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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Wed, 13 Nov 2019 11:04:03 +0100
Message-ID: <CAK8P3a0ikEMP6MQzL8QPMTgdA-euf7_AsFZAbxkDbFh=smMuaQ@mail.gmail.com>
Subject: Re: [PATCH 31/33] powerpc/64: make buildable without CONFIG_COMPAT
To:     =?UTF-8?Q?Michal_Such=C3=A1nek?= <msuchanek@suse.de>
Cc:     Nicholas Piggin <npiggin@gmail.com>,
        linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Allison Randal <allison@lohutok.net>,
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On Wed, Nov 13, 2019 at 9:41 AM Michal Suchánek <msuchanek@suse.de> wrote:
>
> On Wed, Nov 13, 2019 at 01:02:34PM +1000, Nicholas Piggin wrote:

> > >
> > > @@ -277,7 +276,7 @@ static void do_signal(struct task_struct *tsk)
> > >
> > >     rseq_signal_deliver(&ksig, tsk->thread.regs);
> > >
> > > -   if (is32) {
> > > +   if (is_32bit_task()) {
> > >             if (ksig.ka.sa.sa_flags & SA_SIGINFO)
> > >                     ret = handle_rt_signal32(&ksig, oldset, tsk);
> > >             else
> >
> > This is just a clean up I guess.
>
> It also expands directly to if(0) or if(1) for the !COMPAT cases. I am
> not sure how it would work with the intermediate variable.
>
> There was more complex change initially but after some additional
> cleanups removing the variable is the only part left.

I would be surprised if that made any difference to a modern compiler,
but the new version is definitely clearer to human readers.

       Arnd