How to remote-debug Android native code with RustRover (lldb-server gdbserver mode)

1. Start lldb-server on Android (gdbserver mode)

1. Make sure your app is installed and running on the device/emulator.

2. Find the app PID (example):

   adb shell ps | grep com.example.app
   # note the PID, e.g. 27072
   

3. Use a helper script like this (adapt paths and APP/ABI/PID):

   #!/usr/bin/env bash
   export APP=com.example.app
   export ABI=i386
   export PID=27072   # replace with real PID
   
   function start_adb() {
     # Push tools (adjust NDK path if needed)
     adb push "$HOME/Android/Sdk/ndk/28.2.13676358/toolchains/llvm/prebuilt/linux-x86_64/lib/clang/19/lib/linux/$ABI"* /data/local/tmp/tools
   
     # Copy lldb-server into app data
     adb shell "run-as ${APP} cp /data/local/tmp/lldb-server /data/data/${APP}/lldb-server"
   
     # Forward port 5039 from host to device
     adb forward tcp:5039 tcp:5039
   
     # IMPORTANT: use gdbserver mode (NOT platform mode)
     adb shell "run-as ${APP} /data/data/${APP}/lldb-server gdbserver *:5039 --attach ${PID}"
   }
   
   start_adb
   

4. Check that the script completes without error and that your app process remains running (now under lldb-server control).

Key rule: do not use lldb-server platform --listen ... --server; always use lldb-server gdbserver ....

2. Create a Remote Debug configuration in RustRover

1. In RustRover, go to Run | Edit Configurations….
2. Click + → choose Remote Debug.
3. Select LLDB as the debugger (bundled LLDB is usually fine).

Fill in:

• process connect url:

  connect://localhost:5039
  

• Symbol file: local path to the debug build of the binary/library running on the device (for example: .../target/i686-linux-android/debug/libmy_native.so).

Optionally (recommended in cross‑platform setups):

• Sysroot: local path with target libraries and debug symbols (from your NDK / sysroot).
• Path mappings:
  • Remote: /data/data/com.example.app/lib/ → Local: /path/to/project/target/i686-linux-android/debug/
  • Add others as needed so source paths line up.

3. Run the debug session

1. On Android: run your start_adb script again whenever you restart the app or device.
2. In RustRover:
   • Open the project, place breakpoints in your native code.
   • Select the Remote Debug configuration.
   • Click Debug.

If everything is configured correctly, RustRover will:

• connect to lldb-server gdbserver on the device,
• stop at the entry point or your first breakpoint,
• let you step through and inspect variables as if the code were local.

4. Quick troubleshooting checklist

If you see:

• "No stop reply packet was received" → Most often means you started lldb-server in platform mode instead of gdbserver mode. Re‑check the script: it must say lldb-server gdbserver ....
• Breakpoints never hit
  • Ensure the Symbol file points to the correct debug binary (not stripped).
  • Verify Path mappings match remote vs local paths.
  • Make sure you rebuilt and re‑deployed the same binary that RustRover is using for symbols.
• Connection fails immediately
  • Confirm adb forward tcp:5039 tcp:5039 is in effect.
  • Verify no firewall or other process is blocking port 5039.
  • Make sure the device is visible via adb devices.

Related articles

[Guide]: Setup Remote-debugging Android native code with RustRover + lldb-server (gdbserver mode) Standalone