Fix a refcounting bug in the new @total_ordering decorator.

See https://github.com/cython/cython/pull/3626

Cython/Compiler/ModuleNode.py

@@ -2148,11 +2148,11 @@ class ModuleNode(Nodes.Node, Nodes.BlockNode):
                     # Implement the and/or check with an if.
                     if comp_op == '&&':
                         code.putln("if (%s order_res) {" % ('!!' if invert_comp else '!'))
-                        code.putln("ret = Py_False;")
+                        code.putln("ret = __Pyx_NewRef(Py_False);")
                         code.putln("} else {")
                     elif comp_op == '||':
                         code.putln("if (%s order_res) {" % ('!' if invert_comp else ''))
-                        code.putln("ret = Py_True;")
+                        code.putln("ret = __Pyx_NewRef(Py_True);")
                         code.putln("} else {")
                     else:
                         raise AssertionError('Unknown op %s' % (comp_op, ))

tests/run/exttype_total_ordering.pyx

@@ -39,6 +39,9 @@ def test_all_comp(cls):
                 expected = func(left.value, right.value)
                 try:
                     result = func(left, right)
+                    # repeat to rule out deallocation bugs (and assert determinism)
+                    for _ in range(10):
+                        assert result == func(left, right)
                 except TypeError:
                     print("TypeError:", left.value, comp, right.value)
                     succeeded = False