subroutine function interface - debug options

dear all,

I have a problem with my program. When I compile it with:

ifort -r8 *.f90 -lmkl_blas95_lp64 -lmkl_lapack95_lp64 -mkl=sequential -CB

I have no problem and the results are correct, but of course the program results very slow.

On the other hand when I compile it without -CB I do not get exact results.

I would like to ask some questions:

1) How I can understand if my subroutine\functions calls are correct

2) Is there any way to correctly write a subroutine\functions? Now I am using all subroutine in module or interface

3)is there any compiler otions to find out the error?

4)is it a compiler bugs?

Thanks a lots