freeBSD and Complieation Error

I am compiling squid with the following options

/configure --enable-dlmalloc

It gave me no error on Linux but on FreeBSD its Give error .?

any Comment or Help

gcc -g -Wall -I../include -I../include -c dlmalloc.c
dlmalloc.c:796: conflicting types for `sbrk'
/usr/include/unistd.h:179: previous declaration of `sbrk'
*** Error code 1

Stop in /root/squid/squid-2.3.STABLE3/lib.
*** Error code 1

Stop in /root/squid/squid-2.3.STABL

With Regards
Ahsan Khan
Sr. System Admin
Internet Division (OneNet)
Sun Communication Pvt. Ltd.
Pakistan
http://www.one.net.pk
Received on Wed May 31 2000 - 17:06:13 MDT