From ef7b91831ea413407c2457d326b96688431caafa Mon Sep 17 00:00:00 2001
From: wolf <wolf@0785d39b-7218-0410-832d-ea1e28bc413d>
Date: Wed, 2 Feb 2000 14:37:08 +0000
Subject: [PATCH] One optimization, one bugfix for possible problems.

git-svn-id: https://svn.dealii.org/trunk@2328 0785d39b-7218-0410-832d-ea1e28bc413d
---
 deal.II/base/include/base/smartpointer.h | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/deal.II/base/include/base/smartpointer.h b/deal.II/base/include/base/smartpointer.h
index c60294ec5d..e684b6354c 100644
--- a/deal.II/base/include/base/smartpointer.h
+++ b/deal.II/base/include/base/smartpointer.h
@@ -152,7 +152,13 @@ SmartPointer<T>::~SmartPointer () {
 
 
 template <typename T>
-SmartPointer<T> & SmartPointer<T>::operator = (T *tt) {
+SmartPointer<T> & SmartPointer<T>::operator = (T *tt)
+{
+				   // optimize if no real action is
+				   // requested
+  if (t == tt)
+    return *this;
+  
   if (t)
     t->unsubscribe();
   t = tt;
@@ -163,7 +169,14 @@ SmartPointer<T> & SmartPointer<T>::operator = (T *tt) {
 
 
 template <typename T>
-SmartPointer<T> & SmartPointer<T>::operator = (const SmartPointer<T>& tt) {
+SmartPointer<T> & SmartPointer<T>::operator = (const SmartPointer<T>& tt)
+{
+				   // if objects on the left and right
+				   // hand side of the operator= are
+				   // the same, then this is a no-op
+  if (&tt == this)
+    return *this;
+  
   if (t)
     t->unsubscribe();
   t = static_cast<T*>(tt);
-- 
2.39.5