the behavior of 'step over' is same as 'step in' in AGDI apntex_173

I have built one AGDI dlls for cortex-m3, when I run 'step over' of the debugger, it goes where as same as 'step in'. For example:

there are two functions invoked as below in c codes:

func_a(); func_b();

if current cursor is pointing to func_a(), so then I run 'step over' it should be go to next function as func_b(), but it steped into func_a().

Any body knows the reasons?

Thanks