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From: Victor Porton <porton@narod.ru>
Newsgroups: comp.lang.ada
Subject: Re: Unchecked_Union record inside an other record - trouble
Date: Fri, 08 Aug 2014 23:01:30 +0300
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Date: 2014-08-08T23:01:30+03:00
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Per Sandberg wrote:

> You shall not try to write interface code by hand you shall use the
> compiler
> gcc -c -fdump-ada-spec <more arguments and files>
> see GNAT Users guide.
> 
> Since humans makes a heap load of errors and erronous asumptions when
> they try to translate the contents of a .h file to an .ads file, the
> compiler does a much better job.

I considered this approach but refused to use auto-generated code.

One reason is that it uses a system address type where it should be access 
arguments to a function. In my opinion, this is not guaranteed to work by 
ARM.

The other reason is that I can fine tune types. One especially useful usage 
pattern is that I sometimes pass char_array and sometimes chars_ptr to a 
function which requires a char or a void pointer. Also I can differentiate 
"access" arguments and pass-by-value, what is a sometimes useful 
distinction.

This use case simplifies my coding probably more that the necessity to write 
imported C functions manually.

And last it does not take really much time to code imported C functions 
manually. I may make errors here, but as for now I've instead found a few 
errors in the C library with which I am trying to interface.

-- 
Victor Porton - http://portonvictor.org