I just spent many hours chasing down a compiler arg that another project had set that prevented me from stepping into the library in the debugger in QtCreator (the library itself does not use Qt, nor does my application).

The argument was `-ffile-prefix-map` but my complaint/suggestion revolves around the lack of a message coming out in the Global Debugger Log.

In the attached files there are two separate projects: one library and one application.

With `lib/CMakeLists.txt` line 6 commented out everything works great.  However, with it in, when you try to step into `real_function()` the debugger is unable to find the source code.

That's not the debugger's fault, but when I do this exercise with the command-line gdb, there's a nice visible "No such file or directory." message printed to the console.

However, I don't see (I've looked hard, I promise!) any comparable output in any of the pertinent panes in QtCreator.  I assume it's getting filtered out somehow, but maybe it's not being produced either??

Anyway, it may be very helpful to others walking this particular path if QtCreator was able to give that kind of message to the user (like the command-line gdb does).