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Date:   Tue, 18 Feb 2020 10:37:52 +0100
From:   Philipp Rudo <prudo@linux.ibm.com>
To:     Jeremy Cline <jcline@redhat.com>
Cc:     Masahiro Yamada <masahiroy@kernel.org>,
        Michal Kubecek <mkubecek@suse.cz>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Heiko Carstens <heiko.carstens@de.ibm.com>,
        Vasily Gorbik <gor@linux.ibm.com>,
        linux-s390 <linux-s390@vger.kernel.org>
Subject: Re: s390 depending on cc-options makes it difficult to configure
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Hi Masahiro,


On Sun, 16 Feb 2020 13:57:59 -0500
Jeremy Cline <jcline@redhat.com> wrote:

> On Sun, Feb 16, 2020 at 01:08:49PM +0900, Masahiro Yamada wrote:
> > On Sat, Feb 15, 2020 at 5:35 AM Jeremy Cline <jcline@redhat.com> wrote:  
> > >
> > > On Fri, Feb 14, 2020 at 12:31:05PM +0900, Masahiro Yamada wrote:  
> > > > Hi.
> > > >
> > > > On Tue, Feb 11, 2020 at 3:49 AM Philipp Rudo <prudo@linux.ibm.com> wrote:  

[...]

> > > > One idea to workaround this is
> > > > to use a fake script that accepts any flag,
> > > > and use it as $(CC) in Kconfig.
> > > >
> > > > RFC patch is attached.
> > > >
> > > > This is not a perfect solution, of course.

I like the approach as it gives both sides what they need without blowing up
Kconfig.

> > > The attached patch doesn't looks like it'd work for what we need,  
> > 
> > I thought turning all cc-options to y would work
> > for what you need.
> > 
> > With this, you can enable
> > CONFIG_MARCH_Z13=y and CONFIG_TUNE_Z14=y
> > instead of CONFIG_TUNE_DEFAULT.
> > 
> > If this approach does not work for you,
> > what is your requirement?
> >   
> 
> Oof, this was an awful typo. It *would* work for what we need. Sorry for
> the confusion :(.
> 
> > 
> >   
> > > although I wonder if it's easier to just check when cc-options is
> > > defined for an environment variable or something and always return y
> > > instead of calling out to $(CC) at all. Comes to the same thing, I
> > > suppose.  
> > 
> > 
> > The macro definition in scripts/Kconfig.include
> > takes precedence over any environment variable.
> > 
> > So, if you want to hack it from the environment,
> > you need to change the code somehow.
> > 
> > The scripts/dummy-tools/ approach does not change
> > anything for the use-case in upstream.
> > 
> > The result is the same, of course.
> >   
> 
> Indeed. Since I'm not maintaining it I don't have a particularly strong
> opinion about the approach. Whatever you like most works for me.

I agree with Jeremy. Just pick what you think is best.

Thanks a lot
Philipp