Alamofire causes crash on iPhone 5 - swift

Question

I currently give some users access to my app via TestFlight so that they can test it. On every iPhone the App works perfectly without any problems but on the iPhone 5 the app crashes every time. In the xCode simulator everything works properly but not on a real device.
It looks like Alamofire causes the crash. The problem is in Alamofire>Source>Features>ResponseSerialization.swift>response(queue:completionHandler:)
Here is the code from the function:
/// Adds a handler to be called once the request has finished.
///
/// - parameter queue: The queue on which the completion handler is dispatched.
/// - parameter completionHandler: The code to be executed once the request has finished.
///
/// - returns: The request.
#discardableResult
public func response(queue: DispatchQueue? = nil, completionHandler: #escaping (DefaultDataResponse) -> Void) -> Self {
delegate.queue.addOperation {
(queue ?? DispatchQueue.main).async {
var dataResponse = DefaultDataResponse(
request: self.request,
response: self.response,
data: self.delegate.data,
error: self.delegate.error
)
dataResponse.add(self.delegate.metrics)
completionHandler(dataResponse)
}
}
return self
}
completionHandler(dataResponse) looks like it is the problem.
Below there is also a screenshot from xCode
Is this a Alamofire related problem? Because on every other device (5s, 6 Plus, 7 Plus, SE and 7) it works without any problems. The crash occur when the iPhone is connected to WiFi and when it uses the mobile network.
Thanks for any tips!
EDIT:
This should be the code section that is called when starting the application:
Alamofire.request("https://app.site.tld/mobile/ios", parameters: parameters).response { response in
print("Request: \(response.request)")
print("Response: \(response.response)")
print("Error: \(response.data)")
if response.response != nil{
if let data = response.data, let utf8Text = String(data: data, encoding: .utf8) {
print("Data: \(utf8Text)")
let weatherDataArr = utf8Text.components(separatedBy: "~")
guard let hash = String(weatherDataArr[0]) else {
completion(nil)
return
}
do {
//working with received data.
//let currData: wData = try wData(hash: hash, ....)
completion(currData)
} catch {
print("error creating Object: \(error)")
completion(nil)
}
}
else {
completion(nil)
}
}else {
completion(nil)
}
}
Just found a warning in xCode that says:
'catch' block is unreachable because no errors are thrown in 'do' block

Answer 1

First simplify to remove clutter
Alamofire.request("https://app.site.tld/mobile/ios", parameters: parameters).response { response in
print("Request: \(response.request)")
print("Response: \(response.response)")
print("Error: \(response.data)")
var result: wData? = nil
defer { completion(result) }
guard response.response != nil else { return }
if let data = response.data, let utf8Text = String(data: data, encoding: .utf8) {
print("Data: \(utf8Text)")
let weatherDataArr = utf8Text.components(separatedBy: "~")
guard let hash = String(weatherDataArr[0]) else { return }
//working with received data.
//let currData: wData = try wData(hash: hash, ....)
result = currData
}
}
Then we can ask ourselves
How are you 100% sure there are elements in weatherDataArr? If not, use guard let hash = weatherDataArr.first else { return }
What happens under //working with received data.?