CHECK_CXX_SOURCE_RUNS ( "
#include <signal.h>
#include <string.h>
#include <sys/time.h>
void ReportProfileSample(int, siginfo_t *, void *) { }
int main() {
    struct sigaction sa;
    memset(&sa, 0, sizeof(sa));
    sa.sa_sigaction = ReportProfileSample;
    sa.sa_flags = SA_RESTART | SA_SIGINFO;
    sigemptyset(&sa.sa_mask);
    sigaction(SIGPROF, &sa, NULL);
    static struct itimerval timer;
    return setitimer(ITIMER_PROF, &timer, NULL) == 0 ? 0 : 1;
}
" HAVE_ITIMER )