i'm getting a an error
Device not supported: "gfx900", only AMD GCN cards are supported.
it's a Radeon Vega56

Hi!
Is it on Windows or on Linux?
Thanks
additional details...
gfx900 is when HBCC is turned off does not work when HBCC turned off
gfx901 is when HBCC is turned on. it works with HBCC turned on
running 18.10.2 drivers now.
have you tried developing without the blockchain drivers? the blockchain drivers are supported in the latest released drivers and they're more stable.
and have you tried developing with HBCC off.
HBCC are for the vega cards. the 500 and 400 series card have a compute/graphic switch in AMD settings window.