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From: Florian Weimer <fweimer@redhat.com>
To: James Hanley <jhanley@dgtlrift.com>
Cc: libc-alpha@sourceware.org
Subject: Re: in6_addr struct union with uint64_t
References: <CAF++6APe8VxPaSwuToFeAfugvXOY=pb19Td-e4r4_1O4b1Ja5Q@mail.gmail.com>
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	<CAF++6APqTNuLgB8XkH8bHboAjqqoogY4h=h+ohXh-agaQaVQZA@mail.gmail.com>
Date: Mon, 29 Jan 2024 20:08:23 +0100
In-Reply-To: <CAF++6APqTNuLgB8XkH8bHboAjqqoogY4h=h+ohXh-agaQaVQZA@mail.gmail.com>
	(James Hanley's message of "Mon, 29 Jan 2024 13:02:11 -0500")
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* James Hanley:

> I believe I understand your point - is the concern that the alignment
> issue would be manifested with an already compiled legacy application
> utilizing this newly built library and would require the in6_addr to
> be 16-byte aligned or hit a runtime exception if the address passed in
> isn't aligned - correct?

It's not so much the run-time exception/trap, but that struct offsets
may change as a result of the increased alignment.

If the compiler supports decreasing alignment, we could add the
additional arrays, but I'm not sure if that's worth it.

Thanks,
Florian