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Date: Mon, 5 May 2008 11:32:29 -0700
From: "Carl Shapiro" <carl.shapiro@gmail.com>
To: "Kris Kennaway" <kris@freebsd.org>
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References: <4dcb5abd0805050540m292b319aw52aa2cb8ba018e12@mail.gmail.com>
	<481F0DB3.9070505@FreeBSD.org> <481F48EE.3050806@elischer.org>
	<481F4EED.2030300@FreeBSD.org>
Cc: freebsd-hackers@freebsd.org, Julian Elischer <julian@elischer.org>
Subject: Re: binary compatibility query
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Kris & Julian

Thank you for clarifiying the compatibility situation.  This
information was exactly what I was looking for.

I have a follow-up question based on this remark...

On 5/5/08, Kris Kennaway <kris@freebsd.org> wrote:
>  Actually we don't attempt to keep this form of ABI compatibility (running
> 6.3 binaries on 6.0, for example), because it basically precludes ever
> adding new functions to libc within a branch, or new syscalls to the kernel.
>  You are correct that often binaries will not notice these accumulated
> changes though, or can be carefully constructed to avoid them.

If my binary only executes system calls indirectly through libc
interfaces, as far as libc and libm are concerned, are new symbols the
only thing I need to worry about?

Carl