Function player_checkpoints 

pub unsafe fn player_checkpoints(
    player: *mut IPlayer,
) -> *mut IPlayerCheckpointData

The player’s IPlayerCheckpointData, or null when the component providing it is not loaded.

Found by walking the player’s extension map for PLAYER_CHECKPOINTS_UID — the virtual getExtension does not consult that map. IExtension is IPlayerCheckpointData’s first base, so the extension pointer is the interface pointer.

Safety

player must be a live IPlayer.