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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/106873] unsigned short skips byte when used for memory
 mapping depending on position in structure
Date: Wed, 07 Sep 2022 16:45:01 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D106873

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Kemal Akcam from comment #3)
> I did not report as if unsigned short was different than 2 bytes.
>=20
> Please check the output and explain=20
> 1. why output values changes?
> 2. why it reads/advances 10 bytes instead of 8 bytes?

Again you misunderstand everything. The ABI has a requirement for alignment=
 of
some fields and that is what is called padding.
This is why I said you get a warning with -Wpadding .
If you want to remove this padding, you either use a bitfield or you use the
attribute packed.=