Followup-For: Bug #824169 For the record, in nvidia-settings I worked around this problem by disabling the nvidia-settings-dbgsym/contrib package, but still building libxnvctrl0-dbgsym (which goes into main).
Please let me know if I can remove that workaround again. libxnvctrl-dev | 375.26-3 | unstable | amd64, arm64, armel, ... libxnvctrl0 | 375.26-3 | unstable | amd64, arm64, armel, ... libxnvctrl0-dbgsym | 375.26-3 | unstable-debug | amd64, arm64, armel, ... nvidia-settings | 375.26-3 | unstable | source nvidia-settings | 375.26-3 | unstable-debug | source nvidia-settings | 375.26-3 | unstable/contrib | amd64, armhf, i386 Andreas
