Error when building Android: ':app:minifyReleaseWithR8'

[burekas7]

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Which mobile framework are you using?

Flutter (Dart)

Steps to reproduce

Hi,

I recently updated the Flutter version to 3.24.2
And when I try to build a version but I get an android build failure:

ERROR: Missing classes detected while running R8. Please add the missing classes or apply additional keep rules that are generated in /Users/builder/clone/build/app/outputs/mapping/release/missing_rules.txt.
ERROR: R8: Missing class com.google.j2objc.annotations.RetainedWith (referenced from: com.google.common.collect.ImmutableSet com.google.common.collect.ImmutableMap.entrySet and 3 other contexts)

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:minifyReleaseWithR8'.
> A failure occurred while executing com.android.build.gradle.internal.tasks.R8Task$R8Runnable
   > Compilation failed to complete

On debug, everything is fine and working.

I tried putting # android.enableR8=true in the comment
(as it appears in another application since it is being built properly, and it still didn't help)

What could be the reason?

Build ID:
66e83d141a04c8ef79f8e6d0

[burekas7]

Solved:
I added this file: android/app/proguard-rules.pro

And added the needed rules according to the missing_rules.txt file.