Fix build with clang
Fix build with clang

decltype(*static_cast<Derived*>(this)) is invalid - for now assume that intersect(ray, bvh) always returns hit_record<R, primitive>

ukoeln-vis/ctpperf,ukoeln-vis/ctpperf,tu500/visionaray,tu500/visionaray,szellmann/visionaray,szellmann/visionaray