after using __KERNEL__, 'u8' can be found, but it occurred other errors:

gcc -DCONFIG_X86_32 -D__KERNEL__ -I/usr/src/linux-headers-2.6.28-11/include -I/usr/src/linux-headers-2.6.28-11/arch/x86/include -O0 -g3 -Wall -c -fmessage-length=0 -MMD -MP -MF"src/test_atomic.d" -MT"src/test_atomic.d" -o"src/test_atomic.o" "../src/test_atomic.c"

/usr/src/linux-headers-2.6.28-11/include/linux/log2.h:52: 错误： expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘is_power_of_2’
In file included from /usr/src/linux-headers-2.6.28-11/arch/x86/include/asm/system.h:10,
from /usr/src/linux-headers-2.6.28-11/arch/x86/include/asm/processor.h:17,
from /usr/src/linux-headers-2.6.28-11/arch/x86/include/asm/atomic_32.h:5,
from /usr/src/linux-headers-2.6.28-11/arch/x86/include/asm/atomic.h:2,
from ../src/test_atomic.c:14:
/usr/src/linux-headers-2.6.28-11/include/linux/kernel.h:236: 错误： expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘printk_timed_ratelimit’
/usr/src/linux-headers-2.6.28-11/include/linux/kernel.h:303: 错误： expected declaration specifiers or ‘...’ before ‘bool’
/usr/src/linux-headers-2.6.28-11/include/linux

I can't compile atomic.h in Ubuntu 9.4, below is source code:

#include <stdio.h>
#include <stdlib.h>

#include <asm/atomic.h>

int main(void) {
puts("!!!Hello World!!!");
return EXIT_SUCCESS;
}

the following is the error info:
/usr/src/linux-headers-2.6.28-11/arch/x86/include/asm/alternative.h:45: 错误： expected specifier-qualifier-list before ‘u8'

Can anyone help me?