From 258ed7f4670b3f1b020712b853e89213ede462ce Mon Sep 17 00:00:00 2001
From: Guido Kanschat <dr.guido.kanschat@gmail.com>
Date: Wed, 24 May 2000 22:32:42 +0000
Subject: [PATCH] dependence on forward_declarations.h removed for speed

git-svn-id: https://svn.dealii.org/trunk@2941 0785d39b-7218-0410-832d-ea1e28bc413d
---
 deal.II/deal.II/include/dofs/dof_accessor.h   |  6 +-
 .../deal.II/include/dofs/dof_constraints.h    |  6 +-
 deal.II/deal.II/include/dofs/dof_handler.h    | 13 +++-
 deal.II/deal.II/include/dofs/dof_tools.h      |  4 +-
 deal.II/deal.II/include/fe/fe_values.h        |  2 +
 deal.II/deal.II/include/grid/grid_generator.h |  5 +-
 deal.II/deal.II/include/grid/grid_in.h        |  2 +-
 deal.II/deal.II/include/grid/grid_out.h       |  2 +-
 deal.II/deal.II/include/grid/intergrid_map.h  |  1 +
 deal.II/deal.II/include/grid/tria.h           | 14 +++-
 deal.II/deal.II/include/grid/tria_accessor.h  | 13 +++-
 deal.II/deal.II/include/grid/tria_boundary.h  |  2 +-
 deal.II/deal.II/include/grid/tria_iterator.h  |  2 +-
 deal.II/deal.II/include/multigrid/mg_base.h   |  5 +-
 .../include/multigrid/mg_dof_accessor.h       |  1 +
 .../include/multigrid/mg_dof_handler.h        |  2 +
 .../deal.II/include/multigrid/mg_dof_tools.h  |  3 -
 .../deal.II/include/multigrid/mg_smoother.h   |  2 +-
 deal.II/deal.II/include/numerics/base.h       |  2 +
 deal.II/deal.II/include/numerics/data_io.h    |  5 +-
 deal.II/deal.II/include/numerics/data_out.h   |  3 +-
 .../deal.II/include/numerics/data_out_stack.h |  3 +-
 .../include/numerics/dof_renumbering.h        |  1 -
 .../include/numerics/error_estimator.h        |  1 -
 deal.II/deal.II/include/numerics/matrices.h   | 10 +++
 deal.II/deal.II/include/numerics/vectors.h    | 12 +++-
 deal.II/deal.II/source/multigrid/mg_base.cc   | 13 +++-
 deal.II/lac/include/lac/block_sparse_matrix.h |  2 +-
 .../lac/include/lac/block_sparsity_pattern.h  |  1 -
 deal.II/lac/include/lac/eigen.h               |  1 -
 deal.II/lac/include/lac/precondition_block.h  | 32 ++++++++-
 .../lac/precondition_block.templates.h        | 65 +++++++++++++++++++
 deal.II/lac/include/lac/solver.h              |  5 +-
 deal.II/lac/include/lac/solver_selector.h     |  1 -
 deal.II/lac/include/lac/sparse_matrix.h       |  1 +
 deal.II/lac/include/lac/sparse_vanka.h        |  4 +-
 deal.II/lac/include/lac/sparsity_pattern.h    |  3 +-
 deal.II/lac/source/precondition_block.cc      | 26 ++++++++
 tests/deal.II/mglocal.cc                      | 10 +--
 39 files changed, 234 insertions(+), 52 deletions(-)

diff --git a/deal.II/deal.II/include/dofs/dof_accessor.h b/deal.II/deal.II/include/dofs/dof_accessor.h
index ffbd26e55d..95cdffd9c1 100644
--- a/deal.II/deal.II/include/dofs/dof_accessor.h
+++ b/deal.II/deal.II/include/dofs/dof_accessor.h
@@ -18,9 +18,13 @@
 
 
 #include <grid/tria_accessor.h>
-#include <lac/forward_declarations.h>
 #include <vector>
 
+template <typename number> class FullMatrix;
+template <typename number> class SparseMatrix;
+template <typename number> class Vector;
+
+template <int dim> class DoFHandler;
 
 // note: in non-debug mode, i.e. with optimizations, the file
 // dof_accessor.templates.h is included at the end of this file.
diff --git a/deal.II/deal.II/include/dofs/dof_constraints.h b/deal.II/deal.II/include/dofs/dof_constraints.h
index 0dd6b3c9b4..71ec847299 100644
--- a/deal.II/deal.II/include/dofs/dof_constraints.h
+++ b/deal.II/deal.II/include/dofs/dof_constraints.h
@@ -18,8 +18,12 @@
 #include <utility>
 #include <base/exceptions.h>
 #include <base/subscriptor.h>
-#include <lac/forward_declarations.h>
 
+class SparsityPattern;
+template <int rows, int columns> class BlockSparsityPattern;
+template <typename number> class SparseMatrix;
+template <typename number, int rows, int columns> class BlockSparseMatrix;
+template <int n_blocks> class BlockIndices;
 
 /**
  * This class represents the matrix denoting the distribution of the degrees
diff --git a/deal.II/deal.II/include/dofs/dof_handler.h b/deal.II/deal.II/include/dofs/dof_handler.h
index 1631309634..5aa4eddf70 100644
--- a/deal.II/deal.II/include/dofs/dof_handler.h
+++ b/deal.II/deal.II/include/dofs/dof_handler.h
@@ -19,11 +19,18 @@
 #include <vector>
 #include <map>
 #include <base/exceptions.h>
-#include <base/forward_declarations.h>
 #include <base/smartpointer.h>
-#include <grid/forward_declarations.h>
-#include <lac/forward_declarations.h>
 
+template <int dim> class Function;
+
+template <int dim> class DoFCellAccessor;
+template <int dim> class DoFLevel;
+template<int celldim, int dim> class DoFObjectAccessor;
+template <int dim> class FiniteElement;
+template <int dim, typename Accessor> class TriaRawIterator;
+template <int dim, typename Accessor> class TriaIterator;
+template <int dim, typename Accessor> class TriaActiveIterator;
+template <int dim> class Triangulation;
 
 /**
  * Define some types which differ between the dimensions. This class
diff --git a/deal.II/deal.II/include/dofs/dof_tools.h b/deal.II/deal.II/include/dofs/dof_tools.h
index af6dc71a7a..2332048219 100644
--- a/deal.II/deal.II/include/dofs/dof_tools.h
+++ b/deal.II/deal.II/include/dofs/dof_tools.h
@@ -18,10 +18,10 @@
 
 
 #include <base/exceptions.h>
-#include <lac/forward_declarations.h>
-#include <grid/forward_declarations.h>
 #include <vector>
 
+template <int dim> class MGDoFHandler;
+template <template <int> class GridClass, int dim> class InterGridMap;
 
 /**
  * This is a collection of functions operating on, and manipulating
diff --git a/deal.II/deal.II/include/fe/fe_values.h b/deal.II/deal.II/include/fe/fe_values.h
index 164d08023e..633f795720 100644
--- a/deal.II/deal.II/include/fe/fe_values.h
+++ b/deal.II/deal.II/include/fe/fe_values.h
@@ -23,6 +23,8 @@
 #include <grid/tria.h>
 #include <fe/fe_update_flags.h>
 
+template <int dim> class Quadrature;
+
 
 /**
  *  This class offers a multitude of arrays and other fields which are used by
diff --git a/deal.II/deal.II/include/grid/grid_generator.h b/deal.II/deal.II/include/grid/grid_generator.h
index 471af52af3..f447a670cf 100644
--- a/deal.II/deal.II/include/grid/grid_generator.h
+++ b/deal.II/deal.II/include/grid/grid_generator.h
@@ -14,10 +14,11 @@
 #define __deal2__grid_generator_h
 
 
-#include <base/forward_declarations.h>
-#include <grid/forward_declarations.h>
 #include <base/exceptions.h>
 
+template <int dim> class Point;
+template <int dim> class Triangulation;
+
 
 /**
  * This class offers triangulations of some standard domains such as hypercubes,
diff --git a/deal.II/deal.II/include/grid/grid_in.h b/deal.II/deal.II/include/grid/grid_in.h
index fee29e5cd0..e7c87afa09 100644
--- a/deal.II/deal.II/include/grid/grid_in.h
+++ b/deal.II/deal.II/include/grid/grid_in.h
@@ -16,11 +16,11 @@
 
 #include <base/exceptions.h>
 #include <base/smartpointer.h>
-#include <grid/forward_declarations.h>
 #include <iostream>
 #include <vector>
 #include <string>
 
+template <int dim> class Triangulation;
 
 /**
  * This class implements an input mechanism for grid data. It allows to
diff --git a/deal.II/deal.II/include/grid/grid_out.h b/deal.II/deal.II/include/grid/grid_out.h
index e16c1439b0..1fa6704210 100644
--- a/deal.II/deal.II/include/grid/grid_out.h
+++ b/deal.II/deal.II/include/grid/grid_out.h
@@ -14,10 +14,10 @@
 #define __deal2__grid_out_h
 
 
-#include <grid/forward_declarations.h>
 #include <base/exceptions.h>
 #include <string>
 
+template <int dim> class Triangulation;
 
 /**
  * This class provides a means to output a triangulation to a file in different
diff --git a/deal.II/deal.II/include/grid/intergrid_map.h b/deal.II/deal.II/include/grid/intergrid_map.h
index cdd90bd5a3..65f5078082 100644
--- a/deal.II/deal.II/include/grid/intergrid_map.h
+++ b/deal.II/deal.II/include/grid/intergrid_map.h
@@ -13,6 +13,7 @@
 #ifndef __deal2__intergrid_map_h
 #define __deal2__intergrid_map_h
 
+template <class T> class SmartPointer;
 
 /**
  * This class provides a map between two grids which are derived from
diff --git a/deal.II/deal.II/include/grid/tria.h b/deal.II/deal.II/include/grid/tria.h
index 4440d63a95..25f37423b1 100644
--- a/deal.II/deal.II/include/grid/tria.h
+++ b/deal.II/deal.II/include/grid/tria.h
@@ -15,13 +15,21 @@
 
 
 #include <vector>
-#include <grid/forward_declarations.h>
-#include <lac/forward_declarations.h>
-#include <base/forward_declarations.h>
 #include <base/point.h>
 #include <grid/geometry_info.h>
 #include <base/subscriptor.h>
 
+template <int dim> class Boundary;
+template <int dim> class StraightBoundary;
+template <int dim> class CellAccessor;
+template<int celldim, int dim> class TriaObjectAccessor;
+template <int dim, typename Accessor> class TriaRawIterator;
+template <int dim, typename Accessor> class TriaIterator;
+template <int dim, typename Accessor> class TriaActiveIterator;
+template <int dim> class TriangulationLevel;
+template <int dim> class DoFHandler;
+template <int dim> class MGDoFHandler;
+
 /*------------------------------------------------------------------------*/
 
 
diff --git a/deal.II/deal.II/include/grid/tria_accessor.h b/deal.II/deal.II/include/grid/tria_accessor.h
index 7c3d454eba..7f1cefe083 100644
--- a/deal.II/deal.II/include/grid/tria_accessor.h
+++ b/deal.II/deal.II/include/grid/tria_accessor.h
@@ -15,10 +15,18 @@
 
 
 #include <base/exceptions.h>
-#include <base/forward_declarations.h>
-#include <grid/forward_declarations.h>
 #include <grid/tria_iterator_base.h>
 
+template <int dim> class Point;
+
+template <int dim> class Triangulation;
+template <int dim, typename Accessor> class TriaRawIterator;
+template <int dim, typename Accessor> class TriaIterator;
+template <int dim, typename Accessor> class TriaActiveIterator;
+class Line;
+class Quad;
+class Hexahedron;
+
 
 // note: in non-debug mode, i.e. with optimizations, the file
 // tria_accessor.templates.h is included at the end of this file.
@@ -65,7 +73,6 @@ class TriaAccessor
 		    present_index (index),
 		    tria (parent) {};
 
-
 				     /**
 				      *  Copy operator. Since this is only
 				      *  called from iterators, do not
diff --git a/deal.II/deal.II/include/grid/tria_boundary.h b/deal.II/deal.II/include/grid/tria_boundary.h
index 4d0ed02d82..dd6cd26812 100644
--- a/deal.II/deal.II/include/grid/tria_boundary.h
+++ b/deal.II/deal.II/include/grid/tria_boundary.h
@@ -19,8 +19,8 @@
 #include <base/point.h>
 #include <base/subscriptor.h>
 #include <grid/geometry_info.h>
-#include <grid/forward_declarations.h>
 
+template <int dim> class Triangulation;
 
 /**
  *   This class is used to represent a boundary to a triangulation.
diff --git a/deal.II/deal.II/include/grid/tria_iterator.h b/deal.II/deal.II/include/grid/tria_iterator.h
index e194bd4e8d..c28a6feece 100644
--- a/deal.II/deal.II/include/grid/tria_iterator.h
+++ b/deal.II/deal.II/include/grid/tria_iterator.h
@@ -22,8 +22,8 @@
 #include <base/exceptions.h>
 #include <base/point.h>
 #include <grid/tria_iterator_base.h>
-#include <grid/forward_declarations.h>
 
+template <int dim> class Triangulation;
 
 // note: in non-debug mode, i.e. with optimizations, the file
 // tria_iterator.templates.h is included at the end of this file.
diff --git a/deal.II/deal.II/include/multigrid/mg_base.h b/deal.II/deal.II/include/multigrid/mg_base.h
index 4e0396528e..b53705d6b5 100644
--- a/deal.II/deal.II/include/multigrid/mg_base.h
+++ b/deal.II/deal.II/include/multigrid/mg_base.h
@@ -21,11 +21,10 @@
 #include <base/smartpointer.h>
 #include <lac/vector.h>
 
-#include <lac/forward_declarations.h>
-#include <grid/forward_declarations.h>
-
 #include <vector>
 
+class MGSmootherBase;
+
 
 /**
  * An array with an object for each level.  The purpose of this class
diff --git a/deal.II/deal.II/include/multigrid/mg_dof_accessor.h b/deal.II/deal.II/include/multigrid/mg_dof_accessor.h
index bd9eb79008..0ddec96952 100644
--- a/deal.II/deal.II/include/multigrid/mg_dof_accessor.h
+++ b/deal.II/deal.II/include/multigrid/mg_dof_accessor.h
@@ -16,6 +16,7 @@
 
 #include <dofs/dof_accessor.h>
 
+template <int dim> class MGDoFHandler;
 
 /**
  * Define the basis for accessors to the degrees of freedom for
diff --git a/deal.II/deal.II/include/multigrid/mg_dof_handler.h b/deal.II/deal.II/include/multigrid/mg_dof_handler.h
index 287d9322c1..4db78746b6 100644
--- a/deal.II/deal.II/include/multigrid/mg_dof_handler.h
+++ b/deal.II/deal.II/include/multigrid/mg_dof_handler.h
@@ -19,6 +19,8 @@
 
 #include <dofs/dof_handler.h>
 
+template <int dim> class MGDoFCellAccessor;
+template <int celldim, int dim> class MGDoFObjectAccessor;
 
 /**
  * Define some types which differ between the dimensions. This class
diff --git a/deal.II/deal.II/include/multigrid/mg_dof_tools.h b/deal.II/deal.II/include/multigrid/mg_dof_tools.h
index 5c23a77418..d4da86b441 100644
--- a/deal.II/deal.II/include/multigrid/mg_dof_tools.h
+++ b/deal.II/deal.II/include/multigrid/mg_dof_tools.h
@@ -14,9 +14,6 @@
 #define __deal2__mg_dof_tools_h
 
 
-#include <lac/forward_declarations.h>
-#include <grid/forward_declarations.h>
-
 //TODO: Consider incorporating these functions in DoFTools
 
 /**
diff --git a/deal.II/deal.II/include/multigrid/mg_smoother.h b/deal.II/deal.II/include/multigrid/mg_smoother.h
index aff3374722..dd5dc9b3c8 100644
--- a/deal.II/deal.II/include/multigrid/mg_smoother.h
+++ b/deal.II/deal.II/include/multigrid/mg_smoother.h
@@ -16,10 +16,10 @@
 
 #include <lac/forward_declarations.h>
 #include <multigrid/mg_base.h>
-#include <grid/forward_declarations.h>
 #include <base/smartpointer.h>
 #include <vector>
 
+template <int dim> class MGDoFHandler;
 
 /**
  * Abstract base class for multigrid smoothers.
diff --git a/deal.II/deal.II/include/numerics/base.h b/deal.II/deal.II/include/numerics/base.h
index b4ba0b01ab..b91856b5fe 100644
--- a/deal.II/deal.II/include/numerics/base.h
+++ b/deal.II/deal.II/include/numerics/base.h
@@ -24,6 +24,8 @@
 #include <map>
 #include <string>
 
+template <int dim> class DataOut;
+
 
 /**
  * The use of this class is now deprecated!
diff --git a/deal.II/deal.II/include/numerics/data_io.h b/deal.II/deal.II/include/numerics/data_io.h
index 4ddbbc247a..acf4d72503 100644
--- a/deal.II/deal.II/include/numerics/data_io.h
+++ b/deal.II/deal.II/include/numerics/data_io.h
@@ -15,11 +15,12 @@
 
 
 #include <base/exceptions.h>
-#include <grid/forward_declarations.h>
-#include <lac/forward_declarations.h>
 #include <vector>
 #include <string>
 
+template <typename number> class Vector;
+template <int dim> class DoFHandler;
+class EpsOutputData;
 
 /**
  * This class is deprecated. Use the #DataOut# class instead.
diff --git a/deal.II/deal.II/include/numerics/data_out.h b/deal.II/deal.II/include/numerics/data_out.h
index bf647770e8..490584367f 100644
--- a/deal.II/deal.II/include/numerics/data_out.h
+++ b/deal.II/deal.II/include/numerics/data_out.h
@@ -14,12 +14,11 @@
 #define __deal2__data_out_h
 
 
-#include <lac/forward_declarations.h>
-#include <grid/forward_declarations.h>
 #include <base/data_out_base.h>
 #include <base/multithread_info.h>
 
 
+template <int dim> class DoFHandler;
 
 /**
  * This is an abstract class which provides the functionality to generate
diff --git a/deal.II/deal.II/include/numerics/data_out_stack.h b/deal.II/deal.II/include/numerics/data_out_stack.h
index 0289205e75..1bb1ec1b89 100644
--- a/deal.II/deal.II/include/numerics/data_out_stack.h
+++ b/deal.II/deal.II/include/numerics/data_out_stack.h
@@ -15,13 +15,12 @@
 
 
 #include <base/data_out_base.h>
-#include <lac/forward_declarations.h>
-#include <grid/forward_declarations.h>
 #include <base/smartpointer.h>
 
 #include <string>
 #include <vector>
 
+template <int dim> class DoFHandler;
 
 /**
  * This class is used to stack the output from several computations
diff --git a/deal.II/deal.II/include/numerics/dof_renumbering.h b/deal.II/deal.II/include/numerics/dof_renumbering.h
index a92c577239..5c195929a5 100644
--- a/deal.II/deal.II/include/numerics/dof_renumbering.h
+++ b/deal.II/deal.II/include/numerics/dof_renumbering.h
@@ -15,7 +15,6 @@
 
 
 #include <base/exceptions.h>
-#include <grid/forward_declarations.h>
 
 
 /**
diff --git a/deal.II/deal.II/include/numerics/error_estimator.h b/deal.II/deal.II/include/numerics/error_estimator.h
index 0d00c620cf..b3bf3528b4 100644
--- a/deal.II/deal.II/include/numerics/error_estimator.h
+++ b/deal.II/deal.II/include/numerics/error_estimator.h
@@ -17,7 +17,6 @@
 #include <base/exceptions.h>
 #include <base/function.h>
 #include <base/multithread_info.h>
-#include <grid/forward_declarations.h>
 #include <dofs/dof_handler.h>
 #include <map>
 
diff --git a/deal.II/deal.II/include/numerics/matrices.h b/deal.II/deal.II/include/numerics/matrices.h
index 9e5ecfaa72..15bd54c875 100644
--- a/deal.II/deal.II/include/numerics/matrices.h
+++ b/deal.II/deal.II/include/numerics/matrices.h
@@ -17,6 +17,16 @@
 #include <base/exceptions.h>
 #include <map>
 
+template <int dim> class Quadrature;
+
+template<typename number> class Vector;
+template<typename number> class FullMatrix;
+template<typename number> class SparseMatrix;
+
+template <typename number, int rows, int columns  >  class BlockSparseMatrix;
+template <int n_blocks, typename Number> class BlockVector;
+template <int dim> class FEValues;
+template <int dim> class Equation;
 
 /**
  * Provide a class which assembles certain standard matrices for a given
diff --git a/deal.II/deal.II/include/numerics/vectors.h b/deal.II/deal.II/include/numerics/vectors.h
index 3b2e82bffd..b5d64ff3f5 100644
--- a/deal.II/deal.II/include/numerics/vectors.h
+++ b/deal.II/deal.II/include/numerics/vectors.h
@@ -14,13 +14,19 @@
 #define __deal2__vectors_h
 
 
-#include <base/forward_declarations.h>
 #include <base/exceptions.h>
-#include <lac/forward_declarations.h>
-#include <grid/forward_declarations.h>
 #include <map>
 #include <vector>
 
+template <int dim> class Function;
+template <int dim> class Quadrature;
+template <int dim> class QGauss2;
+
+template <typename number> class Vector;
+template <typename number> class FullMatrix;
+template <int dim> class DoFHandler;
+class ConstraintMatrix;
+
 
 /**
  *  Denote which norm/integral is to be computed. The following possibilities
diff --git a/deal.II/deal.II/source/multigrid/mg_base.cc b/deal.II/deal.II/source/multigrid/mg_base.cc
index cc3bd3c254..6dd37906b1 100644
--- a/deal.II/deal.II/source/multigrid/mg_base.cc
+++ b/deal.II/deal.II/source/multigrid/mg_base.cc
@@ -53,18 +53,21 @@ MGBase::level_mgstep(const unsigned int        level,
 		     const MGSmootherBase     &post_smooth,
 		     const MGCoarseGridSolver &coarse_grid_solver)
 {
+#ifdef MG_DEBUG
   char *name = new char[100];
-
   sprintf(name, "MG%d-defect",level);
   print_vector(level, defect[level], name);
-  
+#endif
+
   solution[level] = 0.;
   
   if (level == minlevel)
     {
       coarse_grid_solver(level, solution[level], defect[level]);
+#ifdef MG_DEBUG
       sprintf(name, "MG%d-solution",level);
       print_vector(level, solution[level], name);
+#endif
       return;
     }
 
@@ -72,8 +75,10 @@ MGBase::level_mgstep(const unsigned int        level,
   pre_smooth.smooth(level, solution[level], defect[level]);
 				   // t = d-As
 
+#ifdef MG_DEBUG
   sprintf(name, "MG%d-pre",level);
   print_vector(level, solution[level], name);
+#endif
   
   t.reinit(solution[level].size());
   level_vmult(level, t, solution[level], defect[level]);
@@ -96,8 +101,10 @@ MGBase::level_mgstep(const unsigned int        level,
 
   transfer->prolongate(level, t, solution[level-1]);
 
+#ifdef MG_DEBUG
   sprintf(name, "MG%d-cgc",level);
   print_vector(level, t, name);
+#endif
 
   solution[level] += t;
   
@@ -105,10 +112,12 @@ MGBase::level_mgstep(const unsigned int        level,
 
   post_smooth.smooth(level, solution[level], defect[level]);
 
+#ifdef MG_DEBUG
   sprintf(name, "MG%d-post",level);
   print_vector(level, solution[level], name);
 
   delete[] name;
+#endif
 }
 
 
diff --git a/deal.II/lac/include/lac/block_sparse_matrix.h b/deal.II/lac/include/lac/block_sparse_matrix.h
index 6006592770..58bd47d816 100644
--- a/deal.II/lac/include/lac/block_sparse_matrix.h
+++ b/deal.II/lac/include/lac/block_sparse_matrix.h
@@ -17,7 +17,7 @@
 #include <lac/sparse_matrix.h>
 #include <lac/block_sparsity_pattern.h>
 
-
+template <int n_blocks, typename Number> class BlockVector;
 
 /**
  * Blocked sparse matrix. The behaviour of objects of this type is
diff --git a/deal.II/lac/include/lac/block_sparsity_pattern.h b/deal.II/lac/include/lac/block_sparsity_pattern.h
index 7a46e28a07..621400829e 100644
--- a/deal.II/lac/include/lac/block_sparsity_pattern.h
+++ b/deal.II/lac/include/lac/block_sparsity_pattern.h
@@ -16,7 +16,6 @@
 
 #include <base/exceptions.h>
 #include <base/subscriptor.h>
-#include <lac/forward_declarations.h>
 #include <lac/sparsity_pattern.h>
 #include <lac/block_indices.h>
 
diff --git a/deal.II/lac/include/lac/eigen.h b/deal.II/lac/include/lac/eigen.h
index e9489ccae5..6293e80863 100644
--- a/deal.II/lac/include/lac/eigen.h
+++ b/deal.II/lac/include/lac/eigen.h
@@ -14,7 +14,6 @@
 #define __deal2__eigen_h
 
 
-#include <lac/forward_declarations.h>
 #include <lac/solver.h>
 #include <lac/solver_control.h>
 #include <lac/solver_cg.h>
diff --git a/deal.II/lac/include/lac/precondition_block.h b/deal.II/lac/include/lac/precondition_block.h
index 071d4df14b..bc45f9e907 100644
--- a/deal.II/lac/include/lac/precondition_block.h
+++ b/deal.II/lac/include/lac/precondition_block.h
@@ -14,13 +14,16 @@
 #define __deal2__precondition_block_h
 
 
-#include <lac/forward_declarations.h>
 #include <base/exceptions.h>
 #include <base/subscriptor.h>
 #include <base/smartpointer.h>
 
 #include <vector>
 
+template <typename number> class FullMatrix;
+template <typename number> class SparseMatrix;
+template <typename number> class Vector;
+
 
 /**
  * Base class for #PreconditionBlockJacobi#, #PreconditionBlockSOR#, ...
@@ -213,6 +216,33 @@ class PreconditionBlock: public Subscriptor
 };
 
 
+/**
+ * Block Jacobi preconditioning.
+ */
+template<typename number,
+         typename inverse_type = number>
+class PreconditionBlockJacobi : public PreconditionBlock<number,inverse_type>
+{
+  public:
+				     /**
+				      * Execute block Jacobi preconditioning.
+				      * Make sure that the right
+				      * block size
+				      * of the matrix is set by
+				      * #set_block_size#
+				      * before calling this function.
+				      *
+				      * This function will automatically use the
+				      * inverse matrices if they exist, if not
+				      * then BlockJacobi will need much time
+				      * inverting the diagonal block
+				      * matrices in each preconditioning step.
+				      */
+    template <typename number2>
+    void operator() (Vector<number2>&, const Vector<number2>&) const;
+};
+
+
 /**
  * Block SOR preconditioning.
  *
diff --git a/deal.II/lac/include/lac/precondition_block.templates.h b/deal.II/lac/include/lac/precondition_block.templates.h
index 1a299727cf..62d8d5170a 100644
--- a/deal.II/lac/include/lac/precondition_block.templates.h
+++ b/deal.II/lac/include/lac/precondition_block.templates.h
@@ -124,6 +124,71 @@ void PreconditionBlock<number,inverse_type>::invert_diagblocks()
 }
 
 
+/*--------------------- PreconditionBlockJacobi -----------------------*/
+
+
+template <typename number, typename inverse_type>
+template <typename number2>
+void PreconditionBlockJacobi<number,inverse_type>
+::operator() (Vector<number2>       &dst,
+	      const Vector<number2> &src) const
+{
+  Assert(A!=0, ExcNoMatrixGivenToUse());
+  const SparseMatrix<number> &M=*A;
+  Assert (M.m() == M.n(), ExcMatrixNotSquare());
+  Assert (blocksize!=0, ExcBlockSizeNotSet());
+  Assert (M.m()%blocksize==0, ExcWrongBlockSize(blocksize, M.m()));
+  const unsigned int n_cells=M.m()/blocksize;
+  Assert (inverse.size()==0 || inverse.size()==n_cells,
+	  ExcWrongNumberOfInverses(inverse.size(), n_cells));
+
+  Vector<number2> b_cell(blocksize), x_cell(blocksize);
+
+				       // cell_row, cell_column are the
+				       // numbering of the blocks (cells).
+				       // row_cell, column_cell are the local
+				       // numbering of the unknowns in the
+				       // blocks.
+				       // row, column are the global numbering
+				       // of the unkowns.
+  unsigned int row, row_cell, begin_diag_block=0;
+
+  if (inverse.size()==0)
+    {
+      FullMatrix<number> M_cell(blocksize);
+      for (unsigned int cell=0; cell<n_cells; ++cell)
+	{
+	  for (row=cell*blocksize, row_cell=0; row_cell<blocksize; ++row_cell, ++row)
+	    {
+	      b_cell(row_cell)=src(row);
+	      for (unsigned int column_cell=0, column=cell*blocksize;
+		   column_cell<blocksize; ++column_cell, ++column)
+		M_cell(row_cell,column_cell)=M(row,column);
+	    }
+	  M_cell.householder(b_cell);
+	  M_cell.backward(x_cell,b_cell);
+					   // distribute x_cell to dst
+	  for (row=cell*blocksize, row_cell=0; row_cell<blocksize; ++row_cell, ++row)
+	    dst(row)=x_cell(row_cell);
+	  
+	  begin_diag_block+=blocksize;
+	}
+    }
+  else
+    for (unsigned int cell=0; cell<n_cells; ++cell)
+      {
+	for (row=cell*blocksize, row_cell=0; row_cell<blocksize; ++row_cell, ++row)
+	  {
+	    b_cell(row_cell)=src(row);
+	  }
+	inverse[cell].vmult(x_cell, b_cell);
+					 // distribute x_cell to dst
+	for (row=cell*blocksize, row_cell=0; row_cell<blocksize; ++row_cell, ++row)
+	  dst(row)=x_cell(row_cell);
+	
+	begin_diag_block+=blocksize;
+      }
+}
 /*--------------------- PreconditionBlockSOR -----------------------*/
 
 template<typename number, typename inverse_type>
diff --git a/deal.II/lac/include/lac/solver.h b/deal.II/lac/include/lac/solver.h
index 88156952e9..cd90d8a030 100644
--- a/deal.II/lac/include/lac/solver.h
+++ b/deal.II/lac/include/lac/solver.h
@@ -13,8 +13,9 @@
 #ifndef __deal2__solver_h
 #define __deal2__solver_h
 
-
-#include <lac/forward_declarations.h>
+template<typename number> class Vector;
+template<class VECTOR>  class VectorMemory;
+class SolverControl;
 
 
 /**
diff --git a/deal.II/lac/include/lac/solver_selector.h b/deal.II/lac/include/lac/solver_selector.h
index 1122e2a704..2c1aa5087b 100644
--- a/deal.II/lac/include/lac/solver_selector.h
+++ b/deal.II/lac/include/lac/solver_selector.h
@@ -25,7 +25,6 @@
 #include <lac/vector_memory.h>
 #include <lac/solver_richardson.h>
 #include <lac/precondition.h>
-#include <lac/forward_declarations.h>
 
 
 /**
diff --git a/deal.II/lac/include/lac/sparse_matrix.h b/deal.II/lac/include/lac/sparse_matrix.h
index e31c9da1d2..9e55810b52 100644
--- a/deal.II/lac/include/lac/sparse_matrix.h
+++ b/deal.II/lac/include/lac/sparse_matrix.h
@@ -22,6 +22,7 @@
 #include <base/smartpointer.h>
 #include <lac/sparsity_pattern.h>
 
+template<typename number> class Vector;
 
 /**
  * Sparse matrix.
diff --git a/deal.II/lac/include/lac/sparse_vanka.h b/deal.II/lac/include/lac/sparse_vanka.h
index 74427cc2ad..cb318d9b94 100644
--- a/deal.II/lac/include/lac/sparse_vanka.h
+++ b/deal.II/lac/include/lac/sparse_vanka.h
@@ -19,11 +19,13 @@
 
 #include <base/smartpointer.h>
 #include <base/multithread_info.h>
-#include <lac/forward_declarations.h>
 
 #include <vector>
 #include <map>
 
+template <typename number> class FullMatrix;
+template <typename number> class SparseMatrix;
+template <typename number> class Vector;
 
 /**
  * Point-wise Vanka preconditioning.
diff --git a/deal.II/lac/include/lac/sparsity_pattern.h b/deal.II/lac/include/lac/sparsity_pattern.h
index 08825dacc8..b4e07c66ed 100644
--- a/deal.II/lac/include/lac/sparsity_pattern.h
+++ b/deal.II/lac/include/lac/sparsity_pattern.h
@@ -16,7 +16,8 @@
 
 #include <base/exceptions.h>
 #include <base/subscriptor.h>
-#include <lac/forward_declarations.h>
+
+template <typename number> class SparseMatrix;
 
 #include <vector>
 
diff --git a/deal.II/lac/source/precondition_block.cc b/deal.II/lac/source/precondition_block.cc
index 823b11b638..d94b57ac28 100644
--- a/deal.II/lac/source/precondition_block.cc
+++ b/deal.II/lac/source/precondition_block.cc
@@ -29,6 +29,32 @@ template class PreconditionBlock<double, float>;
 template class PreconditionBlock<double, double>;
 
 
+/*--------------------- PreconditionBlockJacobi -----------------------*/
+
+
+// explicit instantiations for "float" PreconditionBlock
+template class PreconditionBlockJacobi<float, float>;
+
+template void PreconditionBlockJacobi<float, float>::operator() (
+  Vector<float> &, const Vector<float> &) const;
+template void PreconditionBlockJacobi<float, float>::operator() (
+  Vector<double> &, const Vector<double> &) const;
+
+
+template class PreconditionBlockJacobi<double, float>;
+
+template void PreconditionBlockJacobi<double, float>::operator() (
+  Vector<float> &, const Vector<float> &) const;
+template void PreconditionBlockJacobi<double, float>::operator() (
+  Vector<double> &, const Vector<double> &) const;
+
+template class PreconditionBlockJacobi<double, double>;
+
+template void PreconditionBlockJacobi<double, double>::operator() (
+  Vector<float> &, const Vector<float> &) const;
+template void PreconditionBlockJacobi<double, double>::operator() (
+  Vector<double> &, const Vector<double> &) const;
+
 /*--------------------- PreconditionBlockGaussSeidel -----------------------*/
 
 
diff --git a/tests/deal.II/mglocal.cc b/tests/deal.II/mglocal.cc
index e2294b4372..b91aa923b3 100644
--- a/tests/deal.II/mglocal.cc
+++ b/tests/deal.II/mglocal.cc
@@ -72,6 +72,7 @@ int main()
 //  logfile.setf(ios::fixed);
 //  logfile.precision (3);
   deallog.attach(logfile);
+  deallog.log_execution_time(true);
 //  deallog.depth_console(0);
 
   Helmholtz equation;
@@ -82,7 +83,7 @@ int main()
   FEQ2<2> fe2;
   FEQ3<2> fe3;
   FEQ4<2> fe4;
-  for (unsigned int degree=1;degree<=4;degree++)
+  for (unsigned int degree=1;degree<=3;degree++)
     {
       Triangulation<2> tr;
       MGDoFHandler<2> mgdof(tr);
@@ -104,12 +105,12 @@ int main()
       cell->set_refine_flag();
       tr.execute_coarsening_and_refinement();
 
-      tr.refine_global(2);
+      tr.refine_global(1);
       dof.distribute_dofs(*fe);
       const unsigned int size = dof.n_dofs();
       deallog << "DoFs " << size << endl;
       deallog << "Levels: " << tr.n_levels() << endl;
-      for (unsigned int step=14;step < 15; ++step)
+      for (unsigned int step=1;step < 3; ++step)
 	{
 	  deallog << "smoothing-steps" << step << endl;
 	  SparsityPattern structure(size, dof.max_couplings_between_dofs());
@@ -143,7 +144,8 @@ int main()
 	  Vector<double> u;
 	  u.reinit(f);
 	  PrimitiveVectorMemory<> mem;
-	  SolverControl control(20, 1.e-8, true);
+
+	  SolverControl control(20, 1.e-12, true);
 	  SolverCG<> solver(control, mem);
 	  
 	  MGLevelObject<SparsityPattern> mgstruct(0, tr.n_levels()-1);
-- 
2.39.5