/2;
+    //    int ptype;
+    //    int nb2=nbasis/2;
     accelerator_for2d(sF, Coarse5D->oSites(), b, nbasis, Nsimd, {
 
       typedef decltype(coalescedRead(in_v[0])) calcVector;
       typedef decltype(coalescedRead(in_v[0](0))) calcComplex;
       int sU = sF/Ls;
-      int  s = sF%Ls;
+      //      int  s = sF%Ls;
 
       calcComplex res = Zero();
 
@@ -648,7 +648,7 @@ private:
   CheckerBoardedSparseMatrixBase<Field> & _Matrix;
   SchurRedBlackBase<Field> & _Solver;
 public:
-
+  using LinearFunction<Field>::operator();
   /////////////////////////////////////////////////////
   // Wrap the usual normal equations trick
   /////////////////////////////////////////////////////
@@ -669,6 +669,7 @@ private:
   OperatorFunction<Field> & _Solver;
   LinearFunction<Field>   & _Guess;
 public:
+  using LinearFunction<Field>::operator();
 
   /////////////////////////////////////////////////////
   // Wrap the usual normal equations trick
@@ -731,6 +732,7 @@ RealD InverseApproximation(RealD x){
 template<class Field,class Matrix> class ChebyshevSmoother : public LinearFunction<Field>
 {
 public:
+  using LinearFunction<Field>::operator();
   typedef LinearOperatorBase<Field>                            FineOperator;
   Matrix         & _SmootherMatrix;
   FineOperator   & _SmootherOperator;
@@ -754,6 +756,7 @@ public:
 template<class Fobj,class CComplex,int nbasis, class CoarseSolver>
 class MGPreconditioner : public LinearFunction< Lattice<Fobj> > {
 public:
+  using LinearFunction<Lattice<Fobj> >::operator();
 
   typedef Aggregation<Fobj,CComplex,nbasis> Aggregates;
   typedef typename Aggregation<Fobj,CComplex,nbasis>::CoarseVector CoarseVector;
@@ -850,7 +853,8 @@ public:
 template<class Fobj,class CComplex,int nbasis, class CoarseSolver>
 class HDCRPreconditioner : public LinearFunction< Lattice<Fobj> > {
 public:
-
+  using LinearFunction<Lattice<Fobj> >::operator();
+  
   typedef Aggregation<Fobj,CComplex,nbasis> Aggregates;
   typedef typename Aggregation<Fobj,CComplex,nbasis>::CoarseVector CoarseVector;
   typedef typename Aggregation<Fobj,CComplex,nbasis>::CoarseMatrix CoarseMatrix;
@@ -1194,11 +1198,11 @@ int main (int argc, char ** argv)
   PlainHermOp<CoarseCoarseVector> IRLOpL2    (IRLHermOpL2);
   ImplicitlyRestartedLanczos<CoarseCoarseVector> IRLL2(IRLOpChebyL2,IRLOpL2,cNstop,cNk,cNm,1.0e-3,20);
 
-  int cNconv;
   cNm=0;
   std::vector<RealD>          eval2(cNm);
   std::vector<CoarseCoarseVector>   evec2(cNm,CoarseCoarse5d);
   cc_src=1.0;
+  //  int cNconv;
   //  IRLL2.calc(eval2,evec2,cc_src,cNconv);
   
   std::vector<RealD> tols ({0.005,0.001});
@@ -1218,10 +1222,10 @@ int main (int argc, char ** argv)
   for(auto c_hi : c_his ) {
   for(auto f_lo : f_los ) {
   for(auto f_hi : f_his ) {
-  ZeroGuesser<CoarseVector> CoarseZeroGuesser;
-  ZeroGuesser<CoarseCoarseVector>       CoarseCoarseZeroGuesser;
+    //  ZeroGuesser<CoarseVector> CoarseZeroGuesser;
+    //  ZeroGuesser<CoarseCoarseVector>       CoarseCoarseZeroGuesser;
   ConjugateGradient<CoarseCoarseVector>  CoarseCoarseCG(tol,10000);
-  ZeroGuesser<CoarseCoarseVector> CoarseCoarseGuesser;
+  //  ZeroGuesser<CoarseCoarseVector> CoarseCoarseGuesser;
   SchurRedBlackDiagMooeeSolve<CoarseCoarseVector> CoarseCoarseRBCG(CoarseCoarseCG);
   SchurSolverWrapper<CoarseCoarseVector> CoarseCoarseSolver(cc_Dwf,CoarseCoarseRBCG);
 
diff --git a/tests/solver/Test_multigrid_common.h b/tests/solver/Test_multigrid_common.h
index 22743b72..0cb63530 100644
--- a/tests/solver/Test_multigrid_common.h
+++ b/tests/solver/Test_multigrid_common.h
@@ -143,6 +143,7 @@ public:
 
 template<class Field> class MultiGridPreconditionerBase : public LinearFunction<Field> {
 public:
+  using LinearFunction<Field>::operator();
   virtual ~MultiGridPreconditionerBase()               = default;
   virtual void setup()                                 = 0;
   virtual void operator()(Field const &in, Field &out) = 0;
@@ -156,6 +157,7 @@ public:
   /////////////////////////////////////////////
   // Type Definitions
   /////////////////////////////////////////////
+  using MultiGridPreconditionerBase<Lattice<Fobj>>::operator();
 
   // clang-format off
   typedef Aggregation<Fobj, CComplex, nBasis>                                                                         Aggregates;
@@ -568,6 +570,7 @@ public:
   /////////////////////////////////////////////
   // Type Definitions
   /////////////////////////////////////////////
+  using MultiGridPreconditionerBase<Lattice<Fobj>>::operator();
 
   typedef Matrix        FineDiracMatrix;
   typedef Lattice<Fobj> FineVector;
diff --git a/tests/solver/Test_wilson_qmr_unprec.cc b/tests/solver/Test_wilson_qmr_unprec.cc
index 45e241e6..c0b42a28 100644
--- a/tests/solver/Test_wilson_qmr_unprec.cc
+++ b/tests/solver/Test_wilson_qmr_unprec.cc
@@ -56,7 +56,6 @@ int main (int argc, char ** argv)
   QuasiMinimalResidual<LatticeFermion> QMR(1.0e-8,10000);
   
   RealD mass=0.0;
-  RealD M5=1.8;
   WilsonFermionR Dw(Umu,*Grid,*rbGrid,mass);
 
   NonHermitianLinearOperator<WilsonFermionR,LatticeFermion> NonHermOp(Dw);