Is it possible to debug deadlock with codelldb?

[zchrissirhcz]

Hi, vscode-lldb developers and contributors

I'm recently learning C++ multithreading programming, and notice gdb can debug deadlock (or some deadlock case, as I know less). I do a simple try but failed to find vscode-lldb support deadlock debug.

Example deadlock program

#include <mutex>
#include <thread>
#include <chrono>
#include <iostream>

using std::mutex;
using std::lock_guard;
using std::thread;

mutex _mutex1;
mutex _mutex2;
int data1;
int data2;

int do_work_1()
{
    std::cout << "thread function do_work_1 start" << std::endl;
    //{
        lock_guard<mutex> locker1(_mutex1);
        data1++;
        std::this_thread::sleep_for(std::chrono::seconds(1));
    //}

    //{
        lock_guard<mutex> locker2(_mutex2);
        data2++;
        std::cout << "thread function do_work_1 end" << std::endl;
    //}
    return 0;
}

int do_work_2()
{
    std::cout << "thread function do_work_2 start" << std::endl;
    lock_guard<mutex> locker2(_mutex2);
    data2++;
    std::this_thread::sleep_for(std::chrono::seconds(1));
    lock_guard<mutex> locker1(_mutex1);

    data1++;
    std::cout << "thread function do_work_2 end" << std::endl;
    return 0;
}

int main()
{
    thread t1(do_work_1);
    thread t2(do_work_2);
    t1.join();
    t2.join();
    std::cout <<"thread run end" << std::endl;

    return 0;
}

gdb debug dead lock steps

with steps like:

gdb   ./a.out
$gdb  r
$gdb # now get stuck
$gdb Ctrl+C   # press Control +C key.  Don't know if codelldb can do same thing?
$gdb info threads
$gdb t 1  # switch to the first thread
$gdb blablabla

[zchrissirhcz]

Let me answer this question by myself.
The codelldb vscode plugin, when debugging C/C++, providing a lldb command console.
Just type pro signal SIGHUP, get same effect as "Ctrl+C" key. (Yes, for lldb).

For gdb, use signal SIGHUP.