Flutter build Proguard configuration rule does not match anything

Question

I am running a Flutter release build and am getting warnings Proguard configuration rule does not match anything. See below for a full list.

Should this be raised to Flutter GitHub issues or am I doing something wrong?

My build command is: flutter build appbundle --release --obfuscate --split-debug-info=./build/symbols (same happens if I remove --obfuscate flag)

My project does not contain any proguard-rules.pro files.

My app/build.gradle config is:

buildTypes {
        release {
            signingConfig signingConfigs.release

            ndk {
                abiFilters 'arm64-v8a', 'armeabi-v7a', 'x86_64'  //, 'x86'
            }

            minifyEnabled true
            shrinkResources true
           
        }
    }
}

I am using the following build tools and settings:

• Gradle 8.4
• Gradle plugin 8.1.2
• Kotlin 1.9.10
• Java 17
• ndk Version 26.0.1909125
• compileSdkVersion 34
• minSdkVersion 28
• targetSdkVersion 34

Full list of warnings

Info: Proguard configuration rule does not match anything: `-keepclassmembers class j$.util.concurrent.ConcurrentHashMap$TreeBin {
  int lockState;
}`
Info: Proguard configuration rule does not match anything: `-keepclassmembers class j$.util.concurrent.ConcurrentHashMap {
  int sizeCtl;
  int transferIndex;
  long baseCount;
  int cellsBusy;
}`
Info: Proguard configuration rule does not match anything: `-keepclassmembers class j$.util.concurrent.ConcurrentHashMap$CounterCell {
  long value;
}`
Info: Proguard configuration rule does not match anything: `-keepclassmembers enum * {
  public static **[] values();
  public static ** valueOf(java.lang.String);
  public static final synthetic <fields>;
}`
Info: Proguard configuration rule does not match anything: `-keepclassmembers class j$.util.IntSummaryStatistics {
  long count;
  long sum;
  int min;
  int max;
}`
Info: Proguard configuration rule does not match anything: `-keepclassmembers class j$.util.LongSummaryStatistics {
  long count;
  long sum;
  long min;
  long max;
}`
Info: Proguard configuration rule does not match anything: `-keepclassmembers class j$.util.DoubleSummaryStatistics {
  long count;
  double sum;
  double min;
  double max;
}`