From 5f49afd9b84bada93cfe022cc13dccfe8433bbc9 Mon Sep 17 00:00:00 2001
From: Denis Davydov <davydden@gmail.com>
Date: Tue, 30 Oct 2018 16:48:39 +0100
Subject: [PATCH] improve IncrementalFunction

---
 include/deal.II/base/incremental_function.h | 5 -----
 source/base/incremental_function.cc         | 8 +++++---
 2 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/include/deal.II/base/incremental_function.h b/include/deal.II/base/incremental_function.h
index 0bce2c773c..7ca4d13399 100644
--- a/include/deal.II/base/incremental_function.h
+++ b/include/deal.II/base/incremental_function.h
@@ -68,11 +68,6 @@ namespace Functions
      */
     IncrementalFunction(Function<dim, RangeNumberType> &base);
 
-    /**
-     * Virtual destructor
-     */
-    virtual ~IncrementalFunction() = default;
-
     /**
      * Return the value of the function at the given point.
      *
diff --git a/source/base/incremental_function.cc b/source/base/incremental_function.cc
index f5e23b1c40..49bde1148c 100644
--- a/source/base/incremental_function.cc
+++ b/source/base/incremental_function.cc
@@ -14,6 +14,7 @@
 // ---------------------------------------------------------------------
 
 #include <deal.II/base/incremental_function.h>
+#include <deal.II/base/signaling_nan.h>
 
 #include <deal.II/lac/vector.h>
 
@@ -25,7 +26,7 @@ namespace Functions
   IncrementalFunction<dim, RangeNumberType>::IncrementalFunction(
     Function<dim, RangeNumberType> &base)
     : base(base)
-    , delta_t(time_type())
+    , delta_t(numbers::signaling_nan<time_type>())
     , values_old(base.n_components)
   {}
 
@@ -45,8 +46,9 @@ namespace Functions
 
   template <int dim, typename RangeNumberType>
   RangeNumberType
-  IncrementalFunction<dim, RangeNumberType>::value(const Point<dim> &p,
-                                                   unsigned int      comp) const
+  IncrementalFunction<dim, RangeNumberType>::value(
+    const Point<dim> & p,
+    const unsigned int comp) const
   {
     // Cache the time state of the base class in case it has been changed
     // within the user code. We reset the wrapped function to the original
-- 
2.39.5