iOS Crash: com.facebook.react.runtime.JavaScript: EXC_BAD_ACCESS (code=1, address=0x17)

[DavidMarinCalleja]

Description

We are having trouble running a Swift project that uses an XCFramework generated from Rock. The React Native project generated as a Rock project has a native module with Nitro. When launching the project from XCode, it crashes at:

com.facebook.react.runtime.JavaScript: EXC_BAD_ACCESS (code=1, address=0x17)

// File: ReactInstance.cpp
runtime_->unstable_initializeOnJsThread();

Environment

• Platform: iOS
  ├── @babel/core@7.28.5
  ├── @babel/preset-env@7.28.5
  ├── @babel/runtime@7.28.4
  ├── @callstack/react-native-brownfield@2.0.1
  ├── @react-native/babel-preset@0.81.1
  ├── @react-native/eslint-config@0.81.1
  ├── @react-native/metro-config@0.81.1
  ├── @react-native/typescript-config@0.81.1
  ├── @rock-js/platform-ios@0.11.12
  ├── @rock-js/plugin-brownfield-ios@0.11.12
  ├── @rock-js/plugin-metro@0.11.12
  ├── @rock-js/welcome-screen@0.11.12
  ├── @types/react-test-renderer@19.1.0
  ├── @types/react@19.2.7
  ├── babel-jest@29.7.0
  ├── eslint@8.57.1
  ├── jest@29.7.0
  ├── prettier@2.8.8
  ├── react-native-awesome-library@0.0.0 -> ./modules/awesome-library
  ├── react-native-nitro-modules@0.31.10
  ├── react-native@0.81.1
  ├── react-test-renderer@19.1.0
  ├── react@19.1.0
  ├── rock@0.11.12
  └── typescript@5.9.3

Steps taken to create the Rock React Native project

• Create the Rock project npm create rock with this configuration:
  • What platforms do you want to start with? iOS
  • Which bundler do you want to use? Metro
  • Which plugins do you want to use? Brownfield iOS
  • What do you want to use as cache for your remote builds? None
  • Do you want to install dependencies? Yes
• Create a native library npx create-react-native-library@latest awesome-library with this configuration:
  • Do you want to create a local library? Yes
  • Where do you want to create the library? modules/awesome-library
  • What do you want to name the npm package? react-native-awesome-library
  • What type of library do you want to develop? Nitro module
• Install Cocoapods dependencies pod install --project-directory=ios
• Update npm npm install
• Inside the module folder cd modules/awesome-library install Nigrogen npx -y nitrogen .

I modify the code in App.tsx to use the native module with this code:

import React from 'react';
import { SafeAreaView, StyleSheet, Text, View } from 'react-native';
import WelcomeScreen from '@rock-js/welcome-screen';
import { multiply } from 'react-native-awesome-library';

export default function App() {
  const result = multiply(3, 8);

  return (
    <View style={styles.container}>
      <SafeAreaView style={styles.header}>
        <Text style={styles.text}>Result: {result}</Text>
      </SafeAreaView>
      <View style={styles.content}>
        <WelcomeScreen />
      </View>
    </View>
  );
}

// Here there is CSS style not copied in this example

• Generate the XCFramework files with npx rock package:ios --scheme RockProjectDemoReact --configuration Release

Change in the Xcode Project that uses the XCFramework from the previous step

• Once the XCFramework files have been successfully generated, I create a basic iOS project and use drag & drop to add the files to the section: Frameworks, Libraries, and Embedded
• The structure containing the @main tag is created in this init:

        ReactNativeBrownfield.shared.bundle = ReactNativeBundle
        ReactNativeBrownfield.shared.startReactNative()

• The structure shown in the view, modify the content with:

        VStack {
            ReactNativeView(moduleName: "RockProjectDemo")
        }

[DavidMarinCalleja]

I have uploaded a POC to the following repository so that it can be reproduced: https://github.com/DavidMarinCalleja/poc-react-native-rock-project/

I am also attaching a screenshot of the error that occurs when launching the project:

[thymikee]

I haven't tested with Nitro Modules yet, will reach out to our team and get back to you