Stephen Colebourne wrote:
To say that software should not care and that it is unsupported is .... er .... rather worrying.
Although it is an issue, the DST-vs-STD offsets are implementation details that are neither exposed by the reference API nor exported to zic's output files. Any values they internally have were not intended to be visible when the tzdata entries were written. Of course other implementations are free to process tzdata sources in other ways -- to take an extreme example, implementations could export tzdata comments to their APIs. However, this sort of thing is not part of the reference tz API, and any regression suite based on the reference API shouldn't worry about it.
I'm not sure this project fully appreciates or understands the downstream impacts of changes on systems other than zic.
It's helpful to mention those impacts on this list, if only clarify issues like these in the documentation. Proposed patch attached. This patch doesn't change zic's behavior; it just documents the way zic has always behaved.