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From: Eric Botcazou <ebotcazou@libertysurf.fr>
To: Martin Uecker <ma.uecker@gmail.com>
Cc: Richard Biener <richard.guenther@gmail.com>,
 "gcc@gcc.gnu.org" <gcc@gcc.gnu.org>
Subject: Re: reordering of trapping operations and volatile
Date: Sat, 08 Jan 2022 18:33:57 +0100
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> Most C programmers would assume that volatile accesses already
> provides this guarantee, so actually doing so would be good.

I'm a little skeptical of this statement: if it was true, how come the most 
recent version of the standard does not provide it 30 years after the language 
was first standardized?

> Or a more practical example: While debugging some embedded
> device, it would also be very annoying if the compilers reorders
> some trap before some debugging output. I could easily imagine
> loosing hours figuring out what happens.

The thing to do to avoid losing these hours is to debug the code at -O0.

-- 
Eric Botcazou