added a protection

diff --git a/STEER/AliQADataMaker.cxx b/STEER/AliQADataMaker.cxx
index 80295991569a3648bb1004df77659228b3ac8135..38c880ef8af0f5079dea3875158b4d1c20d86a22 100644 (file)
--- a/STEER/AliQADataMaker.cxx
+++ b/STEER/AliQADataMaker.cxx
@@ -110,13 +110,18 @@ void AliQADataMaker::Finish() const
 TObject * AliQADataMaker::GetData(TObjArray * list, const Int_t index)  
 { 
        // Returns the QA object at index. Limit is 100. 
-       if ( index > 10000 ) {
-               AliError("Max number of authorized QA objects is 10000") ; 
-               return NULL; 
+       if (list) {
+               if ( index > 10000 ) {
+                       AliError("Max number of authorized QA objects is 10000") ; 
+                       return NULL ; 
+               } else {
+                       return list->At(index) ; 
+               }       
        } else {
-               return list->At(index) ; 
+               AliError("Data list is NULL !!") ; 
+               return NULL ;           
        }
-} 
+}
 
 //____________________________________________________________________________
 void AliQADataMaker::Reset(const Bool_t sameCycle)