In this paper, we analyse the exception handling mechanism of a state-of-the-art industrial embedded software system. Like many systems implemented in classic programming languages, our subject system uses the popular return-code idiom for dealing with exceptions. Our goal is to evaluate the fault-proneness of this idiom, and we therefore present a characterisation of the idiom, a fault model accompanied by an analysis tool, and empirical data. Our findings show that the idiom is indeed fault prone, but that a simple solution can lead to significant improvements. 1.

this article differentiate the exception-handling needs of CB-RTS as compared to other software paradigms and can serve as a driving force for future research into exception-handling technology.

To compete with optimized C, object-oriented languages need classical optimizations as well as specific object-oriented optimizations. Therefore, a compiler infrastructure that enables object-oriented compiler research isof great interest for the research community. The SUIF compiler system with the OSUIF extension offers such a research environment. SUIF defines an intermediate representation for procedural languages and offers standard optimization passes. OSUIF extends SUIF with an intermediate representation tailored towards object-oriented languages, hence allowing specific object-oriented optimizations. To enable Java-related compiler research in (O)SUIF, we have implemented j2s, a Java bytecode front end for the OSUIF/SUIF 2.0 compiler system. Our compiler uses off-line compilation, so that the whole program is known at compile time. Thus, static whole-program optimizations such as class hierarchy analysis and type inference can be implemented with (O)SUIF and applied during the compilation. j2s supports the complete Java Virtual Machine specification, except for threads and exception handling, which are currently not supported by the runtime system and (O)SUIF. Because we implemented an off-line compiler, the dynamic loading of classes is also not supported. The compiler is divided into the (O)SUIF front end and the runtime system. The main part of

This paper presents a general model for dealing with abnormal events during program execution and describes how this model is implemented in the System. (The System is a library of C definitions that provide light-weight concurrency on uniprocessor and multiprocessor computers running the UNIX operating system. ) Two different techniques can be used to deal with an abnormal event: an exception, which results in an exceptional change in control flow from the point of the abnormal event; and an intervention, which is a routine call from the point of the abnormal event that performs some corrective action. Users can define named exceptions and interventions in conjunction with ones defined by the System. Exception handlers and intervention routines for dealing with abnormal events can be defined/installed at any point in a program. An exception or intervention can then be raised or called, passing data about the abnormal event and returning results for interventions. Interventions can also be activated in other tasks, like a UNIX signal. Such asynchronous interventions may interrupt a task's execution and invoke the specified intervention routine. Asynchronous interventions are found to be useful to get another task's attention when it is not listening through the synchronous mechanism

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