Explicitly enable the use of init/fini array under PNaCl

newlib/libc/misc/fini.c

 /*
  * Copyright (C) 2010 CodeSourcery, Inc.
  *
  * Permission to use, copy, modify, and distribute this file
  * for any purpose is hereby granted without fee, provided that
  * the above copyright notice and this notice appears in all
  * copies.
  *
  * This file is distributed WITHOUT ANY WARRANTY; without even the implied
  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  */
 
 /* Handle ELF .{pre_init,init,fini}_array sections.  */
 #include <sys/types.h>
 
-#ifdef HAVE_INITFINI_ARRAY
+#if defined(HAVE_INITFINI_ARRAY) || defined(__pnacl__)
 extern void (*__fini_array_start []) (void) __attribute__((weak));
 extern void (*__fini_array_end []) (void) __attribute__((weak));
 
 extern void _fini (void);
 
 /* Run all the cleanup routines.  */
 void
 __libc_fini_array (void)
 {
   size_t count;
   size_t i;
   
   count = __fini_array_end - __fini_array_start;
   for (i = count; i > 0; i--)
     __fini_array_start[i-1] ();
 
   _fini ();
 }
 #endif