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To: Arnd Bergmann <arnd@arndb.de>, x86@kernel.org
From: Chris Wilson <chris@chris-wilson.co.uk>
In-Reply-To: <20180202145434.100626-1-arnd@arndb.de>
Cc: "Nicolas Pitre" <nico@linaro.org>, "Andi Kleen" <ak@linux.intel.com>,
        linux-kernel@vger.kernel.org, "Arnd Bergmann" <arnd@arndb.de>
References: <20180202145434.100626-1-arnd@arndb.de>
Message-ID: <151821507347.9954.4785393248908071074@mail.alporthouse.com>
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Subject: Re: [PATCH 0/3] x86 bugfixes for LTO
Date: Fri, 09 Feb 2018 22:24:33 +0000
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Quoting Arnd Bergmann (2018-02-02 14:54:28)
> Here are three bugfixes for x86 that I needed to get LTO-enabled
> kernels to build reliably. I'm not sure abouto that first one
> though.

Is there a howto on how to build LTO kernels? I tried Andi's lto-415-2
branch, but linking fails with lots of arcane PIE-vs-PIC errors. We are
wanting to investigate how we can use LTO to reduce our (i915.ko) module
size (by e.g. supporting a subset of chipsets).
-Chris