#include <locale.h>
#include <regex.h>

static char const combining_acute_accent[] = "\xcc\x81";

int
main (void)
{
  regex_t re;
  if (! setlocale (LC_ALL, "en_US.UTF-8"))
    return 3;
  if (regcomp (&re, "[[:alpha:]]", 0) != 0)
    return 2;
  if (regexec (&re, combining_acute_accent, 0, 0, 0) != 0)
    return 1;
  return 0;
}