From a6a64df0766400b86fdb6e02ee2e06ba8d8afa79 Mon Sep 17 00:00:00 2001
From: Martin Kronbichler <martin.kronbichler@uni-a.de>
Date: Fri, 30 Jun 2023 12:28:25 +0200
Subject: [PATCH] MatrixFree: Reduce header inclusions in expensive factory
 files

---
 include/deal.II/matrix_free/dof_info.h    | 6 +++++-
 include/deal.II/matrix_free/matrix_free.h | 1 +
 source/matrix_free/dof_info.cc            | 1 +
 3 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/include/deal.II/matrix_free/dof_info.h b/include/deal.II/matrix_free/dof_info.h
index 914b2afcd4..fc20190324 100644
--- a/include/deal.II/matrix_free/dof_info.h
+++ b/include/deal.II/matrix_free/dof_info.h
@@ -25,7 +25,6 @@
 
 #include <deal.II/matrix_free/face_info.h>
 #include <deal.II/matrix_free/shape_info.h>
-#include <deal.II/matrix_free/vector_data_exchange.h>
 
 #include <array>
 #include <memory>
@@ -48,6 +47,11 @@ namespace internal
 
     template <typename Number>
     struct ConstraintValues;
+
+    namespace VectorDataExchange
+    {
+      class Base;
+    }
   } // namespace MatrixFreeFunctions
 } // namespace internal
 
diff --git a/include/deal.II/matrix_free/matrix_free.h b/include/deal.II/matrix_free/matrix_free.h
index b7c305adec..43a836fc41 100644
--- a/include/deal.II/matrix_free/matrix_free.h
+++ b/include/deal.II/matrix_free/matrix_free.h
@@ -44,6 +44,7 @@
 #include <deal.II/matrix_free/shape_info.h>
 #include <deal.II/matrix_free/task_info.h>
 #include <deal.II/matrix_free/type_traits.h>
+#include <deal.II/matrix_free/vector_data_exchange.h>
 
 #include <cstdlib>
 #include <limits>
diff --git a/source/matrix_free/dof_info.cc b/source/matrix_free/dof_info.cc
index fd86229c5e..530c670f18 100644
--- a/source/matrix_free/dof_info.cc
+++ b/source/matrix_free/dof_info.cc
@@ -22,6 +22,7 @@
 #include <deal.II/lac/sparsity_pattern.h>
 
 #include <deal.II/matrix_free/dof_info.templates.h>
+#include <deal.II/matrix_free/vector_data_exchange.h>
 
 #include <iostream>
 
-- 
2.39.5