When I debug certain programs via "Start Debugging", the debugger will reach the first breakpoint. If I hit "Step Over" or anything from that point, Qt creator will hang and the entire system will become unresponsive. My only choice is to go to runlevel 1 and kill qtcreator. Other programs have worked fine. What I have found with the troublesome program is that it has a try-catch block. If I set a breakpoint within the try block, the debugger hangs anytime I try to move from that breakpoint. Once I remove the try and catch statements, but keep the code within the try block, the debugger works fine.