Bug report: code generation error for multi-threading Simulink model

Problem description:

I tried to generated C++ code from an adapted version of Assigning Tasks to Cores for Multicore Programming - MATLAB & Simulink (mathworks.com) example, the code generation fails with the following error message:

Reproduction steps:

1. extract the attachment AssigningTaskstoCoresforMulticoreProgramming.zip
2. unpack the project files
3. send Ctrl+B to slexMulticoreExample.slx