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From: Eric Gallager <egall@gwmail.gwu.edu>
Date: Sun, 21 Aug 2022 19:12:49 -0400
Message-ID: <CAMfHzOuh=wGstsK4u_xxLTGHkDc0BjKmbDY8s=Y+FtwJeAJawg@mail.gmail.com>
Subject: Re: New/improved warning option for padding bytes
To: Jonas Rahlf <jonas.rahlf@gmail.com>
Cc: GCC Development <gcc@gcc.gnu.org>
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On Fri, Aug 19, 2022 at 6:13 AM Jonas Rahlf via Gcc <gcc@gcc.gnu.org> wrote:
>
> As a firmware developer I would appreciate a warning option about padding
> bytes, but only for such cases where you can reduce the number of padding
> bytes by rearranging the fields.
>
> The current -Wpadded warns about all padding bytes, which is annoying.
>
> The concept sounds simple: you rearrange all fields from large to small and
> check if the size changed.
>
> The goal is to more easily optimize RAM/flash in space constrained systems.
>
> Jonas

That sounds like bug 52981: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=52981