I get the following backtrace when executing a certain (largish...) python script

(gdb) bt full
#0  0x0810c457 in typy_fields (self=0xb7a02920, args=0x0)
    at ../../archer/gdb/python/py-type.c:172
        dict = (PyObject *) 0xb7a24420
        result = (PyObject *) 0xb791ccec
        i = 0
        type = (struct type *) 0x8a9a47c
#1  0xb7d01cef in PyEval_EvalFrameEx () from /usr/lib/libpython2.6.so.1.0
No symbol table info available.
#2  0xb7d02b4f in PyEval_EvalFrameEx () from /usr/lib/libpython2.6.so.1.0
No symbol table info available.
#3  0xb7d02b4f in PyEval_EvalFrameEx () from /usr/lib/libpython2.6.so.1.0
No symbol table info available.
#4  0xb7d02b4f in PyEval_EvalFrameEx () from /usr/lib/libpython2.6.so.1.0
No symbol table info available.
#5  0xb7d02b4f in PyEval_EvalFrameEx () from /usr/lib/libpython2.6.so.1.0
No symbol table info available.
#6  0xb7d03910 in PyEval_EvalCodeEx () from /usr/lib/libpython2.6.so.1.0
No symbol table info available.
#7  0xb7c8987a in ?? () from /usr/lib/libpython2.6.so.1.0
No symbol table info available.
#8  0xb7c5998c in PyObject_Call () from /usr/lib/libpython2.6.so.1.0
No symbol table info available.
#9  0xb7c6a7a8 in ?? () from /usr/lib/libpython2.6.so.1.0
No symbol table info available.
#10 0xb7c5998c in PyObject_Call () from /usr/lib/libpython2.6.so.1.0
No symbol table info available.
#11 0xb7c5d1cb in PyObject_CallMethodObjArgs () from /usr/lib/libpython2.6.so.1.0
No symbol table info available.
#12 0x0810582e in cmdpy_function (command=0x8865c70, args=0x8793393 "1 local.f", 
    from_tty=1) at ../../archer/gdb/python/py-cmd.c:142
        argobj = <value optimized out>
        ttyobj = (PyObject *) 0xb7e29ff4
        result = <value optimized out>
        cleanup = (struct cleanup *) 0x0
#13 0x08098500 in execute_command (p=0x879339b "f", from_tty=1)
    at ../../archer/gdb/top.c:453
        arg = 0x8793393 "1 local.f"
        c = (struct cmd_list_element *) 0x8865c70
        flang = <value optimized out>
        line = 0x8793390 "bb 1 local.f"
        warned = 0
#14 0x08176518 in command_handler (command=0x8793390 "bb 1 local.f")
    at ../../archer/gdb/event-top.c:511
        stdin_is_tty = <value optimized out>
        time_at_cmd_start = 588036
        space_at_cmd_start = 0
---Type <return> to continue, or q <return> to quit---
#15 0x08177282 in command_line_handler (rl=0x8c30c40 "bb 1 local.f")
    at ../../archer/gdb/event-top.c:735
        p = 0x8865d3c ""
        p1 = 0x8865d30 "bb 1 local.f"
        repeat = 1
        linebuffer = 0x8865d30 "bb 1 local.f"
        linelength = 80
#16 0x0823f255 in rl_callback_read_char () at ../../archer/readline/callback.c:205
        line = 0x8c30c40 "bb 1 local.f"
        eof = <value optimized out>
        jcode = <value optimized out>
        olevel = {{__jmpbuf = {0, 138207068, 138183516, -1078808152, 457934318, 
      999434369}, __mask_was_saved = 1, __saved_mask = {__val = {
        0 <repeats 32 times>}}}}
#17 0x0817666b in rl_callback_read_char_wrapper (client_data=0x0)
    at ../../archer/gdb/event-top.c:178
No locals.
#18 0x08175b34 in handle_file_event (data={ptr = 0x0, integer = 0})
    at ../../archer/gdb/event-loop.c:812
        file_ptr = (file_handler *) 0x88419a8
        mask = <value optimized out>
        error_mask_returned = 0
#19 0x081752fb in process_event () at ../../archer/gdb/event-loop.c:394
        event_ptr = <value optimized out>
        proc = (event_handler_func *) 0x8175ab0 <handle_file_event>
        data = {ptr = 0x0, integer = 0}
#20 0x08176214 in gdb_do_one_event (data=0x0) at ../../archer/gdb/event-loop.c:459
        current = 3
        event_source_head = 0
#21 0x081703cb in catch_errors (func=0x8175fc0 <gdb_do_one_event>, func_args=0x0, 
    errstring=0x82e05c2 "", mask=6) at ../../archer/gdb/exceptions.c:510
        val = 0
        exception = {reason = 0, error = GDB_NO_ERROR, message = 0x0}
#22 0x080faa7a in tui_command_loop (data=0x0)
    at ../../archer/gdb/tui/tui-interp.c:153
        result = -1215232976
#23 0x08170ac4 in current_interp_command_loop () at ../../archer/gdb/interps.c:291