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From: Stefan Ring <stefanrin@gmail.com>
Date: Tue, 21 Dec 2021 17:05:44 +0100
Message-ID: <CAAxjCEwaUQ8bGd7NYqTjVL=VN4PbRsXx7PvJJWLwd9SL9oZ1RQ@mail.gmail.com>
Subject: Re: broken code only when optimized "-O2"
To: Adrian Moreno <amorenoz@redhat.com>
Cc: gcc-help <gcc-help@gcc.gnu.org>
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On Tue, Dec 21, 2021 at 4:40 PM Adrian Moreno via Gcc-help
<gcc-help@gcc.gnu.org> wrote:
>
> I'd really appreciate any hint or idea to try to understand this problem.

I guess the compiler doesn't like the dereferencing of uninitialized
pointers (in the sizeof expressions). I am not 100% sure that this
counts as dereferencing, but I would assume so. Because of this the
compiler will be free to behave however it likes to.