Re: Ada is almost useless in embedded systems

[john@assen.demon.co.uk (John McCabe)]

dewar@cs.nyu.edu (Robert Dewar) wrote:

>John McCabe says

<snip>

>It might be easy to use, but it obviously has nothing to do with
>package Machine_Code, which uses aggregates rather than procedure
>calls. What you describe is more closely related to the approach
>described in th Ada 95 RM as "intrinsic subprograms"

Yes, I've read about them.

>If the compiler you cite calls their package Machine_Code, then it clearly
>is not an accurate Ada 83 implementation, rather it is an impermissible
>extension.

If you remember some of my previous postings etc about my current Ada
compiler, I think you could probably reach the conclusion that _I_
don't think it is an accurate Ada 83 implementation (motive - be wary
of TLD!). It makes me wonder why there is such a fuss about
validation! I know the validation suite is limited in what is actually
checked but this seems a bit outrageous.

>However, in Ada 95, either approach is allowed (package Machine_Code or
<snip>

That does sound better to me (as far as the language is concerned),
but obviously TLD appear to be being a bit strange in their
interpretation here!

>For another example of this, look at the support for machine intrinsics
>in the Alsys x86 technology (that's my design, so I know it well :-)
<snip>

I don't think I'll bother looking for the moment thank you (at least
not until I need to use an x86 compiler) but that approach sounds
similar to the MSPs (Machine Specific Procedures) package that comes
with PSS's compiler. Do you know of it?

>By the way, the plan for GNAT in this area is to define some additional
>attributes which hook into the existing GCC mechanism for assembly
>language inserts (see description in GNU C manual).

Presumably this is related to the C compilers asm("string") call?


Best Regards
John McCabe <john@assen.demon.co.uk>