Re: [PATCH v9 06/10] python: Add clear() to gdb.Record.

[Tom Tromey <tom@tromey.com>]

>>>>> Felix Willgerodt via Gdb-patches <gdb-patches@sourceware.org> writes:

> This function allows to clear the trace data from python, forcing to
> re-decode the trace for successive commands.
> This will be used in future ptwrite patches, to trigger re-decoding when
> the ptwrite filter changes.

> +PyObject *
> +recpy_bt_clear (PyObject *self, PyObject *args)
> +{
> +  const recpy_record_object * const record = (recpy_record_object *) self;
> +  thread_info *const tinfo = record->thread;

Normally in the Python layer, some care must be taken to ensure that
something sensible happens when a Python object outlives some underlying
gdb object.  That is why some types have an 'is_valid' method and why
there are the various *_REQUIRE_VALID macros.

It isn't a problem with this patch per se but it seems to me that this
code does not handle this situation properly.

Tom