[Buildroot] [PATCH 1/1] libv4l: needs kernel headers >= 3.18

[Fabrice Fontaine]

Dear Peter,
Le ven. 2 nov. 2018 à 15:20, Peter Seiderer <ps.report at gmx.net> a écrit :
>
> Hello Fabrice,
>
> On Fri,  2 Nov 2018 14:35:21 +0100, Fabrice Fontaine <fontaine.fabrice at gmail.com> wrote:
>
> > Bump to version 1.16.1 added a dependency to bpf headers:
> > https://git.linuxtv.org/v4l-utils.git/commit/?id=d6025b0e8c7f57b0f9390f987acc5eed57360d80
> >
> > BPF headers are available since kernel 3.18:
> > https://github.com/torvalds/linux/commit/c15952dc18d8a293d976ac6c06d44d9d98023b45
> >
> > Fixes:
> >  - http://autobuild.buildroot.org/results/d22c0939eed4bc949f7eaeae7595d01ec45cc2cd
> >
>
> Thanks for taking care of the autobuild failure, but....
>
> To be exact, only utils/keytable depend on the (new) linux kernel bpf header, so
> it would be sufficient for only v4l-utils to depend on headers >= 3.18 (or split
> v4l-utils into the single utils with different dependencies)?
Yes, you're right, at least I should have moved this dependency to the
utils option.
>
> Or: the commit d6025b0e8c7f57b0f9390f987acc5eed57360d80 adds already a copy
> of the linux/bpf.h header, maybe only the dependent linux/bpf_common.h file is
> missing?
Indeed, I think this is the best solution. I will set this patch as
rejected and let you send a new patch.

We have an other build failure with this bump:
http://autobuild.buildroot.org/results/c18/c18fb7f1ac81496db9c3a4e91ea028a26ca600b0/build-end.log

This build failure is due to the clang dependency that has been added with:
https://git.linuxtv.org/v4l-utils.git/commit/?id=91b37c0d9cb71fc2d5f78cc96aa2ef9f3bba145b

I'm trying to fix it but I don't know if this will be easy as I'm not
familiar with clang.
At least, we'll have to add host-clang (which is a "big" dependency)
and remove or customize the "-target bpf" in the following command
line:
$(CLANG) $(CLANG_SYS_INCLUDES) -I$(top_srcdir)/include -target bpf -O2 -c $<

An other option would be to disable BPF protocols for the time being
by setting ac_cv_prog_CLANG to "".
Do you have an opinion on this one?
>
> Regards,
> Peter
>
> > Signed-off-by: Fabrice Fontaine <fontaine.fabrice at gmail.com>
> > ---
> >  package/libv4l/Config.in   | 2 +-
> >  package/v4l2grab/Config.in | 2 +-
> >  package/zbar/Config.in     | 2 +-
> >  3 files changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/package/libv4l/Config.in b/package/libv4l/Config.in
> > index 57ddde1dfb..84844349a4 100644
> > --- a/package/libv4l/Config.in
> > +++ b/package/libv4l/Config.in
> > @@ -2,7 +2,7 @@ config BR2_PACKAGE_LIBV4L
> >       bool "libv4l"
> >       depends on BR2_TOOLCHAIN_HAS_THREADS
> >       depends on BR2_INSTALL_LIBSTDCPP
> > -     depends on BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_0 # media headers
> > +     depends on BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_18 # bpf headers
> >       select BR2_PACKAGE_ARGP_STANDALONE if BR2_TOOLCHAIN_USES_UCLIBC || BR2_TOOLCHAIN_USES_MUSL
> >       select BR2_PACKAGE_LIBICONV if !BR2_ENABLE_LOCALE
> >       help
> > diff --git a/package/v4l2grab/Config.in b/package/v4l2grab/Config.in
> > index ec3a7a8c54..e25b1618e8 100644
> > --- a/package/v4l2grab/Config.in
> > +++ b/package/v4l2grab/Config.in
> > @@ -4,7 +4,7 @@ config BR2_PACKAGE_V4L2GRAB
> >       depends on BR2_USE_MMU # libv4l
> >       depends on !BR2_STATIC_LIBS # libv4l
> >       depends on BR2_INSTALL_LIBSTDCPP # libv4l
> > -     depends on BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_0 # libv4l
> > +     depends on BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_18 # libv4l
> >       select BR2_PACKAGE_JPEG
> >       select BR2_PACKAGE_LIBV4L
> >       help
> > diff --git a/package/zbar/Config.in b/package/zbar/Config.in
> > index 05c9b769ce..1d8f1be7cf 100644
> > --- a/package/zbar/Config.in
> > +++ b/package/zbar/Config.in
> > @@ -3,7 +3,7 @@ config BR2_PACKAGE_ZBAR
> >       depends on BR2_TOOLCHAIN_HAS_THREADS # libv4l
> >       depends on BR2_USE_MMU # libv4l
> >       depends on BR2_INSTALL_LIBSTDCPP # libv4l
> > -     depends on BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_0 # libv4l
> > +     depends on BR2_TOOLCHAIN_HEADERS_AT_LEAST_3_18 # libv4l
> >       select BR2_PACKAGE_JPEG
> >       select BR2_PACKAGE_LIBV4L
> >       help
>
Best Regards,

Fabrice