The bug

The campfire crafting recipe requires three logs. Regular logs, stripped logs, as well as regular and stripped bark (AKA "wood") all work fine, but only certain combinations thereof. For example, oak and birch logs can be mixed, but stripped oak and birch logs cannot.

The exact incompatibilities are described here:

1. Oak Log, Spruce Log, Birch Log, and Jungle Log are compatible with each other and nothing else.
2. Acacia Log and Dark Oak Log are compatible with each other and nothing else.
3. Each stripped log is incompatible with everything other than itself.
4. Wood/bark (stripped and unstripped) is compatible with any other kind of wood/bark, but not any kind of log. [* note]

Examples

All combinations of logs/wood should be compatible

* This cannot be used in the smoker crafting recipe at all. Debatable whether this is a separate bug.