#include <setjmp.h>
#include <stdio.h>
#include <time.h>
jmp_buf j;
void do_jump(void)
{
// We can't let the compiler know this will always happen or it might make
// optimizations that break our test.
if (!clock())
longjmp(j, 1); // non-local goto
}
int main (void)
{
if (setjmp(j) == 0)
do_jump();
else
return 0; // destination of longjmp
return 1;
}