Socks Server 5

hello, I make ss5-3.7.9-1 in x86_64, it appear follow error, but I make on
i386 platform is ok,how to resolve it,thanks!

make[1]: Entering directory `/root/ss5-3.7.9/common'
gcc -g -O2 -DLINUX -D_FILE_OFFSET_BITS=64 -I . -I ../include -D EPOLL_IO
-c -o SS5OpenLdap.o SS5OpenLdap.c
make[1]: Leaving directory `/root/ss5-3.7.9/common'
make[1]: Entering directory `/root/ss5-3.7.9/modules'
make[2]: Entering directory `/root/ss5-3.7.9/modules/mod_socks4'
gcc -g -O2 -DLINUX -D_FILE_OFFSET_BITS=64 -I . -I ../../include -shared
-fPIC -D EPOLL_IO -c -o SS5Mod_socks4.o SS5Mod_socks4.c
gcc -g -O2 -DLINUX -D_FILE_OFFSET_BITS=64 -I . -I ../../include -shared
-fPIC -D EPOLL_IO -o mod_socks4.so SS5Mod_socks4.o
../../common/SS5OpenLdap.o -lpthread
make[2]: Leaving directory `/root/ss5-3.7.9/modules/mod_socks4'
make[1]: Leaving directory `/root/ss5-3.7.9/modules'