Repro case! Re: GDB 10.1: Backtrace goes into infinite loop

[Paul Smith]

On Mon, 2021-02-01 at 22:21 -0500, Paul Smith via Gdb wrote:
> I've discovered that there's something wonky with the embedded Python
> interpreter and checking threads while pretty-printing stack
> variables.

More proof:

I rebuilt GDB 10.1 with this patch applied:

--- a/gdb/python/py-inferior.c
+++ b/gdb/python/py-inferior.c
@@ -394,7 +394,7 @@ infpy_threads (PyObject *self, PyObject *args)

   try
     {
-      update_thread_list ();
+      // update_thread_list ();
     }
   catch (const gdb_exception &except)
     {

Just to see, and this version of GDB works fine.

There's something unpleasant about invoking update_thread_list() while
we are attempting to pretty-print stack variables; it must mess with
some global state somewhere that doesn't expect to be messed with, at
that time.