Then, you should be able to merge the databases, too. I was able to make it work, but only for a very simple script.
From a high level, how did you go about doing it? Is it just concatenating some or all of the text files in the cover_db directory? Or do you have to do a manual interleave of data within each file? Or worse, a manual interleave-and-add for counts for certain lines of code? Is it just a subset of files that you have to merge?
Sorry, since I've never looked into merging them before, or really even at the raw data -- I always just look at the HTML report at the end -- I wouldn't know where to start for the merge. Given the original question, it wouldn't surprise me if the OP was in the same boat as I am. So hints as to how to get started with the merge would be nice. (I am bookmarking this thread, since I think some of my repos might get better coverage numbers if I am able to eventually merge the linux and windows results; I'm reasonably confident that between the CI systems, I have full coverage, but being able to prove it would feel nice.)