Re: [v4l-utils v5 0/5] Add support for meson building

[Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>]

Hi,

On 12/05/2021 21:49, Ariel D'Alessandro wrote:
> Hi all,
> 
> Another attempt to support meson build, addressing comments/fixes from
> reviewers.
> 
> This patchset was developed on top of v4l-utils current master branch:
> 
>      commit f0c7e3d71eaf4182bae7eb3ee0e43b4eeb047ea9
>      Author: Hans Verkuil <hverkuil-cisco@xs4all.nl>
> 
>          v4l2-ctl: add '--set-edid type=list' support
> 
> You can find the patchset pushed to the following branch:
> 
>      https://gitlab.collabora.com/adalessandro/v4l-utils/-/tree/v4l-utils-meson-v5
> 
> Feedback appreciated as always :-)

I was testing this (well, I'm using it, as I can't get the autoconf work with
cross-compilation..), and I see this problem if gconv is enabled when
cross-compiling for arm (buildroot system):

[1/2] Linking target contrib/gconv/EN300-468-TAB00.so
FAILED: contrib/gconv/EN300-468-TAB00.so
/home/tomba/work/buildroot/output32/host/bin/arm-buildroot-linux-gnueabihf-gcc  -o contrib/gconv/EN300-468-TAB00.so contrib/gconv/EN300-468-TAB00.so.p/en300-468-tab00.c.o -Wl,--as-needed -Wl,--allow-shlib-undefined -shared -fPIC -Wl,-rpath,/usr/lib/x86_64-linux-gnu/gconv -Wl,-rpath-link,/usr/lib/x86_64-linux-gnu/gconv -Wl,--start-group /usr/lib/x86_64-linux-gnu/gconv/libJIS.so /usr/lib/x86_64-linux-gnu/gconv/libJISX0213.so -Wl,--end-group
/usr/lib/x86_64-linux-gnu/gconv/libJIS.so: file not recognized: file format not recognized
collect2: error: ld returned 1 exit status
[2/2] Linking target contrib/gconv/ARIB-STD-B24.so
FAILED: contrib/gconv/ARIB-STD-B24.so
/home/tomba/work/buildroot/output32/host/bin/arm-buildroot-linux-gnueabihf-gcc  -o contrib/gconv/ARIB-STD-B24.so contrib/gconv/ARIB-STD-B24.so.p/arib-std-b24.c.o -Wl,--as-needed -Wl,--allow-shlib-undefined -shared -fPIC -Wl,-rpath,/usr/lib/x86_64-linux-gnu/gconv -Wl,-rpath-link,/usr/lib/x86_64-linux-gnu/gconv -Wl,--start-group /usr/lib/x86_64-linux-gnu/gconv/libJIS.so /usr/lib/x86_64-linux-gnu/gconv/libJISX0213.so -Wl,--end-group
/usr/lib/x86_64-linux-gnu/gconv/libJIS.so: file not recognized: file format not recognized

Also, would this be better, to be a bit more explicit:

-    '-I.', # Needed for config.h
+    '-I' + meson.global_build_root(), # Needed for config.h

I would do the same to other ".." paths too, but maybe that's just a personal
preference:

-Icontrib/test/v4l2gl.p -Icontrib/test -I../contrib/test -I../lib/include -I../include -I.

I also wonder what the "-Icontrib/test" is for.

I also see a problem when cross-compiling where a wrong config.h is included. When
compiling with buildroot env, valgrind include dir is in the include paths. And valgrind
has a "config.h" there...

It would be safer to have the "-I." common flag before all the rest of the parameters,
instead of being after all the others, but I didn't immediately find out how to do
that with meson.

  Tomi