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From:   Arnd Bergmann <arnd@arndb.de>
Date:   Fri, 8 May 2020 17:09:14 +0200
Message-ID: <CAK8P3a2KU_4FVCYt73mmpodV3Q7ipS579BDMnai-m9HgaiFYiA@mail.gmail.com>
Subject: Re: [PATCH] Kconfig: default to CC_OPTIMIZE_FOR_PERFORMANCE_O3 for
 gcc >= 10
To:     Joe Perches <joe@perches.com>
Cc:     Oleksandr Natalenko <oleksandr@redhat.com>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>,
        LKML <linux-kernel@vger.kernel.org>, X86 ML <x86@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>
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On Fri, May 8, 2020 at 5:06 PM Joe Perches <joe@perches.com> wrote:
>
> On Fri, 2020-05-08 at 13:49 +0200, Arnd Bergmann wrote:
> > Personally, I'm more interested in improving compile speed of the kernel
>
> Any opinion on precompiled header support?

I have not tried it. IIRC precompiled headers usually work best for projects
that have a large header with all the global declarations that gets included
everywhere, while Linux has always tried (with different amounts of success)
to minimize the number of headers that get included per file.

       Arnd