$ gcc -g -O0 test.c -lexecinfo
$ ./a.out # new libc
^Cx 2
Backtrace 3 stack frames.
0x400bb0 <handler+0x30> at ./a.out
0x7f7ff72a5290 <__sigtramp_siginfo_2> at /usr/lib/libc.so.12
0x400c03 <main+0x1e> at ./a.out

$ ./a.out # old libc
^Cx 2
Backtrace 1 stack frames.
0x400bb0 <handler+0x30> at ./a.out

$ cat test.c
#include <signal.h>
#include <execinfo.h>
#include <stdio.h>
#include <stddef.h>

static void
handler(int s)
{
	printf("x %d\n", s);

	void *array[10];
	size_t size = backtrace (array, 10);
	printf ("Backtrace %zd stack frames.\n", size);
	backtrace_symbols_fd (array, size, 2);
}

int
main(int argc, char **argv)
{
	signal(SIGINT, handler);
	for (;;)
		continue;
	return 0;
}