Em Wed, May 20, 2015 at 06:16:51PM +0200, Martin Liška escreveu: > On 05/20/2015 04:55 PM, Ingo Molnar wrote: > >* Arnaldo Carvalho de Melo <a...@kernel.org> wrote: > >>So the rule has been: What are the kernel requirements for the > >>toolchain? tools/perf/ should build with that. > > > >So we could use -Og if it works, like Kbuild does it: > > > > KBUILD_CFLAGS += $(call cc-option,-mno-fp-ret-in-387) > > > >the 'cc-option' Make function does some magic of silently calling GCC > >with that option and observing the result.
> >See: > > scripts/Kbuild.include:cc-option = $(call try-run,\ > I am sorry, I did mistake in understanding of DEBUG variable. > Following patch should be fixed, except missing auto-detection > of -Og option. > > Unfortunately, following hunk does not work, no -Ox is added to CFLAGS? > > -- CFLAGS += -Og > ++ CFLAGS += $(call cc-option,-Og,-O0) I don't know if we have this cc-option, perhaps Ingo is suggesting we get it in tools/build/? Or include scripts/Kbuild.include and then use it? I.e. we have checks to see if we can use, for instance -fstack-protector-all, see tools/build/feature/Makefile, usong this cc-option thing, importing it from Kbuild would solve the issue at hand in a definitive way and in line with what we have been pursuing: to make the tools/ build system be based on Kbuild. - Arnaldo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
