React-native: Deadlock/Freeze with native modules and Remote debug 0.26.0

[olofd]

Hi!
I have a fairly big project in react native where I after updating to 0.26.0 get a deadlock if I enable the Remote debugging option (With JSC the app runs great, as on 0.25.1). I've boiled this down to me having 2 custom native modules that implement RCTViewManager. If I remove either one of them (just uncomment RCT_EXPORT_MODULE()), the deadlock goes away and the app launches.

The deadlock presents it self in that the app becomes unresponsive and locked.
I think that this change might have something to do with this issue:

https://github.com/facebook/react-native/commit/9547a98a685cb9121c31cf19cd17f4ed0feeac2e

Let me know if I can provide more info.
Of course I've clear cache, reset simulator, watchman watch-del-all and derived data rm rf nodemodules etc.

Repro of the problem:
Build. Launch debugging. (Might work once), rebuild the project with debugging enabled in the simulator.
Should freeze.
https://github.com/olofd/Test-react-native-26

The repo has two native modules that return a UIView. Test and Test2

[marcshilling]

Yikes! How did this one slip through? When this occurs I literally have to delete the app from the simulator in order to get up and running again. A simple rebuild always results in a frozen blank white screen.

I'm not positive that it's related to Native Modules though @olofd...unless I'm forgetting one, I completely removed all Native Modules from my project and still can't debug in Chrome. Or is excluding the Native Module library file from the build phase not enough?

[powerc9000]

The only thing I have been able to gather about this is. If you run the app through Xcode instead of react-native run-ios in the "All Output" section of Xcode you see this:

2016-05-19 13:36:34.303 [error][tid:com.facebook.react.RCTBridgeQueue][RCTWebSocketExecutor.m:71] Connection to http://localhost:8081/debugger-proxy?role=client timed out. Are you running node proxy? If you are running on the device, check if you have the right IP address in `RCTWebSocketExecutor.m`.

Now I know that the simulator can reach that address in Safari and if I have debugging off it grabs the bundle just fine and runs with no deadlock.

[olofd]

@marcshilling Yes. I have to remove the app as well when this occurs. Glad it does not only happen on my two machines then. It's really weird and I'm not 100% sure that my theory of two modules vs. one module is correct. But I know that messing with/uncommenting RCT_EXPORT_MODULE() makes a difference.

FYI. I know that this was present in 0.26.0-rc as well. I tried that RC about a week ago, ran into this issue. and reverted back to 0.25.1. Had no time to investigate then.

[liorshalev01]

The same problem is also here after updating to 0.26.

[halilb]

I'm experiencing the same after 0.26 update.

[ncnlinh]

Ditto. Crying inside after all the effort spent to upgrade to 0.26

[terran42]

+1, same problem.

I replaced RCTBatchedBridge.m with the version in 0.25.1 and it's now working. Didn't dig in though.

https://github.com/facebook/react-native/blob/0.25-stable/React/Base/RCTBatchedBridge.m

[xu6148152]

@origsun
We did this too.

[sunnylqm]

No FB members yet? Maybe we need a little poking?... @mkonicek @nicklockwood

[Kerumen]

Got the same issue here. Very frustrating..

[formatlos]

same issue for me ... replacing RCTBatchedBridge.m did work for now

[ivpusic]

same here

[mkonicek]

Thanks for the ping. Is this iOS-only? There was a bug in remote debugging but I believe that was only on Android and got fixed in 0.26.1, @grabbou am I right?

[formatlos]

I'm actually on 0.26.1 on iOS

[jaygarcia]

upgrading to RN 27-rc fixed this for me.

TBH, i thought i was going mad.

[grabbou]

@mkonicek the debugger issue was 0.27 specific problem and is to be released today / tomorrow (fixed already in master).

[ivpusic]

@jaygarcia 0.27 does not work with react native router flux which many people are using, so this means 0.26 is not very useable until this is fixed

[xu6148152]

@mkonicek @grabbou Android has the same problem 0.26.1, I scroll back to 0.26, and it works well.

[mkonicek]

@grabbou What was the fix please? Curious to understand how we can prevent it breaking in the future. More tests?

[Elyx0]

@mkonicek Replace RCTBatchedBridge.m with the version in 0.25.1
https://github.com/facebook/react-native/blob/0.25-stable/React/Base/RCTBatchedBridge.m

Worked for me

[grabbou]

@mkonicek for the debugger? It's unfortunately still present https://github.com/facebook/react-native/issues/7659#issuecomment-221440732

[Roconda]

+1 this is a very annoying issue.

[mdutkin]

@Elyx0 it also worked for me! thnx!

im on RN 0.26.2 running iOS app

[marcshilling]

This seems to be fixed in 0.27.0

[mkonicek]

Replace RCTBatchedBridge.m with the version in 0.25.1
https://github.com/facebook/react-native/blob/0.25-stable/React/Base/RCTBatchedBridge.m

Just read this again. It's a pretty bad one, sorry! Seems like a regression introduced in 0.26.

Is anyone still seeing this on 0.27, or 0.28.0-rc.0?

[Kenny1366]

i am using the latest version 0.29. it seems that this issue still there, what do i do? please help. thanks

[Elyx0]

Updated to 0.29, no deadlock but no debugger anymore either And I get [RCTEventEmitter.m:52] SendingwebsocketFailedwith no listeners registered. in the console. Version from .25 of RCTBridge is sadly incompatible. Poke @mkonicek

[RD1991]

I got following message as well when i replaced RCTBridge file with 0.25 version in 0.29 :
Class RCTEventEmitter was not exported. Did you forget to use RCT_EXPORT_MODULE()?
[RCTEventEmitter.m:52] Sending websocketFailed with no listeners registered.

[ivpusic]

0.30 everything works fine for me

[mkonicek]

Hi there! This issue is being closed because it has been inactive for a while.

But don't worry, it will live on with ProductPains! Check out its new home: https://productpains.com/post/react-native/deadlockfreeze-with-native-modules-and-remote-debug-0260

Product Pains has been very useful in highlighting the top bugs and feature requests:
https://productpains.com/product/react-native?tab=top

Also, if this issue is a bug, please consider sending a pull request with a fix.