> -O3 is known to be buggy and dangerous. You shouldn't use it.

Looks like -O2 -mpentium is enough.

enami.

#include <sys/types.h>

#include <machine/intr.h>

extern /* __volatile */ int piyo;
void
hoge()
{
	int s;

	s = splbio();
	piyo++;
	splx(s);
}