fbdev_drv.so: undefined symbol: shadowUpdatePackedWeak, xinit: giving up raspberrypi3_defconfig Cant Startx Bug reported https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=900613
In Rpi3 case fbdev version 0.5.0 seems to solve problem
This bug should be closed, I assume that https://git.buildroot.net/buildroot/commit/package/x11r7/xdriver_xf86-video-fbdev?id=904750363141935dc6b1143aaa1de21742df474a has fixed it.
Closed, thanks