[ERROR:flutter/runtime/dart_vm_initializer.cc(40)] Unhandled Exception: Exception: Failed to load libLiteRtLm.so with RTLD_GLOBAL

[Michel-Samir]

Trying to load litertlm (e.g. gemma3-270m-it-q8.litertlm) using fromAsset (or even fromBundled) in Android

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await FlutterGemma.initialize();
  runApp(const MyApp());
}

class GemmaService {
  InferenceModel? _model;

  Future<void> initModel() async {
    await FlutterGemma.installModel(modelType: ModelType.gemmaIt, fileType: ModelFileType.litertlm).fromAsset('assets/models/gemma3-270m-it-q8.litertlm').install();

    _model = await FlutterGemma.getActiveModel(maxTokens: 1024, preferredBackend: PreferredBackend.cpu);
  }

  Stream<String> askGemmaStream(String prompt) async* {
    if (_model == null) await initModel();

    final chat = await _model!.createChat();
    await chat.addQueryChunk(Message.text(text: prompt, isUser: true));

    // Listen to the async stream
    yield* chat.generateChatResponseAsync().map((response) {
      if (response is TextResponse) {
        return response.token; // Stream each individual token
      } else if (response is ThinkingResponse) {
        return "[Thinking: ${response.content}]";
      }
      return "";
    });
  }

class _ChatScreenState extends State<ChatScreen> {
  final GemmaService _gemma = GemmaService();
  final TextEditingController _controller = TextEditingController();
  String _lastResponse = "";
  bool _isLoading = false;


  void _handleSend() async {
    if (_controller.text.isEmpty) return;

    setState(() {
      _isLoading = true;
      _lastResponse = ""; // Clear previous response
    });

    try {
      final stream = _gemma.askGemmaStream(_controller.text);
      _controller.clear();

      await for (final token in stream) {
        setState(() {
          _lastResponse += token; 
          _isLoading = false; 
        });
      }
    } catch (e) {
      setState(() {
        _lastResponse = "Error: $e";
        _isLoading = false;
      });
    }
  }
}

I added these lines for GPU in AndroidManifest.xml

<application
        android:name="${applicationName}"
        android:icon="@mipmap/ic_launcher">
        <uses-native-library android:name="libOpenCL.so" android:required="false"/>
        <uses-native-library android:name="libOpenCL-car.so" android:required="false"/>
        <uses-native-library android:name="libOpenCL-pixel.so" android:required="false"/>

android\app\build.gradle.kts

android {
    ndkVersion = "28.2.13676358"

    defaultConfig {
            ndk {
                abiFilters.addAll(listOf("arm64-v8a"))
            }
    }
}

Error:

[LiteRtLmFfi] Loading native libraries...
E/flutter ( 906): [ERROR:flutter/runtime/dart_vm_initializer.cc(40)] Unhandled Exception: Exception: Failed to load libLiteRtLm.so with RTLD_GLOBAL
E/flutter ( 906): #0 LiteRtLmFfiClient._ensureBindings (package:flutter_gemma/core/ffi/litert_lm_client.dart:225:9)
E/flutter ( 906): #1 LiteRtLmFfiClient.initialize (package:flutter_gemma/core/ffi/litert_lm_client.dart:286:5)
E/flutter ( 906): #2 FlutterGemmaMobile.createModel (package:flutter_gemma/mobile/flutter_gemma_mobile.dart:379:25)
E/flutter ( 906):
E/flutter ( 906): #3 FlutterGemma.getActiveModel (package:flutter_gemma/core/api/flutter_gemma.dart:257:12)
E/flutter ( 906):
E/flutter ( 906): #4 GemmaService.initModel (package:llm_v2/services/gemma_service.dart:12:14)
E/flutter ( 906):
E/flutter ( 906): #5 GemmaService.askGemmaStream (package:llm_v2/services/gemma_service.dart:36:25)
E/flutter ( 906):
E/flutter ( 906): #6 _ChatScreenState._handleSend (package:llm_v2/screens/chat_screen.dart:46:7)
E/flutter ( 906):

Note:

• I tried preferredBackend: PreferredBackend.cpu or preferredBackend: PreferredBackend.gpu but both didn't work
• I tried running using --enable-experiment=native-assets but didn't work also
• That code works with models with .Task extensions

flutter doctor -v:

Flutter (Channel stable, 3.41.9, on Microsoft Windows [Version 10.0.19045.6466], locale en-US) [5.7s]
    • Flutter version 3.41.9 on channel stable at G:\Flutter_SDK\flutter_windows_3.41.9-stable\flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 00b0c91f06 (10 days ago), 2026-04-29 10:03:19 -0700
    • Engine revision 42d3d75a56
    • Dart version 3.11.5
    • DevTools version 2.54.2
    • Feature flags: enable-web, enable-linux-desktop, enable-macos-desktop, enable-windows-desktop, enable-android,
      enable-ios, cli-animations, enable-native-assets, omit-legacy-version-file, enable-lldb-debugging,
      enable-uiscene-migration

Android toolchain - develop for Android devices (Android SDK version 35.0.0) [251.8s]
    • Android SDK at G:\Android_SDK\SDK2
    • Platform android-36, build-tools 35.0.0
    • ANDROID_HOME = G:\Android_SDK\SDK2
    • Java binary at: C:\Program Files\Java\jdk-21\bin\java
    • Java version Java(TM) SE Runtime Environment (build 21.0.9+7-LTS-338)
    • All Android licenses accepted.

Device Info:

• Manufacturer/Brand: Xiaomi
• Device Model: Mi 9T
• Android Version: Android 10 QKQ1.190825.002
• CPU: Octa-core Max 2.2GHz
• GPU Renderer: Adreno 618
• Mi 9T (mobile) • c7590258 • android-arm64 • Android 10 (API 29)

[DenisovAV]

Hey, looking at the stack trace — Failed to load libLiteRtLm.so with RTLD_GLOBAL at _ensureBindings means the .so isn't getting bundled into the APK at all (the dlopen returns null before any path-resolution magic kicks in). The plugin uses Flutter's Native Assets hook (hook/build.dart) to fetch the native prebuilts from a GitHub release and bundle them at build time.

A few things worth checking on your side:

1. Is the .so actually inside the APK?

   unzip -l build/app/outputs/flutter-apk/app-debug.apk | grep -i litert

   Should show entries like lib/arm64-v8a/libLiteRtLm.so (~14 MB) and a few companions. If that grep is empty — the hook didn't run.

2. Did the hook actually run during build?

   flutter clean
   flutter pub get
   flutter build apk --debug 2>&1 | grep -iE 'flutter_gemma|hook|native_assets|litert'

   You should see lines like flutter_gemma: Downloaded ... or flutter_gemma: Native libs cached to .... If you see nothing, the hook hasn't been wired up — most often that's because of an older Flutter version. Native Assets need Flutter ≥ 3.24 and Dart SDK ≥ 3.6.0 (your 3.41.9 + Dart 3.11.5 is well above that, so it should be fine — but worth sanity-checking the actual versions used by your build, not what's installed elsewhere).

3. Firewall/proxy on the build machine? The hook fetches from github.com/DenisovAV/flutter_gemma/releases/download/native-v0.11.0-b/.... If that's blocked, the hook fails silently in some Flutter versions. Try running:

   curl -I https://github.com/DenisovAV/flutter_gemma/releases/download/native-v0.11.0-b/android_arm64.tar.gz

   from the same machine.

4. Latest plugin? Mind upgrading to flutter_gemma: ^0.15.2 (just published) and try again? The hook got a bunch of fixes between 0.14.x and 0.15.2 (cache busting, marker files for stale invalidation). The error you posted is from litert_lm_client.dart:225 which is the pre-0.15.x file layout, so it looks like you're on an older version.

If after all that the .so is in the APK but still fails to load on the device, that's a different story — could be a libc / Adreno 618 driver edge case. Let me know what the APK inspection turns up and we'll go from there 🙏

[Michel-Samir]

Thanks for your reply.
I'm sorry to say that the issue is still not resolved for me.
First of all, I performed all these checks on Windows 10.

Point 3:

I'm not sure whether this is the correct URI to fetch from, as you mentioned: https://github.com/DenisovAV/flutter_gemma/releases/download/native-v0.11.0-b/android_arm64.tar.gz

However, it did not work for me. Instead, I used https://github.com/DenisovAV/flutter_gemma/releases/download/native-v0.11.0-b/litertlm-android_arm64.tar.gz, as referenced in hook/build.dart

 
And it was downloaded successfully on the same machine from which I ran flutter build apk --debug.

 
Note: I used curl -L -O instead of curl -I, as curl -I did not work for me and returned HTTP/2 302.
 

Point 2:

First, I already ran flutter clean and flutter pub get. When running flutter build apk --debug, I can clearly see these lines

 

I also checked and found that the native libraries are cached at:

 

Point 1:

I checked, and yes, the .so is actually inside the APK.

 

Point 4:

Sure, before doing all these checks, I upgraded the plugin to the latest version: flutter_gemma: ^0.15.2

 
When running the APK, I still get the same error: Exception: Failed to load libLiteRtLm.so with RTLD_GLOBAL

 

Thank you for your time and consideration. I look forward to your reply.

[DenisovAV]

Thanks for the detailed validation — that confirmed the .so is in the APK and dlopen() itself is failing. Reproduced today on an Android 10 / arm64 emulator (same API level as your Mi 9T) and got the real dlerror() underneath our generic message:

cannot locate symbol "pthread_cond_clockwait" referenced by libLiteRtLm.so

That function was added to Bionic in Android 11 (API 30). The upstream libLiteRtLm.so is built against API 30+ libc, so it can't load on Android 10 at all. This isn't fixable on our side — only an upstream rebuild against API 29 would address it.

Two options for you:

1. Bump minSdkVersion to 30 in android/app/build.gradle if you can drop Android 10 support. .litertlm will work everywhere else.
2. Stick with API 29 — use a MediaPipe .task model instead of .litertlm (e.g. gemma-3n-E2B-it-int4.task). The MediaPipe engine works on API 21+ and the plugin routes to it automatically based on the file extension.

I'll improve the error message in a follow-up so it points here instead of the cryptic dlopen string. Sorry for the runaround.

[Michel-Samir]

Thanks for the quick update! I tested it on an Android 14 phone and it works perfectly.

It would be great to add these API requirements to the README.md as well, just so other developers can see it right when setting up.

Thanks again for your help!