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From: Martin Dowie <martin.dowie@btopenworld.com>
Newsgroups: comp.lang.ada
Subject: Re: private types
Date: Sat, 18 Mar 2006 12:06:37 +0000 (UTC)
Organization: BT Openworld
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Date: 2006-03-18T12:06:37+00:00
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Randy Brukardt wrote:
> It's not just testing. Ada 95 is very clear that an Ada compiler cannot
> assume an object is in range unless it can prove it is initialized. Explicit
> initialization makes this proof trivial (and leaving it out may make it
> impossible to prove.) Thus, given
>     A : Positive := 10;
>     B : Positive;
> the compiler can assume that A is in range, potentially being able to
> eliminate checks and speeding up the code. But it cannot assume that B is in
> range (unless it can prove that it is initialized further on).
> 
> So I recommend initalizing everything (or assigning it immediately after the
> begin) that could be significant to performance.


Or use a tool like PolySpace, which is very good at spotting this sort 
of thing. (www.polyspace.com).

Cheers

-- Martin