Although standard tools have been used for lexical and syntactic analysis since the late 1970's, no standard tools exist for the remaining parts of a compiler. Part of the reason for this deficiency is due to the difficulty of producing elegant tools capable of handling the large amount of variation involved in the compiling process. The Object-oriented Compiler Support toolkit is a suite of reusable software components designed to assist the compiler writer with symbol management, type checking, intermediate representation construction, optimization, and code generation. A collection of C++ classes defines a common interface to these tools. Variations in implementation are encapsulated in separately compiled modules that are selected and linked into the resulting compiler. 1 Introduction A compiler is a program that translates a source language into an equivalent target language. The process of compilation is well studied [ASU86, FL91, Hol90, Pys88]. Standard tools have been in use s...

The Walnut kernel is a capability-based operating system kernel that was developed in the Department of Computer Science at Monash University during the 1990s. This kernel is heir to many of the ideas that were implemented in the Password- Capability System. Focusing on the programmer’s view, this paper describes the password-capability model and the features of the Walnut kernel and the design decisions taken in creating it. An ANSI compliant standard I/O library is used as an example of the expressive power of the system. Keywords: Operating Systems, Password-Capabilities 1.