Seeing the recent SOUL v1release I decided to have a go at making an OWL wrapper.
I had a few concerns, seeing that they use std::vector, exceptions, and other C++ features that add overhead to binary size and execution times. But it seems it's not a big issue, and telling the compiler to use C++14 instead of C++11, plus a few little tricks, was all that was needed to compile the code generated from some of their examples.
But then when I tried running it I noticed two things: firstly the audio does not seem to be processed in any way, and secondly the processing time is extremely low. So I'm probably doing something wrong with how I'm calling the code.
I opened a topic on the SOUL forum, I will report back when I make more progress.
Meanwhile, if anyone would like to experiment I've put my code here, and I've pushed my C++14 changes to the OwlProgram