Should WebGPU require an error when it can analyze erroneous non-uniformity?

For example, is the compiler is obliged to throw an error in provably non-uniform cases, where a primitive is misused such as barrier or derivative.
Should the compiler be conservative and only permit provably good cases?

There are many options in the design space, especially since the dynamic behaviour of the shader invocations cannot in general be determined statically. (e.g. the halting problem).

This was discussed but unresolved in the San Diego F2F, notes are at this bookmark: https://docs.google.com/document/d/1tXp8CJ0GQa4TGS_4skRPegzFut9alZkRt4KCP7m7oQk/edit#bookmark=id.940m37e17g4l

cc: @RobinMorisset