Whoops, fat-fingered submit button before I filled this in. Sorry.

Mesa version is 17.2.1

If I play this trace on an i915 Skylake system, the lighting on the landscape
is flickery and weird when the camera moves. If I export
LIBGL_ALWAYS_SOFTWARE=1 and play the trace, everything renders as it should.

Here's the apitrace output:

https://www.uplinklabs.net/files/darwinia-trace.log.gz