A fully abstract compiler prevents security features of the source language from being bypassed by an attacker operating at the target language level. Unfortunately, developing fully abstract compilers is very complex, and it is even more so when the target language is an untyped assembly language. To provide a fully abstract compiler that targets untyped assembly, it has been suggested to extend the target language with a protected module architecture—an assembly-level isolation mechanism which can be found in next-generation processors. This article provides a fully abstract compilation scheme whose source language is an object-oriented, high-level language and whose target language is such an extended assembly language. The source language enjoys features such as dynamic memory allocation and exceptions. Secure compilation of first-order method references, cross-package inheritance, and inner classes is also presented. Moreover, this article contains the formal proof of full abstraction of the compilation scheme. Measurements of the overhead introduced by the compilation scheme indicate that it is negligible.

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We present the extension of previous two-dimensional simulations of the timedependent evolution of non-relativistic outflows from the surface of Keplerian accretion disks, to three dimensions. As in the previous work, we investigate the outflow that arises from a magnetised accretion disk, that is initially in hydrostatic balance with its surrounding cold corona. The accretion disk itself is taken to provide a set of fixed boundary conditions for the problem.

External uniqueness is a surprising new way to add unique references to an OOPL. The idea is that an externally unique reference is the only reference into an aggregate from outside the aggregate. Internal references which do not escape the boundary of the aggregate are innocuous and therefore permitted. Based on ownership types, our proposal not only overcomes an abstraction problem from which existing uniqueness proposals suffer, it also enables many examples which are inherently not unique, such as a unique reference to a set of links in a doubly-linked list, without losing the benefits of uniqueness.