Calling Sentry.setUser(null) on React Native v0.77.1 causes a crash on iOS in production / release mode

[hrastnik]

@sentry/react-native SDK Version

6.7.0

How does your development environment look like?

System:
  OS: macOS 15.3
  CPU: (12) arm64 Apple M2 Pro
  Memory: 195.33 MB / 16.00 GB
  Shell:
    version: "5.9"
    path: /bin/zsh
Binaries:
  Node:
    version: 22.13.1
    path: ~/.nvm/versions/node/v22.13.1/bin/node
  Yarn:
    version: 1.22.22
    path: ~/.nvm/versions/node/v22.13.1/bin/yarn
  npm:
    version: 11.1.0
    path: ~/.nvm/versions/node/v22.13.1/bin/npm
  Watchman:
    version: 2024.12.02.00
    path: /opt/homebrew/bin/watchman
Managers:
  CocoaPods:
    version: 1.16.2
    path: /var/folders/ht/h1xcpc3x137gqf6d8dn3z9l40000gn/T/frum_74676_1739784191370/bin/pod
SDKs:
  iOS SDK:
    Platforms:
      - DriverKit 24.2
      - iOS 18.2
      - macOS 15.2
      - tvOS 18.2
      - visionOS 2.2
      - watchOS 11.2
  Android SDK: Not Found
IDEs:
  Android Studio: 2024.2 AI-242.23339.11.2421.12483815
  Xcode:
    version: 16.2/16C5032a
    path: /usr/bin/xcodebuild
Languages:
  Java:
    version: 17.0.9
    path: /usr/bin/javac
  Ruby:
    version: 2.7.6
    path: /var/folders/ht/h1xcpc3x137gqf6d8dn3z9l40000gn/T/frum_74676_1739784191370/bin/ruby
npmPackages:
  "@react-native-community/cli":
    installed: 15.1.3
    wanted: 15.1.3
  react:
    installed: 18.3.1
    wanted: 18.3.1
  react-native:
    installed: 0.77.1
    wanted: 0.77.1
  react-native-macos: Not Found
npmGlobalPackages:
  "*react-native*": Not Found
Android:
  hermesEnabled: true
  newArchEnabled: true
iOS:
  hermesEnabled: true
  newArchEnabled: true

Sentry.init()

Sentry.init({
  dsn: 'https://<redacted>.sentry.io/',
});

Steps to Reproduce

1. Create a new RN project with react-native init
2. Run npx @sentry/wizard@latest -i reactNative
3. Build the app in production / release mode for iOS
4. Call Sentry.setUser(null)

This is the code which is enough to reproduce the issue:

import React from 'react';
import {Alert, Button, View} from 'react-native';

import * as Sentry from '@sentry/react-native';

Sentry.init({
  dsn: 'https://<redacted>.sentry.io/',

  // uncomment the line below to enable Spotlight (https://spotlightjs.com)
  // spotlight: __DEV__,
});

export default function App() {
  return (
    <View style={{padding: 64, flex: 1, backgroundColor: 'white'}}>
      <Button
        title="Sentry.setUser(null)"
        onPress={() => {
          Sentry.setUser(null);
          Alert.alert('User has been set to null');
        }}
      />
    </View>
  );
}

Result

App crashes with error:

libc++abi: terminating due to uncaught exception of type facebook::jsi::JSError: Exception in HostFunction: -[NSNull objectForKeyedSubscript:]: unrecognized selector sent to instance 0x1e3a77a80

[krystofwoldrich]

Hi @hrastnik,
thank you for the message,

sadly we are not able to reproduce the crash by calling Sentry.setUser(null);.

Could you share with us the whole stack trace of the crash?

[radko93]

I'm having the same issue on React Native 0.77.1 new arch static linking. I'm calling it in a cleanup of a useEffect. It only crashes in release mode.
None of the stack traces are really helpful.

EXC_BAD_ACCESS:  p@L_ >
Attempted to dereference null pointer.

xxx`main:
    0x104e9b0f0 <+0>:   stp    x24, x23, [sp, #-0x40]!
    0x104e9b0f4 <+4>:   stp    x22, x21, [sp, #0x10]
    0x104e9b0f8 <+8>:   stp    x20, x19, [sp, #0x20]
    0x104e9b0fc <+12>:  stp    x29, x30, [sp, #0x30]
    0x104e9b100 <+16>:  add    x29, sp, #0x30
    0x104e9b104 <+20>:  bl     0x104e9ab58               ; type metadata accessor for xxx.AppDelegate at <compiler-generated>
    0x104e9b108 <+24>:  mov    x19, x0
    0x104e9b10c <+28>:  bl     0x105b7cfe8               ; symbol stub for: static Swift.CommandLine.unsafeArgv.getter : Swift.UnsafeMutablePointer<Swift.Optional<Swift.UnsafeMutablePointer<Swift.Int8>>>
    0x104e9b110 <+32>:  mov    x20, x0
    0x104e9b114 <+36>:  bl     0x105b7cff4               ; symbol stub for: static Swift.CommandLine.argc.getter : Swift.Int32
    0x104e9b118 <+40>:  bl     0x105b7cff4               ; symbol stub for: static Swift.CommandLine.argc.getter : Swift.Int32
    0x104e9b11c <+44>:  mov    x21, x0
    0x104e9b120 <+48>:  mov    x0, x19
    0x104e9b124 <+52>:  bl     0x105b803c0               ; symbol stub for: swift_getObjCClassFromMetadata
    0x104e9b128 <+56>:  bl     0x105b7e5d8               ; symbol stub for: NSStringFromClass
    0x104e9b12c <+60>:  mov    x29, x29
    0x104e9b130 <+64>:  bl     0x105b7fa6c               ; symbol stub for: objc_retainAutoreleasedReturnValue
    0x104e9b134 <+68>:  mov    x19, x0
    0x104e9b138 <+72>:  bl     0x105b7c2ec               ; symbol stub for: static Swift.String._unconditionallyBridgeFromObjectiveC(Swift.Optional<__C.NSString>) -> Swift.String
    0x104e9b13c <+76>:  mov    x22, x0
    0x104e9b140 <+80>:  mov    x23, x1
    0x104e9b144 <+84>:  mov    x0, x19
    0x104e9b148 <+88>:  bl     0x105b7fa3c               ; symbol stub for: objc_release
    0x104e9b14c <+92>:  mov    x0, x21
    0x104e9b150 <+96>:  mov    x1, x20
    0x104e9b154 <+100>: mov    x2, #0x0                  ; =0 
    0x104e9b158 <+104>: mov    x3, #0x0                  ; =0 
    0x104e9b15c <+108>: mov    x4, x22
    0x104e9b160 <+112>: mov    x5, x23
    0x104e9b164 <+116>: bl     0x105b7a51c               ; symbol stub for: UIKit.UIApplicationMain(Swift.Int32, Swift.Optional<Swift.UnsafeMutablePointer<Swift.UnsafeMutablePointer<Swift.Int8>>>, Swift.Optional<Swift.String>, Swift.Optional<Swift.String>) -> Swift.Int32
->  0x104e9b168 <+120>: mov    x19, x0
    0x104e9b16c <+124>: mov    x0, x23
    0x104e9b170 <+128>: bl     0x105b801c8               ; symbol stub for: swift_bridgeObjectRelease
    0x104e9b174 <+132>: mov    x0, x19
    0x104e9b178 <+136>: bl     0x105b7f544               ; symbol stub for: exit

[hrastnik]

@krystofwoldrich The crash only happens in production, in iOS release builds. I can try to isolate a repro case later today.

[krystofwoldrich]

@hrastnik and @radko93 Thank you for the details, I'll try to reproduce it again in Release.

[krystofwoldrich]

I reproduced the crash, and we are investigating it now.

Update:

The issue is in null not being transformed to nil as it does in Debug and older RN versions.

I suspect this change in RN causing it. facebook/react-native#49250

My comment about the unexpected behavior facebook/react-native#49250 (comment)