[C++] StructArray : cached boxed fields not thread-safe #22197
Description
The lazy initialization isn't thread-safe (it relies neither on a lock nor on an atomic).
Perhaps we need a more general "cached property" facility to handle these cases.
Reporter: Antoine Pitrou / @pitrou
Assignee: Antoine Pitrou / @pitrou
PRs and other links:
Note: This issue was originally created as ARROW-5775. Please see the migration documentation for further details.