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diff --git a/mtp/tw_sys_atomics.h b/mtp/tw_sys_atomics.h
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+++ b/mtp/tw_sys_atomics.h
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+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#ifndef _TW_SYS_ATOMICS_H
+#define _TW_SYS_ATOMICS_H
+
+#include <sys/cdefs.h>
+#include <sys/time.h>
+
+__BEGIN_DECLS
+
+/* Note: atomic operations that were exported by the C library didn't
+ *       provide any memory barriers, which created potential issues on
+ *       multi-core devices. We now define them as inlined calls to
+ *       GCC sync builtins, which always provide a full barrier.
+ *
+ *       NOTE: The C library still exports atomic functions by the same
+ *              name to ensure ABI stability for existing NDK machine code.
+ *
+ *       If you are an NDK developer, we encourage you to rebuild your
+ *       unmodified sources against this header as soon as possible.
+ */
+
+/* This was kanged from Android 4.4 bionic/libc/include/sys/atomics.h
+ * This header was removed in Android 5.0 in favor of stdatomics.h but
+ * to maintain compatibility across multiple trees, we are including our
+ * own copy.
+ */
+
+#ifndef __ATOMIC_INLINE__
+#define __ATOMIC_INLINE__ static __inline__ __attribute__((always_inline))
+#endif
+
+__ATOMIC_INLINE__ int
+__tw_atomic_cmpxchg(int old_value, int new_value, volatile int* ptr)
+{
+    /* We must return 0 on success */
+    return __sync_val_compare_and_swap(ptr, old_value, new_value) != old_value;
+}
+
+__END_DECLS
+
+#endif /* _TW_SYS_ATOMICS_H */