rm tmp variable that isn't needed anymore

theano/compile/profiling.py

@@ -675,6 +675,7 @@ class ProfileStats(object):
                 fct_memory[node.fgraph][node].append(v)
                 fct_shapes[node.fgraph][node].append(sh)
             node_mem[node] = sum_dense
+        del v
 
         # Find the function that used the most of that statistic
         max_sum_size = 0