From 21ae07e7cd7b54967d8e486e2b443816debe7fa1 Mon Sep 17 00:00:00 2001
From: Alejandro Colomar <alx@kernel.org>
Date: Tue, 11 Apr 2023 22:13:00 +0200
Subject: sockaddr.3type: POSIX Issue 8 will solve strict-aliasing issues with
 these types
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Link: <https://austingroupbugs.net/view.php?id=1641>
Reported-by: Bastien Roucariès <rouca@debian.org>
Reported-by: Alejandro Colomar <alx@kernel.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Cc: glibc <libc-alpha@sourceware.org>
Cc: GCC <gcc@gcc.gnu.org>
Cc: Stefan Puiu <stefan.puiu@gmail.com>
Cc: Igor Sysoev <igor@sysoev.ru>
Cc: Rich Felker <dalias@libc.org>
Cc: Andrew Clayton <andrew@digital-domain.net>
Cc: Richard Biener <richard.guenther@gmail.com>
Cc: Zack Weinberg <zack@owlfolio.org>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Joseph Myers <joseph@codesourcery.com>
Cc: Jakub Jelinek <jakub@redhat.com>
Cc: Sam James <sam@gentoo.org>
Signed-off-by: Alejandro Colomar <alx@kernel.org>
---
 man3type/sockaddr.3type | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/man3type/sockaddr.3type b/man3type/sockaddr.3type
index 2fdf56c59..cf8d601f5 100644
--- a/man3type/sockaddr.3type
+++ b/man3type/sockaddr.3type
@@ -117,6 +117,14 @@ POSIX.1-2001.
 was invented by POSIX.
 See also
 .BR accept (2).
+.PP
+These structures were invented before modern ISO C strict-aliasing rules.
+If aliasing rules are applied strictly,
+these structures would be extremely difficult to use
+without invoking Undefined Behavior.
+POSIX Issue 8 will fix this by requiring that implementations
+make sure that these structures
+can be safely used as they were designed.
 .SH NOTES
 .I socklen_t
 is also defined in
-- 
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