Re: [PATCH] ARC: build: Try to guess CROSS_COMPILE with cc-cross-prefix

[Vineet Gupta <Vineet.Gupta1@synopsys.com>]

On 6/12/19 4:17 AM, Masahiro Yamada wrote:
> Hi.
> 
> On Tue, Jun 4, 2019 at 2:49 AM Alexey Brodkin
> <Alexey.Brodkin@synopsys.com> wrote:
>>
>> Hi Vineet,
>>
>>> -----Original Message-----
>>> From: Vineet Gupta <vgupta@synopsys.com>
>>> Sent: Monday, June 3, 2019 7:25 PM
>>> To: Alexey Brodkin <abrodkin@synopsys.com>; linux-snps-arc@lists.infradead.org
>>> Cc: linux-kernel@vger.kernel.org; Masahiro Yamada <yamada.masahiro@socionext.com>
>>> Subject: Re: [PATCH] ARC: build: Try to guess CROSS_COMPILE with cc-cross-prefix
>>>
>>> On 6/2/19 11:31 PM, Alexey Brodkin wrote:
>>>> For a long time we used to hard-code CROSS_COMPILE prefix
>>>> for ARC until it started to cause problems, so we decided to
>>>> solely rely on CROSS_COMPILE externally set by a user:
>>>> commit 40660f1fcee8 ("ARC: build: Don't set CROSS_COMPILE in arch's Makefile").
>>>>
>>>> While it works perfectly fine for build-systems where the prefix
>>>> gets defined anyways for us human beings it's quite an annoying
>>>> requirement especially given most of time the same one prefix
>>>> "arc-linux-" is all what we need.
>>>>
>>>> It looks like finally we're getting the best of both worlds:
>>>>  1. W/o cross-toolchain we still may install headers, build .dtb etc
>>>>  2. W/ cross-toolchain get the kerne built with only ARCH=arc
>>>>
>>>> Inspired by [1] & [2].
>>>>
>>>> [1] http://lists.infradead.org/pipermail/linux-snps-arc/2019-May/005788.html
>>>> [2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=fc2b47b55f17
>>>>
>>>> A side note: even though "cc-cross-prefix" does its job it pollutes
>>>> console with output of "which" for all the prefixes it didn't manage to find
>>>> a matching cross-compiler for like that:
>>>> | # ARCH=arc make defconfig
>>>> | which: no arceb-linux-gcc in (~/.local/bin:~/bin:/usr/bin:/usr/sbin)
>>>> | *** Default configuration is based on 'nsim_hs_defconfig'
> 
> 
> I just noticed this patch is queued on top of v5.2-rc4.
> (2bc42bfba9b247abd)
> 
> This 'side note' is no longer needed or reproducible
> because -rc4 contains my fix-up (913ab9780fc0212).

But 2bc42bfba9b247abd was to address my complaint that we need to specify
CROSS_COMPILE prefix on cmdline.

When doing the needful Alexey found the "noise" when a prefix didn't exist, which
913ab9780fc0212 address.

So these seem like orthogonal to me - that is unless I got the wired crossed somewhow.

> 
> I do not know if the ARC maitainer is happy to rebase.

I would happily do that on next rc if that is infact needed.