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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: gcc failure (optimised/non-optimised)
Date: Mon, 24 Apr 2017 08:37:09 -0700
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James Harris <james.harris.1@gmail.com> writes:
[...]
> My view is similar to yours but not identical. I accept that a compiler 
> can achieve greater speed by making certain assumptions. What I would 
> want, though, is the compiler at least to say that it was doing 
> something which /could/ alter the behaviour.

The problem is that, as I understand it, it's impractical to do that.

I read an article a while ago from the authors of clang and/or llvm
discussing the issue.  I'll post a link when/if I find it again.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"