Help needed....

Hi there,

I am trying to do a porject on Baugh_Wooley multiplier in sequential circuit.

With the last 1 weeks real hard work i came to end up with this code.

but now when i checked syntax i got the following error.

I dont know how to solve it....please help me....:(

I am attching the top level code also.

I am really helpless. I tried a lot of ways...:(

thanks in advance.