[Python-Dev] Crash in new "trashcan" mechanism.

[Christian Tismer]

Mark,

I know you are very busy. But I have no chance to build
a debug version, and probably there are more differences.

Can you perhaps try Vlad's patch?
and tell me if the outcome changes? This would give me
much more insight.
The change affects the macros and the function _PyTrash_deposit_object
which now must report an error via the return value.

The macro code should be:

#define Py_TRASHCAN_SAFE_BEGIN(op) \
        { \
                ++_PyTrash_delete_nesting; \
                if (_PyTrash_delete_nesting < PyTrash_UNWIND_LEVEL || \
                    _PyTrash_deposit_object((PyObject*)op) != 0) {    \
#define Py_TRASHCAN_SAFE_END(op) \
                ;} \
                --_PyTrash_delete_nesting; \
                if (_PyTrash_delete_later && _PyTrash_delete_nesting <= 0) \
                        _PyTrash_destroy_list(); \
        } \

And the _PyTrash_deposit_object code should be (untested):

int
_PyTrash_deposit_object(op)
	PyObject *op;
{
	PyObject *error_type, *error_value, *error_traceback;

	if (PyThreadState_GET() != NULL)
	    PyErr_Fetch(&error_type, &error_value, &error_traceback);

	if (!_PyTrash_delete_later)
		_PyTrash_delete_later = PyList_New(0);
	if (_PyTrash_delete_later)
		return PyList_Append(_PyTrash_delete_later, (PyObject *)op);
	else
		return -1;

	if (PyThreadState_GET() != NULL)
	    PyErr_Restore(error_type, error_value, error_traceback);
	return 0;
}


The result of this would be really enlighting :-)

ciao - chris


Vladimir Marangozov wrote:
> 
> Of course, this
> 
> Vladimir Marangozov wrote:
> >
> > to:
> >
> > #define Py_TRASHCAN_SAFE_BEGIN(op) \
> >         { \
> >                 ++_PyTrash_delete_nesting; \
> >                 if (_PyTrash_delete_nesting >= PyTrash_UNWIND_LEVEL && \
> >                     _PyTrash_deposit_object((PyObject*)op) != 0) {    \
> >
> 
> was meant to be this:
> 
> #define Py_TRASHCAN_SAFE_BEGIN(op) \
>         { \
>                 ++_PyTrash_delete_nesting; \
>                 if (_PyTrash_delete_nesting < PyTrash_UNWIND_LEVEL || \
>                     _PyTrash_deposit_object((PyObject*)op) != 0) {    \
> 
> --
>        Vladimir MARANGOZOV          | Vladimir.Marangozov@inrialpes.fr
> http://sirac.inrialpes.fr/~marangoz | tel:(+33-4)76615277 fax:76615252
> 
> _______________________________________________
> Python-Dev mailing list
> Python-Dev@python.org
> http://www.python.org/mailman/listinfo/python-dev

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