Defects and Faults in Algorithms, Programs and Instruction Sequences

Abstract

A new definition of algorithms is given, where algorithms are understood as cognitive 'entities', the definition of which is done in tandem with so-called algorhymes, which are entities serving as documentation of algorithms. Based on this definition the notions of fault and defect are reconsidered in relation to instruction sequences, programs and algorithms. Programs as well as algorithms are considered capable of containing moral defects, the notion of a moral defect is developed in some detail. The notion of a moral fault is considered implausible.

Four Notions of Fault for Program Specifications

“…As it turns out, however, unlike with the case of program faults we were unable to find any existing work on specification faults, apart from the idea that if a specification has no implementation something must be wrong. In [7] the notion of an algorithm fault is defined, a definition which is indirectly based on the notion of a program fault.…”

Accusations in the context of computer programming

“…• not having used a systematic and known process for requirements capture so that A finds it hard to grasp the completeness of the result, • not having grasped the (and cost) of prototyping for parts of the requirements capture process, • having changed the interpretation of certain fragments in R req with respect to the interpretation which was assumed in previous stages of the process, • implicitly demanding that A produces advice concerning requirements capture without making that demand explicit and without providing adequate compensation for it, • Not allowing A (by way of limited project funding) to achieve a formal specification of the behaviour of the program to be produced, • Requiring that A will design X as the implementation of an algorithm P (that supposedly is compliant with R req ) and which B has transferred to A in the form of a flock of algorhymes (see [8] for this notion); (now A may accuse B of) having provided a faulty algorithm (see [8]).…”

“…• C accuses A of having used (copyright infringement, including misuse of open source code) an IPR protected program (with IPR/copyright belonging to C) in the construction of X, • B accuses A of it having become vulnerable to third party IPR based claims because of copyright and/or patent infringement(s) in connection to X which become vulnerabilities relevant for B upon adoption and use of X by B, • C accuses A of having used (patent infringement) an IPR protected algorhyme (see [8]) (with IPR/software patent/algorithm patent belonging to C) in the construction of X, • B accuses A of having delivered X including a moral defect (see [8] for that notion).…”

“…In what follows, a program will be understood as a digital entity which qualifies as a program according to the definition of (computer) programs given in [8]. In brief the definition states that a program is an entity which obtains its meaning by way of a translation to a repeating single pass instruction sequence in the program algebra notation of [12,14] and [13].…”

“…• having asked A to develop an implementation of R req wile doing so unavoidably leads to a program with a moral flaw (see [8]),…”