[Buildroot] [PATCH v2] libepoxy: OpenGL EGL and OpenGL ES dependencies are mandatory

[Thomas Petazzoni]

Hello,

On Thu, 23 Mar 2017 10:00:59 -0300, Gustavo Zacarias wrote:
> On 2017-03-22 18:56, Thomas Petazzoni wrote:
> 
> >> Also, libepoxy use dlsym to load a GLES2 library when EGL support is
> >> enabled, see src/dispatch_common.c:
> >> 
> >> So, OpenGL ES dependency is also mandatory.
> >> 
> >> Fixes:
> >>   
> >> http://autobuild.buildroot.net/results/3eca5ba26a521f6cc5a611309ba066472af7769c
> >>   
> >> http://autobuild.buildroot.net/results/cf9ec7da196d70548ae1413e4a3730314f6434d6
> >>   
> >> http://autobuild.buildroot.net/results/069b80101afc4719db6d6d41cf5fc923be21ddc0
> >> 
> >> Signed-off-by: Vicente Olivert Riera <Vincent.Riera at imgtec.com>
> >> Reviewed-by: Romain Naour <romain.naour at gmail.com>
> >> Tested-by: Romain Naour <romain.naour at gmail.com>  
> > 
> > I would really like to hear about this patch from Gustavo. Gustavo,
> > could you review/comment?  
> 
> Hi all.
> According to my tests this isn't a hard requirement - libepoxy builds 
> and works fine with just EGL, in fact a PoC is pretty easy, just clone 
> http://repo.or.cz/buildroot-gz.git/shortlog/refs/heads/desktop, make 
> pc_x86_64_bios_wayland_defconfig, make menuconfig, disable GLES, build 
> and the resulting image which is wayland-weston-midori (hence gtk3, plus 
> some other gtk3 apps) works just fine.
> And by looking at the source i don't see where in dispatch_common.c the 
> lack of GLES errors out hard.

Then what is your proposal to fix the build issues that this patch is
trying to fix? The build log clearly points to missing EGL as being the
issue:

checking for EGL... no
configure: error: Package requirements (egl) were not met:

Package egl was not found in the pkg-config search path.
Perhaps you should add the directory containing `egl.pc'
to the PKG_CONFIG_PATH environment variable
Package 'egl', required by 'world', not found

Consider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.

Alternatively, you may set the environment variables EGL_CFLAGS
and EGL_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.
make[1]: *** [/home/buildroot/autobuild/run/instance-2/output/build/libepoxy-1.4.1/.stamp_configured] Error 1
make: *** [_all] Error 2
make: Leaving directory `/home/buildroot/autobuild/run/instance-2/buildroot'

Best regards,

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com