fix crash during C++ class type inference

Cython/Compiler/ExprNodes.py

@@ -4163,9 +4163,10 @@ class CallNode(ExprNode):
 
     def infer_type(self, env):
         function = self.function
+        func_type = function.infer_type(env)
         if isinstance(function, NewExprNode):
+            # note: needs call to infer_type() above
             return PyrexTypes.CPtrType(function.class_type)
-        func_type = function.infer_type(env)
         if func_type is py_object_type:
             # function might have lied for safety => try to find better type
             entry = getattr(function, 'entry', None)