This package contains code that relies on sun.misc.Unsafe. Before using it you MUST assert UnsafeAccess.isUnsafeAvailable() == true

Much of the code in this package comes from or is inspired by the JCTools project: https://github.com/JCTools/JCTools

JCTools has now published artifacts (https://github.com/JCTools/JCTools/issues/17) so RxJava could add JCTools as a "shadow" dependency (https://github.com/ReactiveX/RxJava/issues/1735). 
RxJava has a "zero dependency" policy for the core library, so if we do add it as a dependency, it won't be an externally visible dependency that results in a separate jar.

The license for the JCTools code is https://github.com/JCTools/JCTools/blob/master/LICENSE

As of June 10 2014 when this code was copied the LICENSE read as:

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