http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49016
--- Comment #7 from Lee Merrill <merrill_707_1 at yahoo dot com> 2011-05-17 13:42:23 UTC --- I think what is happening in the compiler BTW is that a "sub $XX, %rsp" is dropping out, perhaps as an optimization. If for example, you comment out the "#define inline" line in the test code, a stack adjustment appears: 0: 55 push %rbp 1: 48 89 e5 mov %rsp,%rbp 4: 48 83 ec 10 sub $0x10,%rsp # SP adjustment here 8: 48 89 7d f8 mov %rdi,-0x8(%rbp) c: 89 75 f4 mov %esi,-0xc(%rbp) etc. And as far as using stack space below your stack pointer, suppose someone has an operating system that runs applications at the same privilege level as the OS?
