Redefinition of struct in6_addr in <netinet/in.h> and <linux/in6.h>

[David Miller]

From: Rich Felker <dalias@aerifal.cx>
Date: Wed, 16 Jan 2013 15:42:12 -0500

> It's a bug for the kernel uapi headers to define any type, macro, or
> structure tag that's supposed to be defined by libc.

But we've provided these types in the kernel headers for decades, and
if we stop exporting them we equally risk breaking existing builds
that are working properly.

So you can't just say, "get rid of the kernel header definitions of
these things", that simply won't work.

Every "solution" proposed thus far breaks things for somebody, that's
why this issue hasn't been addressed in any way yet.