That is, the hint was not included when force_error=true, which does not seem quite necessary. Based on off-list discussion with Pavel this was unnecessary, so the hint is now included always.
2) The comment in plpgsql.h still mentioned "compile-time" checks only, but the new checks are run-time checks. So tweaked accordingly.
3) A couple of minor formatting / code style changes.
Many thanks
Pavel
regards -- Tomas Vondra http://www.2ndQuadrant.com PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services