Cypclass generation in ModuleNode (with virtual inheritance)

Cython/Compiler/ModuleNode.py

@@ -6,7 +6,7 @@ from __future__ import absolute_import
 
 import cython
 cython.declare(Naming=object, Options=object, PyrexTypes=object, TypeSlots=object,
-               error=object, warning=object, py_object_type=object, UtilityCode=object,
+               error=object, warning=object, py_object_type=object, cy_object_type=object, UtilityCode=object,
                EncodedString=object, re=object)
 
 from collections import defaultdict
@@ -27,7 +27,7 @@ from . import PyrexTypes
 from . import Pythran
 
 from .Errors import error, warning
-from .PyrexTypes import py_object_type
+from .PyrexTypes import py_object_type, cy_object_type
 from ..Utils import open_new_file, replace_suffix, decode_filename, build_hex_version
 from .Code import UtilityCode, IncludeCode
 from .StringEncoding import EncodedString
@@ -907,8 +907,10 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
             # Just let everything be public.
             code.put("struct %s" % type.cname)
             if type.base_classes:
-                base_class_decl = ", public ".join(
-                    [base_class.empty_declaration_code() for base_class in type.base_classes])
+                base_class_list = [base_class.empty_declaration_code() for base_class in type.base_classes]
+                if type.is_cyp_class and type.base_classes[-1] is cy_object_type:
+                    base_class_list[-1] = "virtual " + base_class_list[-1]
+                base_class_decl = ", public ".join(base_class_list)
                 code.put(" : public %s" % base_class_decl)
             code.putln(" {")
             self.generate_type_header_code(scope.type_entries, code)
@@ -1011,6 +1013,10 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
                   code.putln("%s& operator=(const %s& __Pyx_other);" % (type.cname, type.cname))
             code.putln("};")
 
+        if type.is_cyp_class:
+            code.globalstate.use_utility_code(
+                UtilityCode.load_cached("CythonReferenceCounting", "ObjectHandling.c"))
+
     def generate_enum_definition(self, entry, code):
         code.mark_pos(entry.pos)
         type = entry.type