[Info-vax] VMS and the embedded world, was: Re: PowerX Roadmap - Extended beyond 2020

[David Froble]

clairgrant71 at gmail.com wrote:

> This was all true years ago but after porting to Alpha and especially to
> Itanium, architecture-specific knowledge is in very few places and extremely
> little of the OS is aware of architecture and that is centralized. At this
> point it is not so much the design of VMS that makes it time consuming to
> port, it is the fact that it was written in VAX assembler and BLISS and uses
> the GEM code generator. (Yes, we have explored converting to C three times
> and rejected that approach each time).

Since you really needed, at a minimum, the Macro-32 compiler, continuing to use 
the Macro-32 code is the correct decision.  Re-writing it would be needless 
work.  Re-writing it would introduce bugs, and such.

Some VMS customers have Macro-32 code, and without the compiler would no longer 
be able to run on VMS without re-writing their applications, with the same 
problems mentioned above.

To possibly a lesser extent, the same reasons apply to Bliss.