Create a build_config header file.

src/trusted/service_runtime/arch/x86_32/sel_rt_32.c

 /*
  * 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.
  */
 
 #include <float.h>
+#include "native_client/src/include/build_config.h"
 
 #if NACL_WINDOWS
 /*
  * This header declares the _mm_getcsr function.
  */
 #include <mmintrin.h>
 #endif
 
 #include "native_client/src/shared/platform/nacl_log.h"
 #include "native_client/src/trusted/service_runtime/nacl_app_thread.h"
@@ skipping 130 matching lines @@
 }
 
 
 void NaClSignalContextUnsetClobberedRegisters(
     struct NaClSignalContext *sig_ctx) {
   sig_ctx->eax       = 0;
   sig_ctx->ecx       = 0;
   sig_ctx->edx       = 0;
   sig_ctx->flags     = 0;
 }