Re: Default rep specs for record types - documented??

[Stephen Leake <stephen_leake@acm.org>]

Anonymous Coward <bogus_addy@bogus_domain.net> writes:

>>> I'm not looking forward to rep specing records bit for bit simply to
>>> enforce the same order of elements that's specified in the operation
>>> specs.
>> 
>> If 'operation specs' are defining the hardware you are interfacing
>> to, then yes, you need a rep clause for each hardware register. The
>> time spent writing those clauses _will_ be repaid later when it
>> comes to testing on the hardware; there _will_ be fewer bugs.
>
> Perhaps, but for interfacing with C operations (which is my case), I
> would prefer to simply write "pragma convention (C, my_record)" and be
> able to expect the compiler to base the representational spec purely
> off the operational spec, just as the C compiler would for a structure
> that only has an operational spec.  

If by 'C', your Ada compiler means your C compiler, this will work. 

> I should not have to micromanage the bitwise layout of a record to
> interface with C code.  It puts me at a lower level, and positions me
> to make human errors (like writing an incomplete rep spec for a
> record), when such errors can be avoided by keeping it high level.

Which is why 'convention (C)' is available. 

> <snip>  Or maybe better yet, mandate
> that pragma convention (C,...) matches representation order to
> declaration order to keep the number of pragmas minimal.

Hmm. You seem to be saying "convention (C) doesn't work for me". That
seems like a bug. Can you post some code that doesn't work? Or have
you submitted a bug report?

-- 
-- Stephe