Android doesn't have posix_memalign(), so use memalign()

src/shared/platform/posix/aligned_malloc.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 "native_client/src/shared/platform/aligned_malloc.h"
 
 #include <stdlib.h>
 
 
 void *NaClAlignedMalloc(size_t size, size_t alignment) {
+  /*
+   * Bionic in Android ICS (4.0) and earlier doesn't have
+   * posix_memalign(), so we shall use memalign(), which
+   * luckily returns free()'able memory.

[Mark Seaborn, 2012/11/06 13:54:44]

How about: "luckily, in Bionic, returns free()'able memory, although it is not
required to in general."

+   * TODO(olonho): once/if we'll obsolete 4.0 support remove this
+   * #ifdef.
+   */
+#if NACL_ANDROID
+  return memalign(alignment, size);
+#else
   void *block;
   if (posix_memalign(&block, alignment, size) != 0)
     return NULL;
   return block;
+#endif
 }
 
 void NaClAlignedFree(void *block) {
   free(block);
 }