Re: [PATCH 2/2] objtool: Support CROSS_COMPILE

From: Josh Poimboeuf
Date: Wed Mar 02 2016 - 22:21:06 EST


On Thu, Mar 03, 2016 at 01:43:14PM +1100, Stephen Rothwell wrote:
> Hi Josh,
>
> Just a couple of quick comments ...
>
> On Wed, 2 Mar 2016 18:39:37 -0600 Josh Poimboeuf <jpoimboe@xxxxxxxxxx> wrote:
> >
> > diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile
> > index c4f0713..e4a6bd5 100644
> > --- a/tools/objtool/Makefile
> > +++ b/tools/objtool/Makefile
>
> 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".

> > @@ -7,13 +7,19 @@ ARCH := x86
> > endif
> > endif
> >
> > +# always use the host compiler
> > +CC = gcc
>
> 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.

--
Josh