#include <assert.h>
    #include <stdio.h>
    #include <stdlib.h>
    #include <signal.h>
    #include <limits.h>
 
    void segfault_handler(int sig);
 
    int counter = 0;
 
    int main(void) {
        int *fubar = malloc(0);
 
        assert(signal(SIGSEGV, segfault_handler) != SIG_ERR);
        assert(signal(SIGILL, segfault_handler) != SIG_ERR);
        assert(signal(SIGFPE, segfault_handler) != SIG_ERR);
 
        for (;;) {
            printf("Assigning to fubar[%d]\n", counter);
            fubar[counter] = INT_MIN;
            counter = counter * 2 + 1;
        }
    }
 
    void segfault_handler(int sig) {
        /* NOTE: Using printf inside a signal handler is also undefined behaviour */
        printf("Fault when counter is %d\n", counter);
        exit(EXIT_FAILURE);
    }
 

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