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Subject: Re: [PATCH] Kconfig: default to CC_OPTIMIZE_FOR_PERFORMANCE_O3 for
 gcc >= 10
From:   Joe Perches <joe@perches.com>
To:     David Laight <David.Laight@ACULAB.COM>,
        Arnd Bergmann <arnd@arndb.de>,
        Oleksandr Natalenko <oleksandr@redhat.com>
Cc:     "Jason A. Donenfeld" <Jason@zx2c4.com>,
        LKML <linux-kernel@vger.kernel.org>, X86 ML <x86@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>
Date:   Sun, 10 May 2020 10:45:24 -0700
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On Sun, 2020-05-10 at 12:47 +0000, David Laight wrote:
> From: Joe Perches
> > Sent: 08 May 2020 16:06
> > 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?
> 
> When ever I've been anywhere near it it is always a disaster.

A disaster? Why?

For a large commercial c only project, it worked well
by reducing a combined multi-include file, similar to
kernel.h here, to a single file.

That was before SSDs though and the file open times
might have been rather larger then.