return (unsigned short)csum_fold(skb_checksum(skb, 0, skb->len, skb->csum)); 
return __skb_checksum_complete(skb); 
static __inline__ int __tcp_checksum_complete(struct sk_buff *skb){	return (unsigned short)csum_fold(skb_checksum(skb, 0, skb->len, skb->csum));}
4520	/local/tlutelli/issta_data/temp/c/2005_temp/2005/4520/fb286bb2990a107009dbf25f6ffebeb7df77f9be/tcp.h/buggy/include/net/tcp.h