Abstract: In a method for off-line analyzing crashed programs, a simulator of a debugger is made to enter into a running state, and set breakpoints in the running state. Register and memory signals are separated from a dump signal outputted by a platform during crash. The debugger is used to replace, at the breakpoints, register and memory signals of the simulator originally in the running state with the register and memory signals separated from the dump signal. A debugging signal in the running state is replaced with a debugging signal during crash. The debugger is used to analyze reasons of crash based on the debugging, register, and memory signals after replacement. By separating the register and memory signals from the dump signals outputted by the platform during crash without involving any OS signal, there is no need to modify the platform and the GDB debugger when analyzing the reasons of crash.