win: Add an explicit intrin.h include to work around a clang-cl bug.

src/shared/platform/win/nacl_secure_random.c

 /*
  * Copyright (c) 2008 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 Service Runtime.  Secure RNG implementation.
  */
 #include <windows.h>
 
+/* Work around a clang-cl bug: SecureZeroMemory() below uses __stosb() but
+ * windows.h only declares that intrinsic and then uses `#pragma intrinsic` for
+ * it.  clang-cl doesn't implement `#pragma intrinsic` yet; it instead defines
+ * the function as an always-inline symbol in its intrin.h.
+ * TODO(thakis): Remove this once http://llvm.org/PR19898 is fixed.
+ */
+#include <intrin.h>
+
 /*
  * #define needed to link in RtlGenRandom(), a.k.a. SystemFunction036. See
  * the "Community Additions" comment on MSDN here:
  *   http://msdn.microsoft.com/en-us/library/windows/desktop/aa387694.aspx
  */
 #define SystemFunction036 NTAPI SystemFunction036
 #include <NTSecAPI.h>
 #undef SystemFunction036
 
 #include "native_client/src/shared/platform/nacl_log.h"
@@ skipping 54 matching lines @@
   if (0 > self->nvalid) {
     NaClLog(LOG_FATAL,
             "NaClSecureRngGenByte: illegal buffer state, nvalid = %d\n",
             self->nvalid);
   }
   if (0 == self->nvalid) {
     NaClSecureRngFilbuf(self);
   }
   return self->buf[--self->nvalid];
 }