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Date:   Tue, 21 Jun 2022 16:15:04 +0200
From:   Cyril Hrubis <chrubis@suse.cz>
To:     David Laight <David.Laight@ACULAB.COM>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>,
        "linux-api@vger.kernel.org" <linux-api@vger.kernel.org>,
        "libc-alpha@sourceware.org" <libc-alpha@sourceware.org>,
        "arnd@arndb.de" <arnd@arndb.de>,
        "ltp@lists.linux.it" <ltp@lists.linux.it>,
        "zack@owlfolio.org" <zack@owlfolio.org>,
        "dhowells@redhat.com" <dhowells@redhat.com>
Subject: Re: [PATCH v3] uapi: Make __{u,s}64 match {u,}int64_t in userspace
Message-ID: <YrHSaLombzbJwLhF@yuki>
References: <20220621120355.2903-1-chrubis@suse.cz>
 <a26ab9bfc27a430bb8a7b6aa2f39d724@AcuMS.aculab.com>
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Hi!
> > This changes the __u64 and __s64 in userspace on 64bit platforms from
> > long long (unsigned) int to just long (unsigned) int in order to match
> > the uint64_t and int64_t size in userspace for C code.
> > 
> > We cannot make the change for C++ since that would be non-backwards
> > compatible change and may cause possible regressions and even
> > compilation failures, e.g. overloaded function may no longer find a
> > correct match.
> 
> Isn't is enough just to mention C++ name mangling?

I just picked up the argument that was brought up in the discussion
about the v1 patch and used it as a concrete example. Mangling is I
guess more straightforward example of a breakage. I can change the
description if there is consensus that such description would be better.

-- 
Cyril Hrubis
chrubis@suse.cz