Stuck on an issue?

Lightrun Answers was designed to reduce the constant googling that comes with debugging 3rd party libraries. It collects links to all the places you might be looking at while hunting down a tough bug.

And, if you’re still stuck at the end, we’re happy to hop on a call to see how we can help out.

Error when assembling Android release with proguard

See original GitHub issue

Description

After creating a new React Native project, enabling proguard per these instructions, and building a release Android build I get the following error:

Note: there were 2 references to unknown classes.
      You should check your configuration for typos.
      (http://proguard.sourceforge.net/manual/troubleshooting.html#unknownclass)
Note: there were 654 unkept descriptor classes in kept class members.
      You should consider explicitly keeping the mentioned classes
      (using '-keep').
      (http://proguard.sourceforge.net/manual/troubleshooting.html#descriptorclass)
Note: there were 7 unresolved dynamic references to classes or interfaces.
      You should check if you need to specify additional program jars.
      (http://proguard.sourceforge.net/manual/troubleshooting.html#dynamicalclass)
Warning: there were 1 unresolved references to library class members.
         You probably need to update the library versions.
         (http://proguard.sourceforge.net/manual/troubleshooting.html#unresolvedlibraryclassmember)
Warning: Exception while processing task java.io.IOException: Please correct the above warnings first.
:app:transformClassesAndResourcesWithProguardForRelease FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:transformClassesAndResourcesWithProguardForRelease'.
> Job failed, see logs for details

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

BUILD FAILED

The specific warning in the output is:

Warning: com.facebook.fbui.textlayoutbuilder.proxy.StaticLayoutProxy: can't find referenced method 'StaticLayout(java.lang.CharSequence,int,int,android.text.TextPaint,int,android.text.Layout$Alignment,android.text.TextDirectionHeuristic,float,float,boolean,android.text.TextUtils$TruncateAt,int,int)' in library class android.text.StaticLayout

Reproduction

react-native init --version="0.42.0" myapp
cd myapp/android
sed -i -e 's/enableProguardInReleaseBuilds = false/enableProguardInReleaseBuilds = true/g' app/build.gradle
./gradlew --offline assembleRelease
Notice the error above