Segfault in mp_obj_exception_add_traceback #17117
Description
Port, board and/or hardware
Unix
MicroPython version
master branch with taskgroup PR #8791, commit 32608f0; at first glance this seems to be related to async-error handling (obvious from the stack trace …) but not necessarily specific to the taskgroup stuff.
Reproduction
Currently somewhat involved, as in
- pull smurfix/moat
- update submodules
- go to
ext/micropython/ports/unixand build withDEBUG=1 STRIP= - run
pytest tests/micro/test_micro.py::test_iter_m ulimit -c unlimited- probably install some bits&pieces from the requirements in
pyproject.tomlif that fails - run
gdbon the resulting coredump
Expected behaviour
No crash.
I have added a very ugly workaround, see commit f7635bb in repo https://github.com/smurfix/micropython ("hack" branch) which appears to circumvent the problem with no ill effects. So far (I'm in the middle of refactoring my code rather aggressively). Not a real fix by any means but I have no idea where the error is ultimately coming from.
Observed behaviour
(gdb) fr 0
#0 0x000055a98ac3ee22 in mp_obj_exception_add_traceback (self_in=<optimized out>, file=1788,
line=291, block=138) at ../../py/objexcept.c:636
636 self->traceback_len += TRACEBACK_ENTRY_LEN;
(gdb) p self
$3 = (mp_obj_exception_t *) 0x55a98ace53c0 <native_base_init_wrapper_obj>
(gdb)
… which definitely isn't supposed to happen.
Additional Information
#0 0x000055a98ac3ee22 in mp_obj_exception_add_traceback (self_in=<optimized out>, file=1788,
line=291, block=138) at ../../py/objexcept.c:636
#1 0x000055a98ac518dd in mp_execute_bytecode (code_state=code_state@entry=0x7fce5a98bf30,
inject_exc=inject_exc@entry=0x0) at ../../py/vm.c:1434
#2 0x000055a98ac40275 in mp_obj_gen_resume (self_in=self_in@entry=0x7fce5a98bf20,
send_value=send_value@entry=0x6, throw_value=throw_value@entry=0x0,
ret_val=ret_val@entry=0x7ffed951d3f8) at ../../py/objgenerator.c:210
#3 0x000055a98ac36bb0 in mp_resume (self_in=0x7fce5a98bf20, send_value=0x6,
throw_value=throw_value@entry=0x0, ret_val=ret_val@entry=0x7ffed951d3f8)
at ../../py/runtime.c:1425
#4 0x000055a98ac53199 in mp_execute_bytecode (code_state=code_state@entry=0x7fce5a97b8d0,
inject_exc=inject_exc@entry=0x0) at ../../py/vm.c:1203
#5 0x000055a98ac40275 in mp_obj_gen_resume (self_in=self_in@entry=0x7fce5a97b8c0,
send_value=send_value@entry=0x6, throw_value=throw_value@entry=0x0,
ret_val=ret_val@entry=0x7ffed951d558) at ../../py/objgenerator.c:210
#6 0x000055a98ac36bb0 in mp_resume (self_in=0x7fce5a97b8c0, send_value=0x6,
throw_value=throw_value@entry=0x0, ret_val=ret_val@entry=0x7ffed951d558)
at ../../py/runtime.c:1425
...
#19 0x000055a98ac53199 in mp_execute_bytecode (code_state=code_state@entry=0x7fce5a97aeb0,
inject_exc=inject_exc@entry=0x0) at ../../py/vm.c:1203
#20 0x000055a98ac40275 in mp_obj_gen_resume (self_in=0x7fce5a97aea0,
send_value=<optimized out>, throw_value=throw_value@entry=0x0,
ret_val=ret_val@entry=0x7ffed951dba8) at ../../py/objgenerator.c:210
#21 0x000055a98ac40302 in gen_resume_and_raise (self_in=<optimized out>,
send_value=<optimized out>, throw_value=throw_value@entry=0x0,
raise_stop_iteration=raise_stop_iteration@entry=true) at ../../py/objgenerator.c:259
#22 0x000055a98ac4039c in gen_instance_send (self_in=<optimized out>,
send_value=<optimized out>) at ../../py/objgenerator.c:286
#23 0x000055a98ac3f7ea in fun_builtin_2_call (self_in=0x55a98ace3de0 <gen_instance_send_obj>,
n_args=<optimized out>, n_kw=<optimized out>, args=0x7fce5a919310) at ../../py/objfun.c:82
#24 0x000055a98ac3667e in mp_call_function_n_kw (
fun_in=0x55a98ace3de0 <gen_instance_send_obj>, n_args=2, n_kw=0, args=0x7fce5a919310)
at ../../py/runtime.c:726
#25 0x000055a98ac367eb in mp_call_method_n_kw (n_args=<optimized out>, n_kw=<optimized out>,
args=args@entry=0x7fce5a919308) at ../../py/runtime.c:742
#26 0x000055a98ac51d48 in mp_execute_bytecode (code_state=code_state@entry=0x7fce5a9192e0,
inject_exc=inject_exc@entry=0x0) at ../../py/vm.c:1042
#27 0x000055a98ac3faa5 in fun_bc_call (self_in=0x7fce5a9005a0, n_args=1, n_kw=0,
args=0x7ffed951dea0) at ../../py/objfun.c:295
...
#43 0x000055a98ac3faa5 in fun_bc_call (self_in=0x7fce5a8f5320, n_args=0, n_kw=0, args=0x0)
at ../../py/objfun.c:295
#44 0x000055a98ac3667e in mp_call_function_n_kw (fun_in=0x7fce5a8f5320,
n_args=n_args@entry=0, n_kw=n_kw@entry=0, args=args@entry=0x0) at ../../py/runtime.c:726
#45 0x000055a98ac366c4 in mp_call_function_0 (fun=<optimized out>) at ../../py/runtime.c:700
#46 0x000055a98ac97cf1 in execute_from_lexer (source_kind=source_kind@entry=3,
source=<optimized out>, input_kind=input_kind@entry=MP_PARSE_FILE_INPUT,
is_repl=is_repl@entry=false) at main.c:162
#47 0x000055a98ac97d54 in do_file (file=<optimized out>) at main.c:311
#48 0x000055a98ac983f8 in main_ (argc=argc@entry=2, argv=argv@entry=0x7ffed951e8a8)
at main.c:740
#49 0x000055a98ac985e1 in main (argc=2, argv=0x7ffed951e8a8) at main.c:491
Code of Conduct
Yes, I agree