So I've built a big C++ object that works but now I'm trying to add MSP functionality and it's severely complaining that dsp_free symbol isn't found. It's finding plenty of other C head symbols but not z_dsp_free.

I tried wrapping the header files in an extern "C"{} block but it's still complaining,

Any idea here? I see something about build phases in XCode but it didn't lead anywhere.

Update: for those wondering about anything like this in the future. You can select all build settings, copy and paste into a text file.

This allows you to compare build settings in filemerge.app.

also the project build settings are different than the target build settings

In my case, the build settings didn't link to the correct frameworks in target build settings in other linker flags.