Undocumented gdb Version (> 11.1) Requirements for Python Attach Mode

[realaslam786]

Type: Bug

Behaviour

Expected vs. Actual

Minimum gdb version requirements need to be clearly specified.

Steps to reproduce:

Diagnostic data

• Python version (& distribution if applicable, e.g. Anaconda): 3.9.18
• Type of virtual environment used (e.g. conda, venv, virtualenv, etc.): Unknown
• Value of the python.languageServer setting: Default

There are undocumented (implicit) requirements on having gdb version > 11.1 available for Python Attach debug configuration to work.

1. The requirement to have a gdb installation available in the Path is not documented as the pre-requisites for the extension. A gdb in Path is needed for the Python Attach mode debug configurations to work.

2. The minimum gdb requirement is not specified. The extension fails to attach to an existing process with gdb version 11.1. However, it has been successfully tested with gdb version 12.1. With gdb version 11.1. The following is part of the error logs shown in the Debug Console for gdb version 11.1.

Attach to PID failed.

--- Starting attach to pid: xx---
[New LWP xx]
[New LWP xx]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
0x00007f4c08f5170c in pthread_cond_wait@@GLIBC_2.3.2 () from /lib64/libpthread.so.0
The target architecture is set to "auto" (currently "i386:x86-64").
Couldn't write extended state status: Bad address.
No symbol "DoAttach" in current context.
[Inferior 1 (process 136643) detached]
E+00003.400: Code injection into PID=136643 failed

Traceback (most recent call last):
File "/.../ms-python.python-2023.20.0/pythonFiles/lib/python/debugpy/adapter/../../debugpy/../debugpy/server/cli.py", line 391, in attach_to_pid
add_code_to_python_process.run_python_code(
File "/.../ms-python.python-2023.20.0/pythonFiles/lib/python/debugpy/_vendored/pydevd/pydevd_attach_to_process/add_code_to_python_process.py", line 471, in run_python_code_linux
subprocess.check_call(' '.join(cmd), shell=True, env=env)
File "/...//python3.9/subprocess.py", line 373, in check_call
raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command 'gdb --nw --nh --nx --pid 136643 --batch --eval-command='set scheduler-locking off' --eval-command='set architecture auto' --eval-command='call (void*)dlopen("/.../ms-python.python-2023.20.0/pythonFiles/lib/python/debugpy/_vendored/pydevd/pydevd_attach_to_process/attach_linux_amd64.so", 2)' --eval-command='sharedlibrary attach_linux_amd64' --eval-command='call (int)DoAttach(0, "import codecs;import json;import sys;decode = lambda s: codecs.utf_8_decode(bytearray(s))[0] if s is not None else None;script_dir = decode ...


XXX

User Settings

languageServer: "Pylance"

Extension version: 2023.16.0
VS Code version: Code 1.85.0 (af28b32d7e553898b2a91af498b1fb666fdebe0c, 2023-12-06T20:48:09.019Z)
OS version: Windows_NT x64 10.0.22621
Modes:
Remote OS version: Linux x64 5.14.21-150400.22-default
Remote OS version: Linux x64 5.14.21-150400.22-default

[xsank]

gdb 12.1 with the same problem...

[New LWP 483611]
[New LWP 483615]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
__futex_abstimed_wait_common64 (private=0, cancel=true, abstime=0x0, op=393, expected=0, futex_word=0x55b7d5e37ab0) at ./nptl/futex-internal.c:57
57	./nptl/futex-internal.c: No such file or directory.
The target architecture is set to "auto" (currently "i386:x86-64").
Couldn't write extended state status: Bad address.
No symbol "DoAttach" in current context.
[Inferior 1 (process 473713) detached]
E+00004.804: Code injection into PID=473713 failed:
             
             Traceback (most recent call last):
               File "/root/.vscode-server/extensions/ms-python.debugpy-2025.8.0-linux-x64/bundled/libs/debugpy/adapter/../../debugpy/../debugpy/server/cli.py", line 461, in attach_to_pid
                 add_code_to_python_process.run_python_code(
               File "/root/.vscode-server/extensions/ms-python.debugpy-2025.8.0-linux-x64/bundled/libs/debugpy/_vendored/pydevd/pydevd_attach_to_process/add_code_to_python_process.py", line 480, in run_python_code_linux
                 subprocess.check_call(" ".join(cmd), shell=True, env=env)
               File "/usr/lib/python3.10/subprocess.py", line 369, in check_call
                 raise CalledProcessError(retcode, cmd)
             subprocess.CalledProcessError: Command 'gdb --nw --nh --nx --pid 473713 --batch --eval-command='set scheduler-locking off' --eval-command='set architecture auto' --eval-command='call (void*)dlopen("/root/.vscode-server/extensions/ms-python.debugpy-2025.8.0-linux-x64/bundled/libs/debugpy/_vendored/pydevd/pydevd_attach_to_process/attach_linux_amd64.so", 2)' --eval-command='sharedlibrary attach_linux_amd64' --eval-command='call (int)DoAttach(0, "import codecs;import json;import sys;decode = lambda s: codecs.utf_8_decode(bytearray(s))[0] if s is not None else None;script_dir = decode([47, 114, 111, 111, 116, 47, 46, 118, 115, 99, 111, 100, 101, 45, 115, 101, 114, 118, 101, 114, 47, 101, 120, 116, 101, 110, 115, 105, 111, 110, 115, 47, 109, 115, 45, 112, 121, 116, 104, 111, 110, 46, 100, 101, 98, 117, 103, 112, 121, 45, 50, 48, 50, 53, 46, 56, 46, 48, 45, 108, 105, 110, 117, 120, 45, 120, 54, 52, 47, 98, 117, 110, 100, 108, 101, 100, 47, 108, 105, 98, 115, 47, 100, 101, 98, 117, 103, 112, 121, 47, 97, 100, 97, 112, 116, 101, 114, 47, 46, 46, 47, 46, 46, 47, 100, 101, 98, 117, 103, 112, 121, 47, 46, 46, 47, 100, 101, 98, 117, 103, 112, 121, 47, 115, 101, 114, 118, 101, 114]);setup = json.loads(decode([123, 34, 109, 111, 100, 101, 34, 58, 32, 34, 99, 111, 110, 110, 101, 99, 116, 34, 44, 32, 34, 97, 100, 100, 114, 101, 115, 115, 34, 58, 32, 91, 34, 49, 50, 55, 46, 48, 46, 48, 46, 49, 34, 44, 32, 53, 53, 50, 56, 55, 93, 44, 32, 34, 119, 97, 105, 116, 95, 102, 111, 114, 95, 99, 108, 105, 101, 110, 116, 34, 58, 32, 102, 97, 108, 115, 101, 44, 32, 34, 108, 111, 103, 95, 116, 111, 34, 58, 32, 110, 117, 108, 108, 44, 32, 34, 97, 100, 97, 112, 116, 101, 114, 95, 97, 99, 99, 101, 115, 115, 95, 116, 111, 107, 101, 110, 34, 58, 32, 34, 101, 102, 54, 102, 56, 54, 57, 102, 48, 98, 56, 55, 100, 49, 99, 51, 53, 101, 98, 52, 55, 50, 53, 55, 56, 51, 52, 53, 100, 54, 54, 101, 102, 55, 98, 52, 50, 98, 100, 100, 52, 101, 55, 48, 49, 50, 101, 97, 102, 101, 48, 54, 99, 51, 49, 101, 98, 101, 99, 56, 49, 53, 56, 97, 34, 125]));sys.path.insert(0, script_dir);import attach_pid_injected;del sys.path[0];attach_pid_injected.attach(setup);", 0)'' returned non-zero exit status 1.
             
             Stack where logged:
               File "/usr/lib/python3.10/runpy.py", line 196, in _run_module_as_main
                 return _run_code(code, main_globals, None,
               File "/usr/lib/python3.10/runpy.py", line 86, in _run_code
                 exec(code, run_globals)
               File "/root/.vscode-server/extensions/ms-python.debugpy-2025.8.0-linux-x64/bundled/libs/debugpy/adapter/../../debugpy/__main__.py", line 71, in <module>
                 cli.main()
               File "/root/.vscode-server/extensions/ms-python.debugpy-2025.8.0-linux-x64/bundled/libs/debugpy/adapter/../../debugpy/../debugpy/server/cli.py", line 501, in main
                 run()
               File "/root/.vscode-server/extensions/ms-python.debugpy-2025.8.0-linux-x64/bundled/libs/debugpy/adapter/../../debugpy/../debugpy/server/cli.py", line 468, in attach_to_pid
                 log.reraise_exception("Code injection into PID={0} failed:", pid)
               File "/root/.vscode-server/extensions/ms-python.debugpy-2025.8.0-linux-x64/bundled/libs/debugpy/adapter/../../debugpy/../debugpy/common/log.py", line 222, in reraise_exception
                 _exception(format_string, *args, **kwargs)
             

Traceback (most recent call last):
  File "/usr/lib/python3.10/runpy.py", line 196, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "/usr/lib/python3.10/runpy.py", line 86, in _run_code
    exec(code, run_globals)
  File "/root/.vscode-server/extensions/ms-python.debugpy-2025.8.0-linux-x64/bundled/libs/debugpy/adapter/../../debugpy/__main__.py", line 71, in <module>
    cli.main()
  File "/root/.vscode-server/extensions/ms-python.debugpy-2025.8.0-linux-x64/bundled/libs/debugpy/adapter/../../debugpy/../debugpy/server/cli.py", line 501, in main
    run()
  File "/root/.vscode-server/extensions/ms-python.debugpy-2025.8.0-linux-x64/bundled/libs/debugpy/adapter/../../debugpy/../debugpy/server/cli.py", line 468, in attach_to_pid
    log.reraise_exception("Code injection into PID={0} failed:", pid)
  File "/root/.vscode-server/extensions/ms-python.debugpy-2025.8.0-linux-x64/bundled/libs/debugpy/adapter/../../debugpy/../debugpy/server/cli.py", line 461, in attach_to_pid
    add_code_to_python_process.run_python_code(
  File "/root/.vscode-server/extensions/ms-python.debugpy-2025.8.0-linux-x64/bundled/libs/debugpy/_vendored/pydevd/pydevd_attach_to_process/add_code_to_python_process.py", line 480, in run_python_code_linux
    subprocess.check_call(" ".join(cmd), shell=True, env=env)
  File "/usr/lib/python3.10/subprocess.py", line 369, in check_call
    raise CalledProcessError(retcode, cmd)

env

GNU gdb (Ubuntu 12.1-0ubuntu1~22.04.2) 12.1
Copyright (C) 2022 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

[rchiodo]

This will all be a moot point once 3.14 ships as it handles attach for us.

[xsank]

This will all be a moot point once 3.14 ships as it handles attach for us.

What?

[rchiodo]

This PEP here:
https://peps.python.org/pep-0768/