On Mac and iOS, this thorny issue is made even worse by some ancient Darwin design choices. When the process is terminated, the main thread executes static dest

On Mac and iOS, this thorny issue is made even worse by some ancient Darwin design choices. When the process is terminated, the main thread executes static destructors while the other threads are still running. This causes unpredictable exit-time crashes in (typically cross-platform) code that uses static variables with nontrivial destructors. The solution is to always terminate all threads before exiting. This requires a bit of internal infrastructure that's missing from many projects. If a cross-platform library is being used, it may start its own untracked threads. On iOS, app processes only terminate in special circumstances. When this issue yields a crash it's (currently) imperceptible to the user. However, it's still tracked in the crash statistics.