When is an implementation allowed/forbidden to flush a command queue?

The specification does list a number of situations in which an implementation is required to flush a command but outside of that it doesn't conclusively state whether flushing a command queue is allowed or forbidden in other API calls or outside of API calls.

See discussion on https://github.com/KhronosGroup/OpenCL-CTS/pull/1012

Start with the discussion in KhronosGroup/OpenCL-CTS pull request 1012 and compare it with the specification's listed command-queue flush requirements. Done means reaching and documenting a clear normative conclusion about whether implementations may or may not flush in other API calls or outside API calls.

Written by the indexing model from the issue text.