CarpetLib: Correct errors in handling mem<T> objects

I think there were some errors in handling the mem<T> objects, but I'm
not completely sure.

darcs-hash:20050411183030-891bb-f1b5510bb4866c8d4bab48a7b320cb6de71b1121.gz

1 files changed, 4 insertions, 0 deletions

diff --git a/Carpet/CarpetLib/src/data.hh b/Carpet/CarpetLib/src/data.hh
index 8d6069de2..f7830c3c1 100644
--- a/Carpet/CarpetLib/src/data.hh
+++ b/Carpet/CarpetLib/src/data.hh
@@ -75,23 +75,27 @@ public:
   virtual const void* storage () const
   {
     assert (_has_storage);
+    if (! _memory) return 0;
     return _memory->storage(vectorindex);
   }
 
   virtual void* storage () {
     assert (_has_storage);
+    if (! _memory) return 0;
     return _memory->storage(vectorindex);
   }
   
   // Data accessors
   const T& operator[] (const ivect& index) const
   {
+    assert (_has_storage);
     assert (_memory);
     return _memory->storage(vectorindex)[offset(index)];
   }
   
   T& operator[] (const ivect& index)
   {
+    assert (_has_storage);
     assert (_memory);
     return _memory->storage(vectorindex)[offset(index)];
   }