Open System Portability Checker Update (Mar 93)

New ports

OSPC has now been ported to the Digital Alpha AXP RISC chip running OSF/1.

OSPC running under OSF/1 on Alpha AXP provides the same functionality as supplied on all supported platforms. The Digital C compiler proved to be well documented and very close to the ANSI C standard (this compiler was validated in the New Year by NIST as being ANSI conforming). OSF/1 is a rewrite of Unix based on the Mach kernel from Carnege Mellon University. As such there are a number of differences and extensions when compared against BSD or the SVID. From our point of view one of the advantages of porting to a new platform is that we get to extract a great deal of information on that platform. The Alpha AXP was no exception and over a quarter of a megabyte of profile information was obtained.

OSPC has also been reported to HP9000 series 700 (PA-RISC) running HP/UX. This port provided us with the opportunity to update the platform profile information for this system.

64/32 bit architecture

The Alpha Risc chip from Digital is the first of many that uses a 64 bit architecture. The main problems associated with porting to this `enlarged' cpu are caused by the breaking of an assumption implicit in many applications. On previous chips the sizes of int, long and pointers were the same (32 bits). In a 64 bit environment int's usually occupy 32 bits with the other two datatypes occupying 64 bits. Code that relies of default promotions (that will invariably involve int type) will no longer work correctly.

Another problem caused by the larger number of bits is that the types of some literals change. Those that used to have type unsigned int or unsigned long can now fit in a signed quantity. Thus in some cases expressions that used to have an unsigned type now have signed type.

OSPC is now built to be able to handle integral types up to 64 bits. It is can also flag those situations where a change of size of scalar type can affect software portability.

Pioneer Technology

Pioneer Technology are a company working in the high integrety arena. Through past involvement with Knowledge Software it was agreed that Pioneer would be an ideal sales agent for OSPC. To this end an agreement was signed in August of last year.

David Munro is spearheading the sales and marketing side for Pioneer. He can be reached on (0252) 79

Consultancy

Some companies have expressed a desire to have an independent third party check there code, rather than purchasing a copy of OSPC. So Knowledge Software are now offering a consulting service. Pricing is based on three daily rates, one for the first day, another for the second and third days and thereafter a standard daily rate.

Applications are checked using OSPC. The developer gets to keep the log files and receives a report on the standards conformance of their code. There is also plenty of opportunity to discuss the implications of the warnings being generated and what might be done to remove them.

For more information contact Knowledge Software on (0252) 520667.

New standards supported

The OSPC platform profile database continues to grow with the addition of support for XPG/4, X.400 and the draft international standard for POSIX.2 (shell and utilities).

The documentation for XPG/4 is much improved on that provided for XPG/3. It is hoped that this improvement will reduce the number of queries we receive on what exactly XPG says. As is to be expected of an industry standards body on the leading edge some of the facilities described are now out of date. In particular the multi-byte support extensions for C have moved on considerably (WG14 have just published their first Committee Draft describing this functionality).



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