In my android project, I'm using a library and to keep its classes I have the following rules in the proguard config file:
-keep class com.folioreader.** { *; }
-keep class org.readium.r2.shared.** { *; }

The app was working fine, till I upgrade to AS 4.0 and AS 4.1. Now the new apk generated with the same library and the same rule keeps crashing on Android 5 and Android 6.
Fatal Exception: java.lang.IncompatibleClassChangeError: Couldn't find kotlin.l.bv
at libcore.reflect.AnnotationAccess.toAnnotationInstance(AnnotationAccess.java:659)
at libcore.reflect.AnnotationAccess.annotationSetToAnnotations(AnnotationAccess.java:633)
at libcore.reflect.AnnotationAccess.getDeclaredAnnotations(AnnotationAccess.java:161)
at java.lang.Class.getDeclaredAnnotations(Class.java:743)
at com.fasterxml.jackson.databind.util.ClassUtil.findClassAnnotations(ClassUtil.java:1095)
at com.fasterxml.jackson.databind.introspect.AnnotatedClassResolver.resolveClassAnnotations(AnnotatedClassResolver.java:153)
at com.fasterxml.jackson.databind.introspect.AnnotatedClassResolver.resolveFully(AnnotatedClassResolver.java:117)
at com.fasterxml.jackson.databind.introspect.AnnotatedClassResolver.resolve(AnnotatedClassResolver.java:69)
at com.fasterxml.jackson.databind.introspect.BasicClassIntrospector._resolveAnnotatedClass(BasicClassIntrospector.java:282)
at com.fasterxml.jackson.databind.introspect.BasicClassIntrospector.collectProperties(BasicClassIntrospector.java:191)
at com.fasterxml.jackson.databind.introspect.BasicClassIntrospector.forDeserialization(BasicClassIntrospector.java:112)
at com.fasterxml.jackson.databind.introspect.BasicClassIntrospector.forDeserialization(BasicClassIntrospector.java:16)
at com.fasterxml.jackson.databind.DeserializationConfig.introspect(DeserializationConfig.java:731)
at com.fasterxml.jackson.databind.deser.DeserializerCache._createDeserializer(DeserializerCache.java:324)
at com.fasterxml.jackson.databind.deser.DeserializerCache._createAndCache2(DeserializerCache.java:264)
at com.fasterxml.jackson.databind.deser.DeserializerCache._createAndCacheValueDeserializer(DeserializerCache.java:244)
at com.fasterxml.jackson.databind.deser.DeserializerCache.findValueDeserializer(DeserializerCache.java:142)
at com.fasterxml.jackson.databind.DeserializationContext.findRootValueDeserializer(DeserializationContext.java:477)
at com.fasterxml.jackson.databind.ObjectReader._prefetchRootDeserializer(ObjectReader.java:1938)
at com.fasterxml.jackson.databind.ObjectReader.forType(ObjectReader.java:677)
at com.fasterxml.jackson.databind.ObjectReader.forType(ObjectReader.java:697)
at com.folioreader.model.locators.ReadLocator$Companion.fromJson(ReadLocator.java:64)
at com.folioreader.model.locators.ReadLocator.fromJson(ReadLocator.java)
at com.storyshots.android.ui.BookDetailActivity.openLocalEpub(BookDetailActivity.java:836)
at com.storyshots.android.ui.BookDetailActivity.openEpub(BookDetailActivity.java:801)
at com.storyshots.android.ui.BookDetailActivity.openEpub(BookDetailActivity.java:785)
at com.storyshots.android.ui.BookDetailActivity.onCreate(BookDetailActivity.java:380)
at android.app.Activity.performCreate(Activity.java:6272)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2387)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2494)
at android.app.ActivityThread.access$900(ActivityThread.java:157)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1356)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5525)
at java.lang.reflect.Method.invoke(Method.java)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:730)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:620)

If I build the old version on new AS, the crash doesn't happen and I cannot reproduce it. But it happens when I upgrade from Google Play builds. I tried adding @keep annotation to the class, it doesn't help. Any idea where is the problem and how could we fix it?