I’ve been having strange problems with Qt4 applications and GDB. I can’t debug any Qt4 app in either Eclipse or KDevelop. See this thread on the qt-interest list. The error I get:

Cannot insert breakpoint 0.
Error accessing memory address 0x0: Input/output error.

Running GDB from the command line on the binary works fine. I just found that NetBeans 6.0 with the C++ plugin works fine as well. I wonder what’s wrong with Eclipse and KDevelop. Could be the way they try to interface with GDB.