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Subject: Re: [PATCH v3 14/17] PCI: dwc: artpec6: Add support for endpoint mode
To: Arnd Bergmann <arnd@arndb.de>
CC: Bjorn Helgaas <bhelgaas@google.com>, Jesper Nilsson <jespern@axis.com>,
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From: Niklas Cassel <niklas.cassel@axis.com>
Message-ID: <c87b2ef1-9bb4-cb1b-872d-bb234e14511e@axis.com>
Date: Fri, 3 Nov 2017 15:16:20 +0100
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On 11/03/2017 11:23 AM, Arnd Bergmann wrote:
> On Fri, Nov 3, 2017 at 10:56 AM, Niklas Cassel <niklas.cassel@axis.com> wrote:
>> On 11/02/2017 10:13 AM, Arnd Bergmann wrote:

> What I meant is that you can remove the #ifdef entirely if you add
> 
>          if (!IS_ENABLED(CONFIG_PCIE_ARTPEC6_HOST))
>                   return -ENODEV;
> 
> to artpec6_pcie_probe(). Anything after that statement will get
> silently dropped by the compiler, including static functions and
> structures that are referenced indirectly from there.

Wow, this actually helps gcc with dead code elimination.
It was even possible to add those !IS_ENABLED the two different
case labels in the switch statement.
I get no unwanted symbols when looking at the vmlinux in gdb.

Great suggestion Arnd :)


Regards,
Niklas