Call _exit() not exit() from abort() if we are unable to kill ourselves

to avoid flushing stdio twice.  This code path should never really
happen though.  Also make the function declaration ANSI.  OK deraadt@

src/lib/libc/stdlib/abort.c

@@ -28,7 +28,7 @@
  */
 
 #if defined(LIBC_SCCS) && !defined(lint)
-static char *rcsid = "$OpenBSD: abort.c,v 1.12 2003/06/02 20:18:37 millert Exp $";
+static char *rcsid = "$OpenBSD: abort.c,v 1.13 2004/01/20 19:35:17 millert Exp $";
 #endif /* LIBC_SCCS and not lint */
 
 #include <signal.h>
@@ -38,7 +38,7 @@ static char *rcsid = "$OpenBSD: abort.c,v 1.12 2003/06/02 20:18:37 millert Exp $
 #include "atexit.h"
 
 void
-abort()
+abort(void)
 {
 	struct atexit *p = __atexit;
 	static int cleanup_called = 0;
@@ -74,5 +74,5 @@ abort()
 	(void)signal(SIGABRT, SIG_DFL);
 	(void)_thread_sys_sigprocmask(SIG_SETMASK, &mask, (sigset_t *)NULL);
 	(void)kill(getpid(), SIGABRT);
-	exit(1);
+	_exit(1);
 }