There's a particular line that I don't understand in the Arrow C++ library and which is giving me trouble:
https://github.com/apache/arrow/blob/main/cpp/src/arrow/compute/kernels/scalar_cast_nested.cc#L196-L199 This seems like a strange constraint. The spec says that "Whether the field is semantically nullable [..] has no bearing on the array’s physical layout" (https://arrow.apache.org/docs/format/Columnar.html#schema-message) so it seems like this should always be safe, right? https://github.com/apache/arrow/issues/33592 is an example of a Github issue this causes.
