New issue 1874: Misleading RPython error message: setting forbidden attribute https://bitbucket.org/pypy/pypy/issue/1874/misleading-rpython-error-message-... Edd Barrett: Hi, I think I know what this error message means: ``` [translation:ERROR] NoSuchAttrError: [translation:ERROR] [translation:ERROR] setting forbidden attribute 'php_interp' on <ClassDef 'hippy.objects.instanceobject.W_InstanceObject'> [translation:ERROR] [translation:ERROR] [translation:ERROR] v1036 = getattr(this_0, ('php_interp')) [translation:ERROR] [translation:ERROR] In <FunctionGraph of (hippy.module.pypy_bridge.php_wrappers:367)wpy_exc_getMessage at 0x40cf49c0>: [translation:ERROR] Happened at file hippy/module/pypy_bridge/php_wrappers.py line 369 [translation:ERROR] [translation:ERROR] ==> py_space = this.php_interp.pyspace [translation:ERROR] msg = py_space.str_w(py_space.str(this.w_py_exn.get_w_value(py_space))) [translation:ERROR] return this.interp.space.wrap(msg) [translation:ERROR] [translation:ERROR] Known variable annotations: [translation:ERROR] this_0 = SomeInstance(can_be_None=False, classdef=hippy.objects.instanceobject.W_InstanceObject) [translation:ERROR] [translation:ERROR] Processing block: [translation:ERROR] block@3 is a <class 'rpython.flowspace.flowcontext.SpamBlock'> [translation:ERROR] in (hippy.module.pypy_bridge.php_wrappers:367)wpy_exc_getMessage [translation:ERROR] containing the following operations: [translation:ERROR] v1036 = getattr(this_0, ('php_interp')) [translation:ERROR] v1037 = getattr(v1036, ('pyspace')) [translation:ERROR] v1038 = getattr(v1037, ('str_w')) [translation:ERROR] v1039 = getattr(v1037, ('str')) [translation:ERROR] v1040 = getattr(this_0, ('w_py_exn')) [translation:ERROR] v1041 = getattr(v1040, ('get_w_value')) [translation:ERROR] v1042 = simple_call(v1041, v1037) [translation:ERROR] v1043 = simple_call(v1039, v1042) [translation:ERROR] v1044 = simple_call(v1038, v1043) [translation:ERROR] v1045 = getattr(this_0, ('interp')) [translation:ERROR] v1046 = getattr(v1045, ('space')) [translation:ERROR] v1047 = getattr(v1046, ('wrap')) [translation:ERROR] v1048 = simple_call(v1047, v1044) [translation:ERROR] --end-- ``` It means that RPython has been unable to guarantee the existence of `this.php_interp.pyspace`. It has nothing to do with setting any 'forbidden' attribute. Right?