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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.ada
Subject: Re: How to get Ada to ?cross the chasm??
Date: Fri, 11 May 2018 10:39:23 -0700
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Xref: reader02.eternal-september.org comp.lang.ada:52279
Date: 2018-05-11T10:39:23-07:00
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"Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org> writes:
> Correct C is usually slower than correct Ada that does the same thing,
> because an Ada compiler can optimize away many checks that will be
> left in the C because it's too much effort to manually prove that they
> will never fail.

Going by the Alioth shootout and by the Unzip-Ada program discussed here
recently, Ada = 1.3x slower sounds about right to me.  I'd consider that
to be part of the price (and worth paying) for Ada to leave checks *in*
that the C compiler would unsafely omit.  I don't think the Ada compiler
can prove that much safety by itself (maybe a little bit involving
aliases) that a C compiler can't.  SPARK is a different story, but that
ramps up the development effort to a new level.