Opened /dev/tty3
Ran $ weston-launch -- --use-egl-device
output:

weston 1.12.0
...
Build: 1.11.94-2-ga08dff5 configure.ac: bump to version 1.12.0 for the official release (2016-09-20 12:22:46 -0700)
Command line: /usr/bin/weston --use-egl-device
OS: Linux, 4.7.6-1-ARCH, #1 SMP PREEMPT Fri Sep 30 19:28:42 CEST 2016, x86_64
Using config file '/home/[...]/.config/weston.ini'
Output repaint window is 7 ms maximum.
Loading module '/usr/lib/libweston-1/drm-backend.so'
initializing drm backend
logind: session control granted
using /dev/dri/card0
Loading module '/usr/lib/libweston-1/gl-renderer.so'
EGL client extensions: EGL_KHR_client_get_all_proc_addresses
EGL_EXT_client_extensions EGL_EXT_platform_base
EGL_EXT_platform_x11 EGL_EXT_platform_wayland
EGL_EXT_platform_device EGL_EXT_device_base
failed to initialize egl
fatal: Failed to create compositor backend


I don't know if this is helpful, but I hope so. I would like to contribute in some way. Thanks