What does this error mean?
For a user, it means: “You’re screwed.”
For a developer, it means: “You screwed up, or maybe the driver screwed up, time to debug!”.
The situations in which that error can occur are so numerous, it’s impossible to answer why it occured with just the information you have given. You don’t really care what went wrong anyway, you just want it to work.
File a bug report with as much information as possible, include the .blend file, include which GPU you use on which OS and driver. If your GPU is supported (i.e. if it’s not some 1GB pre-GCN model), it may be accepted as a bug and possibly fixed. If your GPU is not supported, that’s just Blender not bothering to handle these errors appropriately (which would be quite a bit of work!).
Well gee mate, not everyone is a developer and cares about technicality behind errors.
I should have given more info, you’re right.
Anyway thanks for the reply 