Adapt dealloc function for cypclass-wrapping c classes

Cython/Compiler/ModuleNode.py

@@ -1554,6 +1554,14 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
         code.putln(
             "static void %s(PyObject *o) {" % slot_func_cname)
 
+        # for cyp wrappers, just decrement the atomic counter of the underlying type
+        is_cyp_wrapper = scope.parent_type.is_cyp_wrapper
+        if is_cyp_wrapper:
+            self.generate_self_cast(scope, code)
+            code.putln("Cy_DECREF(p->%s);" % CypclassWrapper.underlying_name)
+            code.putln("}")
+            return
+
         is_final_type = scope.parent_type.is_final_type
         needs_gc = scope.needs_gc()
         needs_trashcan = scope.needs_trashcan()

Cython/Compiler/Nodes.py

@@ -5355,6 +5355,8 @@ class CypclassWrapperDefNode(CClassDefNode):
     def analyse_declarations(self, env):
         # > analyse declarations before inserting methods
         super(CypclassWrapperDefNode, self).analyse_declarations(env)
+        # > mark the wrapper type as such
+        self.entry.type.is_cyp_wrapper = 1
         # > associate the wrapper type to the wrapped type
         self.wrapped_cypclass.entry.type.wrapper_type = self.entry.type
         # > insert and analyse each method wrapper