Re: Build regressions/improvements in v5.6

From: Guenter Roeck
Date: Mon Mar 30 2020 - 21:25:32 EST


On 3/30/20 2:17 PM, Vineet Gupta wrote:
> On 3/30/20 1:40 PM, Alexey Brodkin wrote:
>> Hi Andy, Geert,
>>
>>> -----Original Message-----
>>> From: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
>>> Sent: Monday, March 30, 2020 4:28 PM
>>> To: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>; Alexey Brodkin <abrodkin@xxxxxxxxxxxx>
>>> Cc: Linux Kernel Mailing List <linux-kernel@xxxxxxxxxxxxxxx>
>>> Subject: Re: Build regressions/improvements in v5.6
>>>
>>> On Mon, Mar 30, 2020 at 4:26 PM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
>>>>
>>>> Hi Andy,
>>>>
>>>> On Mon, Mar 30, 2020 at 3:08 PM Andy Shevchenko
>>>> <andy.shevchenko@xxxxxxxxx> wrote:
>>>>> On Mon, Mar 30, 2020 at 12:00 PM Geert Uytterhoeven
>>>>> <geert@xxxxxxxxxxxxxx> wrote:
>>>>>> Below is the list of build error/warning regressions/improvements in
>>>>>> v5.6[1] compared to v5.5[2].
>>>>>
>>>>>> + /kisskb/src/include/linux/dev_printk.h: warning: format '%zu' expects argument of type
>>> 'size_t', but argument 8 has type 'unsigned int' [-Wformat=]: => 232:23
>>>>>
>>>>> This is interesting... I checked all dev_WARN_ONCE() and didn't find an issue.
>>>>
>>>> arcv2/axs103_smp_defconfig
>>>>
>>>> It's probably due to a broken configuration for the arc toolchain.
>>>
>>> Alexey, do have any insight?
>>
>> I think I do have some but first I'd like to get it reproduced myself.
>> I just built v5.6 with help of both GCC 8.3.1- & 9.3.1-based toolchains
>> and didn't see a single warning. So I guess I was doing something wrong.
>>
>> FWIW
>>
>> 1. My GCC 8.3.1 toolchain was exactly this:
>> https://github.com/foss-for-synopsys-dwc-arc-processors/toolchain/releases/download/arc-2019.09-release/arc_gnu_2019.09_prebuilt_uclibc_le_archs_linux_install.tar.gz
>>
>> 2. Linux kernel is vanilla v5.6.0
>>
>> 3. Configured and built as simple as:
>> make axs103_smp_defconfig && make
>
> It seems the build service is using a arc toolchain built in 2016 :-)
>
> # < /opt/cross/kisskb/br-arcle-hs38-full-2016.08-613-ge98b4dd/bin/arc-linux-gcc
>
> Call it Murphy's law, same year a little later I'd fixed the same issue in gcc [1]
>
> [1] http://lists.infradead.org/pipermail/linux-snps-arc/2016-October/001661.html
>
> @Guenter could you please consider updating the ARC tools. FWIW you can build
> stuff off upstream gcc/binutils using build system of your choice.
>

I am currently using vanilla gcc 9.2.0 to build arc and arcv2 images. Are you saying
that I need to update to gcc 9.3.0 ? gcc 9.3.0 was released only a couple of weeks
ago. I don't usually jump onto new compiler releases that quickly because each
release tends to have regressions.

[ Never mind, I just noticed Geert's reply. Still.... ]

Guenter