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From: Georg Bauhaus <sb463ba@l1-hrz.uni-duisburg.de>
Newsgroups: comp.lang.ada
Subject: Re: Certified C compilers for safety-critical embedded systems
Date: Thu, 15 Jan 2004 01:12:51 +0000 (UTC)
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Aatu Koskensilta <aatu.koskensilta@xortec.fi> wrote:
:> Can a self-hosting compiler then in theory decide whether it is
:> correct? For the former or the latter languages?
: 
: I don't think I understand your question. Are you asking about a 
: situation in which a compiler is used to compile itself?

The choice of the word "correct" was a bit thoughtless. Sorry.
I was indeed thinking about a compiler and its input when it
happens to be the compiler itself, or a patched version.
If it HALTs, I know nothing about correctness from this fact
(there wouldn't be any compiler bugs, after all).
And after reading yours and Robert Eachus' explanations, I trust
there is no way to mechanically decide whether a "real world" compiler
works correctly as described in a consistent standard, even for
the finite amount of input programs that capacity limits
will allow. Is this halfway correct?


thanks,
-- Georg