My Android app only crashes when not debuggable?

Question

I have an Android app that works fine in debug mode but started giving issues in release mode. It crashes while binding items to a recyclerview.

Initially I thought this would be a proguard issue, but after enabling proguard for debug mode it became clear that only the release version had this issue. Just to try it out, I set the release version as debuggable true and the problem is gone.

Does anyone have an idea what could cause a crash only if the apk is not debuggable? Or any way to debug this and see what exactly is going wrong?

These are my buildtypes:

buildTypes {
    debug {
        multiDexEnabled true
        shrinkResources true
        minifyEnabled true
        useProguard true
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }
    release {
        multiDexEnabled true
        shrinkResources true
        minifyEnabled true
        useProguard true
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }
}

So, if I add debuggable true to release, the release version works. If I add debuggable false to debug, the debug version stops working...

Logcat:

E/AndroidRuntime: FATAL EXCEPTION: main
Process: __, PID: _
a.a
    at ___.overview.dashboard.m.a(Unknown Source)
    at ___.overview.dashboard.c.a(Unknown Source)
    at android.support.v7.widget.RecyclerView$a.a(Unknown Source)
    at android.support.v7.widget.RecyclerView$a.b(Unknown Source)
    at android.support.v7.widget.RecyclerView$p.a(Unknown Source)
    at android.support.v7.widget.RecyclerView$p.a(Unknown Source)
    at android.support.v7.widget.RecyclerView$p.a(Unknown Source)
    at android.support.v7.widget.RecyclerView$p.c(Unknown Source)
    at android.support.v7.widget.LinearLayoutManager$c.a(Unknown Source)
    at android.support.v7.widget.LinearLayoutManager.a(Unknown Source)
    at android.support.v7.widget.LinearLayoutManager.a(Unknown Source)
    at android.support.v7.widget.LinearLayoutManager.c(Unknown Source)
    at android.support.v7.widget.RecyclerView.N(Unknown Source)
    at android.support.v7.widget.RecyclerView.q(Unknown Source)
    at android.support.v7.widget.RecyclerView.onLayout(Unknown Source)
    at android.view.View.layout(View.java:18798)
    at android.view.ViewGroup.layout(ViewGroup.java:5951)
    at android.support.constraint.ConstraintLayout.onLayout(Unknown Source)
    at android.view.View.layout(View.java:18798)
    at android.view.ViewGroup.layout(ViewGroup.java:5951)
    at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
    at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
    at android.view.View.layout(View.java:18798)
    at android.view.ViewGroup.layout(ViewGroup.java:5951)
    at android.support.constraint.ConstraintLayout.onLayout(Unknown Source)
    at android.view.View.layout(View.java:18798)
    at android.view.ViewGroup.layout(ViewGroup.java:5951)
    at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
    at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
    at android.view.View.layout(View.java:18798)
    at android.view.ViewGroup.layout(ViewGroup.java:5951)
    at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1741)
    at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1585)
    at android.widget.LinearLayout.onLayout(LinearLayout.java:1494)
    at android.view.View.layout(View.java:18798)
    at android.view.ViewGroup.layout(ViewGroup.java:5951)
    at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
    at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
    at android.view.View.layout(View.java:18798)
    at android.view.ViewGroup.layout(ViewGroup.java:5951)
    at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1741)
    at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1585)
    at android.widget.LinearLayout.onLayout(LinearLayout.java:1494)
    at android.view.View.layout(View.java:18798)
    at android.view.ViewGroup.layout(ViewGroup.java:5951)
    at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
    at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
    at com.android.internal.policy.DecorView.onLayout(DecorView.java:887)
    at android.view.View.layout(View.java:18798)
    at android.view.ViewGroup.layout(ViewGroup.java:5951)
    at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2648)
    at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2364)
    at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1515)
    at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:7091)
    at android.view.Choreographer$CallbackRecord.run(Choreographer.java:927)
    at android.view.Choreographer.doCallbacks(Choreographer.java:702)
    at android.view.Choreographer.doFrame(Choreographer.java:638)
    at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:913)
    at android.os.Handler.handleCallback(Handler.java:751)
    at android.os.Handler.dispatchMessage(Handler.java:95)
    at android.os.Looper.loop(Looper.java:154)
    at android.app.ActivityThread.main(ActivityThread.java:6682)
    at java.lang.reflect.Method.invoke(Native Method)

Answer 1

If you are using C overloaded functions, don't!

I.E Class A

ofAndroidInit(){ 
  // will only work with debugging = false
}

Class B main.cpp

ofAndroidInit() {
 // will work with debugging = true
}

Answer 2

For me the issue was that I was testing the release version and disabled Crashlytics for that to not track my activity. When "debuggable" was set to true is worked fine, but once set to false I was receiving an instant crash on app start. So basically I forgot to turn on the Crashlytics and was getting some internal error from it.

Answer 3

as @laalto said, there's a stacktrace that can be helpful

Putting this in my proguard file:

-keepattributes SourceFile,LineNumberTable

helped me find where the error was. This shows you the original classnames and linenumbers in the stacktrace. I'm still not sure why the error doesn't occur for debug mode, but at least I was able to solve it. Thanks again!