Create a build_config header file.

src/shared/imc/posix/nacl_imc_posix.cc

 /*
  * Copyright (c) 2012 The Native Client Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 /*
  * NaCl inter-module communication primitives.
  *
  * This file implements common parts of IMC for "UNIX like systems" (i.e. not
  * used on Windows).
  */
 
 #include <assert.h>
 #include <ctype.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <limits.h>
 #include <stdio.h>
 #include <unistd.h>
 #include <sys/mman.h>
 #include <sys/types.h>
+#include "native_client/src/include/nacl_defines.h"
 #if NACL_ANDROID
 #include <linux/ashmem.h>
 #endif
 
 #include <algorithm>
 
 #include "native_client/src/include/atomic_ops.h"
 
 #include "native_client/src/shared/imc/nacl_imc_c.h"
 #include "native_client/src/shared/platform/nacl_check.h"
@@ skipping 163 matching lines @@
   }
   if (flags & NACL_MAP_FIXED) {
     adjusted |= MAP_FIXED;
   }
   return mmap(start, length, kPosixProt[prot & 7], adjusted, memory, offset);
 }
 
 int NaClUnmap(void* start, size_t length) {
   return munmap(start, length);
 }