64位系统下 FD_SET编译问题。不知道咋办了 谢谢

lijuwen

环境： centos6.4 64bit    oracle11r2 64bit   
用cc编译
在.c程序中用64位编译FD_ST FD_CLR等宏报错。32位下无问题

编译如下
cc -g -m64 -c -I/home/ucapdev/app_control/public/include    -c -o pcsp_a_l_called.o pcsp_a_l_called.c
错误如下
pcsp_a_l_called.c: Assembler messages:
pcsp_a_l_called.c:137: Error: Incorrect register `%rdx' used with `l' suffix
pcsp_a_l_called.c:172: Error: Incorrect register `%rax' used with `l' suffix
pcsp_a_l_called.c:232: Error: Incorrect register `%rdx' used with `l' suffix
pcsp_a_l_called.c:250: Error: Incorrect register `%rax' used with `l' suffix
pcsp_a_l_called.c:278: Error: Incorrect register `%rdx' used with `l' suffix
pcsp_a_l_called.c:315: Error: Incorrect register `%rdx' used with `l' suffix

32位 下 没有问题 。请问如何解决。网上找了一堆没有结果。愁啊。这里先谢过了