First attempt at a VST3/AU plugin fails to build in Xcode. VST3 only succeeds

macOS 10.14.6
JUCE 5.4.5
XCode 11.1

My first encounter with JUCE was successful. Following the tutorial, I managed to create a test Audio application and was able to build and test in XCode. So far, so good!

Buoyed with this success, I then tried to follow the instructions for creating an audio plugin. I set the filename and then checked that the VST3 and AU checkboxes were selected as well as the MIDI inputs and outputs settings.

When I hit the build button within XCode, the build failed with the following error…

However, when I repeated the process with only the VST3 checkbox enabled, my XCode build succeeded.

For my own personal needs, this isn’t a problem because my main DAW is Bitwig which doesn’t support AUs, but I may find that am not too bad at this plugin malarkey in the future and will obviously want to support AUs.

My question is, therefore: Is my build failure to be expected? Am I being prematurely ambitious, only to find out in the next tutorial exactly what I am doing wrong? Forgive me if this is the case, only I am very keen to make progress with JUCE having been inspired this evening by watching a video of the great Steve Duda, who wishes that he could have used JUCE when developing Serum, apparently!

It’s ironic that, after 30 years of avoiding C++ as a programming language as a professional developer, I should now be willing to dip my toes into C++, albeit with a great deal of hand-holding by JUCE. It’s a shame that my current favourite Golang isn’t supported, but on the plus side, if all goes well, I will be finally able to call myself a “proper” developer :wink:

UPDATE: I tried again selecting AU by itself as the plugin type, but that failed as well. I’ve just discovered that others have had this issue as well: AU on XCode 10: ResMerger Error. I’m not in a position to fix this myself, so I’ll just have to wait till someone else or JUCE fix it!

UPDATE2: I then tried the AU3 option. This did succeed in building within XCode. However, although the AU3 component showed up with Auganizer, it didn’t appear visible in Ableton Live 10. Whether that’s because it’s an AU3 as opposed to an AU I don’t know…