Bus error.

[CyberPsychotic]

Hello people,
 I've got the feeling like I've missed something:
 so far I understood two actions:

gcc foo.c -o foo
 and 
gcc -S foo.c
gcc foo.s -o foo
 
should produce similar (well almost) code. However, when in latter case I
run foo, I get Bus error(core dumped) message. Ideas what goes wrong here?
I think that's something to do with alignment,  but not sure.

Thanks beforehands
 Fyodor