Re: [PATCH 0/4] Compile kernel with -fwhole-program --combine

David Woodhouse
2006-08-25T10:15:15Z

On Fri, 2006-08-25 at 09:26 +0200, Sam Ravnborg wrote:
> And this discussion is btw. mood. If the general opinion is that we shall
> include the -combine support all the kbuild infrastructure will anyway
> be redone.
> There are several small things that are not addressed in todays
> implementation and that will be fixed one way or the other.

There's a few _big_ things that aren't addressed in my makefile hack
either. It's very much a proof of concept.

However, if we limit the use of --combine to files within the same
directory, the modifications to the kbuild infrastructure shouldn't be
too intrusive. I strongly suspect that files within the same directory
are where the majority of the benefit is anyway.

Whole-kernel optimisation is likely to be prohibitively expensive, and
can wait for LTO¹.

--
dwmw2
¹ http://www.gelato.org/pdf/apr2006/gelato_ICE06apr_lto_mitchell_codesourcery.pdf