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

From: Masahiro Yamada
Date: Mon Jun 03 2019 - 04:22:45 EST

Hi Alexey,

On Mon, Jun 3, 2019 at 3:42 PM Alexey Brodkin
<Alexey.Brodkin@xxxxxxxxxxxx> 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]
> [2]
> 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'

Oh really?

masahiro@pug:~$ which arc-linux-gcc
masahiro@pug:~$ which dummy-linux-gcc
masahiro@pug:~$ echo $?

When 'which' cannot find the given command,
it does not print anything to stderr.

Does it work differently on your machine?

Best Regards
Masahiro Yamada