# std::thread 中的异常会丢失调用栈
(金庆的专栏 2019.9)
主函数中的异常生成core文件能看到调用栈，
但是 std::thread 子线程中的异常生成 core 文件的调用栈如下：
```
Program received signal SIGABRT, Aborted.
[Switching to Thread 0x7f18f00ab700 (LWP 32340)]
0x00007f19007335f7 in raise () from /lib64/libc.so.6
(gdb) bt
#0 0x00007f19007335f7 in raise () from /lib64/libc.so.6
#1 0x00007f1900734ce8 in abort () from /lib64/libc.so.6
#2 0x00007f19010379d5 in __gnu_cxx::__verbose_terminate_handler() () from /lib64/libstdc++.so.6
#3 0x00007f1901035946 in ?? () from /lib64/libstdc++.so.6
#4 0x00007f1901035973 in std::terminate() () from /lib64/libstdc++.so.6
#5 0x00007f190108c2b5 in ?? () from /lib64/libstdc++.so.6
#6 0x00007f19012e7dc5 in start_thread () from /lib64/libpthread.so.0
#7 0x00007f19007f41cd in clone () from /lib64/libc.so.6
(gdb)
```
调用栈丢失使调试无法找到问题点。
据说 GCC 8 修正了该问题。
参考：
* [C++ uncaught exception in worker thread](https://stackoverflow.com/questions/48535100/c-uncaught-exception-in-worker-thread)
* [Bug 55917 - Impossible to find/debug unhandled exceptions in an std::thread](https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55917)