[U-Boot] [PATCH] tools/Makefile: fix HOSTCFLAGS with CROSS_BUILD_TOOLS

[Fabrice Fontaine]

Le dim. 25 août 2019 à 16:11, Jan Kiszka <jan.kiszka at web.de> a écrit :
>
> On 25.08.19 15:43, Fabrice Fontaine wrote:
> > Hello,
> > Le dim. 25 août 2019 à 13:44, Jan Kiszka <jan.kiszka at web.de> a écrit :
> >>
> >> On 01.05.19 15:08, Fabrice Fontaine wrote:
> >>> When CROSS_BUILD_TOOLS is set, set HOSTCFLAGS to CFLAGS otherwise CC
> >>> will be used with HOSTCFLAGS which seems wrong
> >>>
> >>> Signed-off-by: Fabrice Fontaine <fontaine.fabrice at gmail.com>
> >>> ---
> >>>    tools/Makefile | 1 +
> >>>    1 file changed, 1 insertion(+)
> >>>
> >>> diff --git a/tools/Makefile b/tools/Makefile
> >>> index 12a3027e23..eadeba417d 100644
> >>> --- a/tools/Makefile
> >>> +++ b/tools/Makefile
> >>> @@ -272,6 +272,7 @@ subdir- += env
> >>>
> >>>    ifneq ($(CROSS_BUILD_TOOLS),)
> >>>    override HOSTCC = $(CC)
> >>> +override HOSTCFLAGS = $(CFLAGS)
> >>>
> >>>    quiet_cmd_crosstools_strip = STRIP   $^
> >>>          cmd_crosstools_strip = $(STRIP) $^; touch $@
> >>>
> >>
> >> This eats - among other things - -O2, normally set in /Makefile. And that breaks
> >> CROSS_BUILD_TOOLS=y with CONFIG_FIT but without CONFIG_FIT_SIGNATURE because "if
> >> (!IMAGE_ENABLE_SIGN)" is no longer optimized. I tend to believe this should
> >> simply be reverted (which is what I'm doing locally in order to fix my builds).
> > I don't think this patch should be reverted, I sent it to fix a
> > cross-compilation build issue with host-openssl.
> >
> > Indeed, without this patch, with CROSS_BUILD_TOOLS=y, tools/Makefile
> > sets HOSTCC=$(CC) but it forgets
> > to override HOSTCFLAGS, though, so the tools are built with target
> > compiler but host CFLAGS.
> >
> > This raises a build failure if host-openssl is built before uboot-tools because
> > uboot-tools links with openssl headers from host which depends on pthread.h
> >
> > More information can be found on buildroot's patchwork here:
> > - https://patchwork.ozlabs.org/patch/1092227
> > - https://patchwork.ozlabs.org/patch/1093385
> >>
> >> Jan
> >
> > Best Regards,
> >
> > Fabrice
> >
>
> So what is your suggestion to fix the O2-regression best?
I'm far from being an expert in uboot so please excuse me if my answer
contains some mistakes.
However, IMHO, we should not pass -O2 or any other optimization flags.
>From my understanding, CFLAGS (and so HOSTCFLAGS when building tools
for the target through cross-tools) will (or should?) contain -O2 or
-Os depending on CONFIG_CC_OPTIMIZE_FOR_SIZE value.
However, I do understand that this is a change in the former behavior
that was always passing -O2 in HOSTCFLAGS.
So, if you really want to pass -O2, I would add it to HOSTCFLAGS in
tools/Makefile (after the override).
However, I have to confess that I don't understand why the build
breaks "if (!IMAGE_ENABLE_SIGN)" is no longer optimized."
>
> Jan

Fabrice