backtrace() falls on memcpy exception

I managed to break backtrace(). I so happend that I can’t trace some program crashes like so:

void backtrace_init() {
     struct sigaction sigact;

     sigact.sa_sigaction = crit_err_hdlr;
     sigact.sa_flags = SA_RESTART | SA_SIGINFO;
     sigaction(SIGSEGV, &sigact, (struct sigaction *)NULL);
}

void breakMe() {
     uint8_t * buffer1 = new uint8_t[1024];
     uint8_t * buffer2 = new uint8_t[1024];

     memcpy(buffer1, buffer2, -1); // code breaks and crit_err_hdlr() called
}

void main() {
     backtrace_init();
     breakMe();
}


void crit_err_hdlr(int sig_num, siginfo_t * info, void * ucontext)
{
    enum {
        ARRAY_SIZE = 10,
    };
    void *             array[ARRAY_SIZE];
    size = backtrace(array, ARRAY_SIZE);  // code breaks second time
...
}

Second crash looks like because of malloc() call:
"malloc(): invalid size (unsorted)"

and I can’t save my program crash to log file. How can I make backetrace() call secure?

I tried to backtrace() other bugs like write to nullptr and it works with no problems. backtrace() worked fine, I get call stack array and write it to log file. But with memcpy() crash it fail.

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