#include <stdio.h>
#include <signal.h> /* SIGHUP, SIGINT, SIGKILL */
#include <setjmp.h> /* longjmp, setjmp */

static jmp_buf env;
static int ill = 0;
static void SigHandler(int);

int main(void)
{
    void (*pf_sigill) (int) = signal(SIGILL, SigHandler);
    if(setjmp(env) == 0)
        asm volatile ("mtspr 256, %0\n\t"
                      "vand %%v0, %%v0, %%v0"
                      : : "r" (-1));
    printf("AltiVec %s supported\n", ill ? "is not" : "is");
    signal(SIGILL, pf_sigill);
    return 0;
}

static void SigHandler(int i_signal)
{
    /* Acknowledge the signal received */
    ill = 1;
    sigrelse(i_signal);
    longjmp(env, 1);
}