Getting undefined reference , how to link during module building ?

[Ramesh Rajagopal <shmera@xxxxxxxxx>]

Hi Guys,
   I am trying to do the following but I am getting undefined reference error ?  

I have two modules lets say Module A & Module B. Module B defines a function called 
module_b_func() which got exported also. Then I compile module B and inserted into kernel using insmod. 

Then in module A I tried to call module B's function module_b_func(), When I tried to compile 
I am getting undefined reference to module_b_func(). How to link moduleB's function here. 

Do I need to give some options to the linker or how to compile ? 

The following is my Makefile contents :

obj-m := module_A.o

M=$(shell pwd)

all:
    make -C /lib/modules/$(shell uname -r)/build/ M=$(M) modules
clean:    
    rm -rf *.o *.ko
distclean:    
    rm -rf *.markers *.order *.symvers 
             
   
Thanks,
Ramesh.