Proguard line number issue

Question

I got a wried issue with the proguard. In my proguard-rules.pro , I already setup keep line number:

# Keep line numbers
-renamesourcefileattribute SourceFile
-keepattributes SourceFile,LineNumberTable

And in my build.gradle , I open the minifyEnable both debug and release :

buildTypes {
        debug {
            minifyEnabled true
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro', 'google-api-client.pro'

            signingConfig signingConfigs.debug

            ndk {
                abiFilters "armeabi-v7a", "arm64-v8a"
            }
        }
        release {
            minifyEnabled true
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro', 'google-api-client.pro'

            signingConfig signingConfigs.release

            ndk {
                abiFilters "armeabi-v7a", "arm64-v8a"
            }
        }
    }

But when I get a crash, the Debug output line number is correct, but the release line number is error. Here is the logs of debug with minifyEnable , the line number is correct:

java.lang.NullPointerException: Attempt to invoke a virtual method on a null object reference
        at com.frontrow.vlog.ui.personalpage.PersonalPageFragment.musicClicked(SourceFile:952) // The line number is the right position at my source code.
        at com.frontrow.vlog.ui.personalpage.PersonalPageFragment_ViewBinding$e.a(SourceFile:244)
        at butterknife.internal.b.onClick(SourceFile:18)

But it's error that the line number is not correct at the release with the minifyEnable :

java.lang.NullPointerException: Attempt to invoke a virtual method on a null object reference
        at com.frontrow.vlog.ui.personalpage.PersonalPageFragment.musicClicked(SourceFile:1) // The line number is error.
        at com.frontrow.vlog.ui.personalpage.PersonalPageFragment_ViewBinding$e.a(SourceFile:1)
        at butterknife.internal.b.onClick(SourceFile:4)

How can I fix this that the release output can take the right line number?

Answer 1

Well, I figure out that is R8 issue. I setup android.enableR8=false in the gradle.properties and the line number is correct. It seems the gradle version large than 3.4.0 it will open the r8 by default.