Missing test for generator, but definitely some regression tests are required. I suggest implementing the following simple steps.

1. Add ASAN_OPTIONS to generation step, at least ASAN_OPTIONS="detect_stack_use_after_return=1:fast_unwind_on_malloc=0"
2. Change each CI job to have an additional step to build with freshly generated sources.
3. (Optional, arguable) add step to diff the generated_cpp sources with the currently used generated_cpp_XXX to enforce the regular update.

The last one should be done after the fixes in generator for the known non-determinism.