VS2013, C++: Unknown "thread X exited with code 0"

Question

I am developing some Qt application on VS2013. One day I turned my attention to the fact that Qt runtime libs perform strange CPU consumptive actions. Firstly, I decided that it occurs in Qt debug libs only and turned my debug configuration to use Qt release libs. But I am still confused when observing in VS output window, at the middle of debugging my application, such prints: The thread 0xXXXX has exited with code 0 (0x0) . I don't understand which thread was finished. How can I detect what thread is hidden behind this thread ID = 0xXXXX once this thread has already finished?

UPDATE (clarification) In my question I meant: 1. Is it possible to get some information about a thread ID appeared in such VS print 2. Does somebody know what Qt may execute in such hidden threads?

Answer 1

Different libraries may create worker threads for various purposes.

If you want to investigate this further do the following in VS IDE:

1. Debug -> Break All. This will stop all threads in the process
2. Debug -> Windows -> Threads to get list of all threads.

By examining call stack of threads you may get an idea of its purpose.