Often these kind of errors appear either when some of your preprocessor macros
accidently clashed with the ones from system headers ... or when there's
something seriously wrong with your system.
So before trying anything else, I recommend you to:
a) reboot [nice that we have an OS where we have to explicitly tell that ;) ]
b) run fsck on all your partitions (i.e.: "e2fsck -c" for ext2/3 partitions)
If that didn't help, try to compile your code on another machine. And if that
didn't help either, come back and post your code!
CU
Christian