Can I force gcc not to optimize calling to leaf functions with `-O2' option?

[PRC]

Hi All,
I wonder if I can inform gcc not to optimize calling to leaf functions.

For example
-------------------
void say_hello()
{
	printf("Hello\n");
}
void func()
{
	say_hello();
}


with -O2 option, gcc will optimize 
	jal say_hello
	...
	jr ra
	...
to
	j  say_hello
	
This is not what I want in some case. The start of the function can be located
by searching `addiu sp, XXXX' instruction, and the end of the function by
searching `jr ra', beginning with EPC when expctions arise, if all function calls
have their own exits. By this way, I can trace down the calling frames. But this
optimization breaks the rule and will confused the tracer. And the `-O2' option
is neccessary since some bugs are only exposed on `-O2'.

Is there an approach for this purpose?

Best Regards
PRC
Mar 29, 2008