Re: High-Integrity OO and controlled types

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Wed, 04 May 2011 19:06:55 +0200, Georg Bauhaus wrote:

> On 04.05.11 18:23, Dmitry A. Kazakov wrote:
> 
>>> Try adding pragma Profile (Ravenscar) there ;.)
>> 
>> I don't care much about Ravenscar, which is too limiting for almost
>> anything. There are limitations to make life easier for the readers and
>> ones for the compiler and prover. They are not same, some contradict to the
>> goals of each other. I always choose the former over the latter.
> 
> Does it work when systems need to be fast at the lower levels?

Performance optimization is a different angle. There is no obvious reason
why following or ignoring Ravenscar's restrictions should result in either
faster or slower program.

The problem with Ravenscar is that in my case it unfortunately does not let
me fulfill the functional requirements I have. Under such circumstances
non-functional niceties play no role. I am not sure if the problem is
fundamental, i.e. no conformant program exists. Even if it did I could not
design or understand it anyway...

>>> Is there really little overhead when Restore is replaced
>>> with some objects?
>> 
>> [...]
>> 
>> Negligible since used upon an exception, which I hope is not to propagate
>> at 100ns rate.
> 
> Ah, o.K., I should have said source code maintenance overhead, too,
> and increased system complexity.

Developing /= maintenance.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de