Strange first chance exception when running the compiler in Qt Creator

Gmember

Hello,

I am testing my Qt Widgets application. It runs fine (both the debug build and the release build) and doesn't throw any exception. However, if I run the debugger from Qt Creator (with F5), I get a first chance exception when the application starts:

:-1: error: Exception at 0x7fff13ab7788, code: 0xa1a01db1: , flags=0x0 (first chance)

and another one when the application exits:

:-1: error: Exception at 0x7fff13ab7788, code: 0xa1a01db2: , flags=0x0 (first chance)

Despite these messages though, the program runs fine. I looked around and I could not find an explanation.

I am not including any source code, since the application is very large and uses many libraries, so I would need to know how to narrow down the portion of code that is causing the problem.

I am tried with Qt 5.6.1, Qt 5.7.0 and the compilers MSVC2013 and MSVC2015 and it behaves in the same way every time.

Chris Hennes

Two questions that might help you narrow it down: First, do you have your debugger set to break on C++ exceptions? Second, do you have the "Ignore first change access violations" option set?

Gmember

Hi, thank you for your reply. Both those options were disabled. I still get the same messages if I select either one or both of those options. Could you explain in what cases those settings may be helpful?

Chris Hennes

If you turn on the "Break on C++ Exceptions" and run in the debugger, I expect it to stop on that exception and show you the call stack, which will usually help you figure out what is causing the issue.