Goals

Use Realm to perform basic database operations

Expected Results

App should not encounter any Realm-related crashes

Actual Results

App crashes with the following log:
Terminating app due to uncaught exception 'RLMException', reason: 'ConstIterator copy failed'

Steps to Reproduce

The issue is intermittent. Crash happens when all objects are deleted using

try realm.write {
   realm.deleteAll()
}

and try to perform operations like realm.add(objects, update: update).

Or could be possible it is due to copying the realm object using:

extension Object: DetachableObject {
  func detached() -> Self {
    let detached = type(of: self).init()
    for property in objectSchema.properties {
      guard let value = value(forKey: property.name) else {
        continue
      }
      if let detachable = value as? DetachableObject {
        detached.setValue(detachable.detached(), forKey: property.name)
      } else { // Then it is a primitive
        detached.setValue(value, forKey: property.name)
      }
    }
    return detached
  }
}

Version of Realm and Tooling

ProductName: Mac OS X
ProductVersion: 10.15.5
BuildVersion: 19F101

Xcode version: 11.5
Build version: 11E608c

Cocoapods version: 1.9.3

Realm version: 5.0.2
RealmSwift version: 5.0.2