How do you debug Rust code on Android?

[coder0xff]

Hi, I'm using flutter_rust_bridge to work on an application that I'm primarily testing on Android, and using Visual Studio Code for debugging the Flutter parts. I'm wondering if there's a way to debug the Rust parts invoked by Flutter in the same dev environment. Barring that, is there a way to debug the rust code in any of the other environments, e.g. Linux or Windows, Android Studio or GDB? Thanks for any advice.

[fzyzcjy]

Looking forward others to answer this, since I myself do not use debug (but use logging) when I want to see bugs in my code.

[coder0xff]

I tried using println! but nothing appeared, so I also tried the log+logsys crates to log to the system log on Android, but that was crashing due to the location not existing in the filesystem. Do you have a trick for Android log statements?

[fzyzcjy]

https://cjycode.com/flutter_rust_bridge/feature/logging.html

[coder0xff]

Thanks, I'll give it a try.

[tmpfs]

This worked for me:

[target.'cfg(target_os="android")'.dependencies]
android_logger = "0.11.1"

Along with the usual log crate and then just log::info!() etc. Now I just need to figure out how to get rid of all the noise the android logs by default!

[coder0xff]

Not Android, but I found that for the Linux target that (after running sudo sysctl kernel.yama.ptrace_scope=0) I could go to the VS Code command menu with Ctrl+P > LLDB: Attach to Process... and attach to the process, giving me working breakpoints in Dart and Rust simultaneously.

Android Studio also has the ability to attach to running processes on a device, so I opened the android folder and gave it a try. It was able to attach to the JVM debugger, but when I tried to force native debugging it would show

If I were to hazard a guess, it doesn't know how to find the Rust code.