Warning causing android build to fail

Question

I have native android code that i bundle with my app. This has always been working for many months. But today, the same code is failing with warnings. I think the last successful build was two days ago:

--    
Note: there were 5 references to unknown classes.
          You should check your configuration for typos.
          (http://proguard.sourceforge.net/manual/troubleshooting.html#unknownclass)
    Note: there were 1927 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 2 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)
    Note: there were 4 class casts of dynamically created class instances.
          You might consider explicitly keeping the mentioned classes and/or
          their implementations (using '-keep').
          (http://proguard.sourceforge.net/manual/troubleshooting.html#dynamicalclasscast)
    Warning: there were 23 unresolved references to program class members.
             Your input classes appear to be inconsistent.
             You may need to recompile the code.
             (http://proguard.sourceforge.net/manual/troubleshooting.html#unresolvedprogramclassmember)
    Exception while processing task 
    java.io.IOException: Please correct the above warnings first.
        at proguard.Initializer.execute(Initializer.java:473)
        at proguard.ProGuard.initialize(ProGuard.java:233)
        at proguard.ProGuard.execute(ProGuard.java:98)
        at proguard.gradle.ProGuardTask.proguard(ProGuardTask.java:1074)
        at com.android.build.gradle.tasks.AndroidProGuardTask.doMinification(AndroidProGuardTask.java:139)
        at com.android.build.gradle.tasks.AndroidProGuardTask$1.run(AndroidProGuardTask.java:115)
        at com.android.builder.tasks.Job.runTask(Job.java:48)
        at com.android.build.gradle.tasks.SimpleWorkQueue$EmptyThreadContext.runTask(SimpleWorkQueue.java:41)
        at com.android.builder.tasks.WorkQueue.run(WorkQueue.java:227)
        at java.lang.Thread.run(Thread.java:745)
    :proguardRelease (Thread[Daemon worker,5,main]) completed. Took 6.197 secs.
    :dexRelease (Thread[Daemon worker,5,main]) started.
    :dexRelease
    Executing task ':dexRelease' (up-to-date check took 0.058 secs) due to:
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Answer 1

So, i have found out, proguard task will halt execution if there are warnings. While searching the net reveals various ways of dealing with these,the bottom line is to make sure you fix the warnings.