[vbox-dev] [linux guest on linux host] alarm() system call broken?

[walt]

(vbox 4.2.4_gentoo_r81684)

The code snippet below is part of a 'configure' script that compiles okay but hangs forever when it runs on a linux guest.  I'm wondering if it's a vbox bug or a gentoo bug (i.e. my host and guest machines).  Can anyone reproduce?  Thanks.

#include <errno.h>
#include <unistd.h>
#include <signal.h>
static void
handle_alarm (int sig)
{
  if (sig != SIGALRM)
    _exit (2);
}

int
main ()
{

    /* Failure to compile this test due to missing alarm is okay,
       since all such platforms (mingw) also lack sleep.  */
    unsigned int pentecost = 50 * 24 * 60 * 60; /* 50 days.  */
    unsigned int remaining;
    signal (SIGALRM, handle_alarm);
    alarm (1);
    remaining = sleep (pentecost);
    if (remaining > pentecost)
      return 3;
    if (remaining <= pentecost - 10)
      return 4;
    return 0;

  ;
  return 0;
}