Re: [PATCH] ARM: dont specify STACKPROTECTOR in defconfigs

From: Paul Gortmaker
Date: Thu Jul 21 2016 - 14:05:21 EST


[Re: [PATCH] ARM: dont specify STACKPROTECTOR in defconfigs] On 22/07/2016 (Fri 01:40) Joel Stanley wrote:

> Hi Paul,
>
> On Fri, Jul 22, 2016 at 12:41 AM, Paul Gortmaker
> <paul.gortmaker@xxxxxxxxxxxxx> wrote:
> > Note the output from the following:
> >
> > $ git grep STACKPROTECTOR arch/arm/configs/
> > arch/arm/configs/aspeed_g4_defconfig:CONFIG_CC_STACKPROTECTOR_STRONG=y
> > arch/arm/configs/aspeed_g5_defconfig:CONFIG_CC_STACKPROTECTOR_STRONG=y
> > arch/arm/configs/bcm2835_defconfig:CONFIG_CC_STACKPROTECTOR_REGULAR=y
> > $
> >
> > Only three defconfigs specify a value. And two of the three ask for
> > the strong variant, which isn't supported by older toolchains.
> >
> > Due to the nature of ARM having more platform specific code than say
> > x86, the allyesconfig and allmodconfig aren't as effective for build
> > coverage. So, in addition, I like to use a trivial script to walk all
> > the defconfigs and build each one.
> >
> > However I will get false positives on unsupported stackprotector values
> > with an older toolchain like gcc-4.6.3. As in this instance I am just
> > using the compiler as a glorified syntax checker on a machine where I
> > build a bunch of other arch for the same reason, there is no real
> > motivation to get a newer toolchain for improved optimization etc.
>
> I'm happy to remove it from the Aspeed configurations as I'm not sure
> why it was enabled in the first place.
>
> However, I do not agree with the reasoning here. If you're building to
> check syntax a modern GCC will certainly pick up on more than one from
> four years ago.

Just to clarify, syntax in this case is just for fat fingered typos and
ensuring functions resolve with the appropriate header includes. If I
was coding new stuff specifically for ARM, then that would be different.

>
> > Since there are only three of them, and there is nothing about these
> > settings that are board/platform specific, I propose we just eliminate
> > the three existing instances and take the default.
>
> This makes sense to me.
>
> Acked-by: Joel Stanley <joel@xxxxxxxxx>

Thanks,
Paul.
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