Date: Wed, 2 Mar 2016 21:46:05 -0600
From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Ingo Molnar <mingo@redhat.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org,
        Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>, "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH 2/2] objtool: Support CROSS_COMPILE
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On Thu, Mar 03, 2016 at 02:38:43PM +1100, Stephen Rothwell wrote:
> Hi Josh,
> 
> On Wed, 2 Mar 2016 21:20:58 -0600 Josh Poimboeuf <jpoimboe@redhat.com> wrote:
> >
> > On Thu, Mar 03, 2016 at 01:43:14PM +1100, Stephen Rothwell wrote:
> > > 
> > > I was wondering if this would be more appropriate in scripts/objtool
> > > since it is used during the building of the kernel.  Or does it have a
> > > wider use?  
> > 
> > Yeah, it was actually in the scripts/ dir in earlier revisions of the
> > patch set, for that very reason.  However, Ingo pointed out that it
> > could be useful beyond the kernel, so we graduated it to a "tool".
> > 
> > > 
> > > We have HOSTCC with its associated HOSTCFLAGS etc ... I am not sure if
> > > that is more appropriate (but it does take care of people using clang).  
> > 
> > The "tools" are almost completely separate from the rest of the kernel.
> > They have their own scaled-down version of kbuild, which doesn't have
> > HOSTCC.
> > 
> > But yeah, we might eventually need to copy some of the host compilation
> > infrastructure from scripts/Makefile.host over to the tools/ side.
> 
> That all sounds sane, thanks.
> 
> I did not add this to linux-next today, but may tomorrow if people
> think it is sensible to do so (for testing on a powerpcle host).  If I
> do, I will just back out to the previous patch if it all goes south (so
> it won't impact on the rest of the tip tree's testing).

Sounds good, thanks!

FWIW, I did test it on a ppc64le host with an x86 cross-compiler and it
worked fine (but more testing is certainly welcome).

-- 
Josh