Trouble using debug-core-dump

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  1. I am trying to debug a core dump
  2. In my attempt to do this I am running mos version Version: 2.20.0 but am using 2.15.0 as my target build
  3. I am receiving the following error when the debug-core-dump tool
Using core ...
Core dump by ...
Using ELF file at: /home/matt/...
Using Docker image:
Running docker run --rm -i --tty=true -v .../fw.elf -v /home/matt/.../...-esp8266-20220201-132804.334526996:/core -v /home/matt/../..:/home/matt/../ bash -c /usr/local/bin/ --rom=/opt/Espressif/rom/rom.bin --rom_addr=0x40000000 /fw.elf /core & $MGOS_TARGET_GDB /fw.elf -ex 'target remote' -ex 'set confirm off' -ex bt
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Reading symbols from /fw.elf...Waiting for gdb on 1234
Found core at 23 - 133118
Mapping DRAM: 98304 @ 0x3ffe8000
Remote debugging using
Mapping /opt/Espressif/rom/rom.bin at 0x40000000
Mapping /fw.elf .data: 2760 @ 0x3ffe8000
Mapping /fw.elf .rodata: 8 @ 0x3ffe8ac8
Mapping /fw.elf .bss: 31904 @ 0x3ffe8ad0
Mapping /fw.elf .text: 29497 @ 0x40100000
Mapping /fw.elf .irom0.text: 823807 @ 0x40200010
Loaded core dump from last snippet in  /core
Exception happened during processing of request from ('', 57272)
Traceback (most recent call last):
  File "/usr/lib/python3.6/", line 317, in _handle_request_noblock
    self.process_request(request, client_address)
  File "/usr/lib/python3.6/", line 348, in process_request
    self.finish_request(request, client_address)
  File "/usr/lib/python3.6/", line 361, in finish_request
    self.RequestHandlerClass(request, client_address, self)
  File "/usr/lib/python3.6/", line 696, in __init__
  File "/usr/local/bin/", line 211, in handle
    self._curtask = core.tasks.get(tid)
AttributeError: 'Core' object has no attribute 'tasks'
Remote connection closed
No stack.

Any help would be sincerely appreciated !


It looks like there is a bug in 2.17.0 (which you are using). I don’t know if it’s in the sdk or in mongoose-os.

#include "mgos.h"

static void timer_cb(void *arg) {
  static bool s_tick_tock = false;
  static int count = 5;
  LOG(LL_INFO, ("%s uptime: %.2lf, RAM: %lu, %lu free, count: %d",
                (s_tick_tock ? "Tick" : "Tock"), mgos_uptime(),
                (unsigned long) mgos_get_heap_size(),
                (unsigned long) mgos_get_free_heap_size(), count));
  s_tick_tock = !s_tick_tock;
#ifdef LED_PIN

  if (count == 0) {
    count = 5;
    int *val = (int *) arg;
    LOG(LL_INFO, ("val: %d", *val));
  (void) arg;

enum mgos_app_init_result mgos_app_init(void) {
#ifdef LED_PIN
  mgos_gpio_setup_output(LED_PIN, 0);
  mgos_set_timer(1000 /* ms */, MGOS_TIMER_REPEAT, timer_cb, NULL);

This example triggers a core dump and when analyzed gives the same result as yours when built for 2.17.0 and a correct trace when built with >= 2.18.0.

Thank you for the helpful advice @nliviu !

Please excuse my ignorance in this matter, how does one see that I am using version 2.17.0?

mos version returns

The Mongoose OS command line tool
Version: 2.20.0
Build ID: 20211215-002601/2.20.0-g0278853
Update channel: release

Further my mos.yml shows the following target

libs_version: 2.15.0
modules_version: 2.15.0
mongoose_os_version: 2.15.0

Thank you again :slight_smile:

I browsed the previous versions of mongoose-os and found the sdk version esp8266-build:2.2.1-1.5.0-r5 in 2.17.0.
Apparently it has been in use for some time :slight_smile:

Ah I see !

Looking at version 2.15.0 indicates the same sdk version.

Thank you for the insight :slight_smile: