diff --git a/src/main/java/com/android/tools/r8/Version.java b/src/main/java/com/android/tools/r8/Version.java
index 5512001..23ad589 100644
--- a/src/main/java/com/android/tools/r8/Version.java
+++ b/src/main/java/com/android/tools/r8/Version.java
@@ -11,7 +11,7 @@
 
   // This field is accessed from release scripts using simple pattern matching.
   // Therefore, changing this field could break our release scripts.
-  public static final String LABEL = "1.6.69";
+  public static final String LABEL = "1.6.70";
 
   private Version() {
   }
diff --git a/src/main/java/com/android/tools/r8/graph/DexClass.java b/src/main/java/com/android/tools/r8/graph/DexClass.java
index 7ce2685..4cef294 100644
--- a/src/main/java/com/android/tools/r8/graph/DexClass.java
+++ b/src/main/java/com/android/tools/r8/graph/DexClass.java
@@ -734,11 +734,15 @@
   }
 
   public boolean classInitializationMayHaveSideEffects(AppView<?> appView) {
-    return classInitializationMayHaveSideEffects(appView, Predicates.alwaysFalse());
+    return classInitializationMayHaveSideEffects(
+        appView, Predicates.alwaysFalse(), Sets.newIdentityHashSet());
   }
 
   public boolean classInitializationMayHaveSideEffects(
-      AppView<?> appView, Predicate<DexType> ignore) {
+      AppView<?> appView, Predicate<DexType> ignore, Set<DexType> seen) {
+    if (!seen.add(type)) {
+      return false;
+    }
     if (ignore.test(type)) {
       return false;
     }
@@ -756,7 +760,7 @@
     if (defaultValuesForStaticFieldsMayTriggerAllocation()) {
       return true;
     }
-    return initializationOfParentTypesMayHaveSideEffects(appView, ignore);
+    return initializationOfParentTypesMayHaveSideEffects(appView, ignore, seen);
   }
 
   private boolean hasClassInitializerThatCannotBePostponed() {
@@ -781,17 +785,19 @@
   }
 
   public boolean initializationOfParentTypesMayHaveSideEffects(AppView<?> appView) {
-    return initializationOfParentTypesMayHaveSideEffects(appView, Predicates.alwaysFalse());
+    return initializationOfParentTypesMayHaveSideEffects(
+        appView, Predicates.alwaysFalse(), Sets.newIdentityHashSet());
   }
 
   public boolean initializationOfParentTypesMayHaveSideEffects(
-      AppView<?> appView, Predicate<DexType> ignore) {
+      AppView<?> appView, Predicate<DexType> ignore, Set<DexType> seen) {
     for (DexType iface : interfaces.values) {
-      if (iface.classInitializationMayHaveSideEffects(appView, ignore)) {
+      if (iface.classInitializationMayHaveSideEffects(appView, ignore, seen)) {
         return true;
       }
     }
-    if (superType != null && superType.classInitializationMayHaveSideEffects(appView, ignore)) {
+    if (superType != null
+        && superType.classInitializationMayHaveSideEffects(appView, ignore, seen)) {
       return true;
     }
     return false;
diff --git a/src/main/java/com/android/tools/r8/graph/DexEncodedField.java b/src/main/java/com/android/tools/r8/graph/DexEncodedField.java
index 383f816..874b9ff 100644
--- a/src/main/java/com/android/tools/r8/graph/DexEncodedField.java
+++ b/src/main/java/com/android/tools/r8/graph/DexEncodedField.java
@@ -12,6 +12,7 @@
 import com.android.tools.r8.ir.optimize.info.FieldOptimizationInfo;
 import com.android.tools.r8.ir.optimize.info.MutableFieldOptimizationInfo;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
+import com.google.common.collect.Sets;
 
 public class DexEncodedField extends KeyedDexItem<DexField> {
   public static final DexEncodedField[] EMPTY_ARRAY = {};
@@ -163,7 +164,8 @@
           appView,
           // Types that are a super type of the current context are guaranteed to be initialized
           // already.
-          type -> appView.isSubtype(context, type).isTrue())) {
+          type -> appView.isSubtype(context, type).isTrue(),
+          Sets.newIdentityHashSet())) {
         // Ignore class initialization side-effects for dead proto extension fields to ensure that
         // we force replace these field reads by null.
         boolean ignore =
diff --git a/src/main/java/com/android/tools/r8/graph/DexType.java b/src/main/java/com/android/tools/r8/graph/DexType.java
index b0e5373..81fc24c 100644
--- a/src/main/java/com/android/tools/r8/graph/DexType.java
+++ b/src/main/java/com/android/tools/r8/graph/DexType.java
@@ -22,8 +22,10 @@
 import com.android.tools.r8.utils.InternalOptions.OutlineOptions;
 import com.android.tools.r8.utils.Pair;
 import com.google.common.base.Predicates;
+import com.google.common.collect.Sets;
 import java.util.Arrays;
 import java.util.Map;
+import java.util.Set;
 import java.util.function.Predicate;
 
 public class DexType extends DexReference implements PresortedComparable<DexType> {
@@ -51,23 +53,26 @@
   }
 
   public boolean classInitializationMayHaveSideEffects(AppView<?> appView) {
-    return classInitializationMayHaveSideEffects(appView, Predicates.alwaysFalse());
+    return classInitializationMayHaveSideEffects(
+        appView, Predicates.alwaysFalse(), Sets.newIdentityHashSet());
   }
 
   public boolean classInitializationMayHaveSideEffects(
-      AppView<?> appView, Predicate<DexType> ignore) {
+      AppView<?> appView, Predicate<DexType> ignore, Set<DexType> seen) {
     DexClass clazz = appView.definitionFor(this);
-    return clazz == null || clazz.classInitializationMayHaveSideEffects(appView, ignore);
+    return clazz == null || clazz.classInitializationMayHaveSideEffects(appView, ignore, seen);
   }
 
   public boolean initializationOfParentTypesMayHaveSideEffects(AppView<?> appView) {
-    return initializationOfParentTypesMayHaveSideEffects(appView, Predicates.alwaysFalse());
+    return initializationOfParentTypesMayHaveSideEffects(
+        appView, Predicates.alwaysFalse(), Sets.newIdentityHashSet());
   }
 
   public boolean initializationOfParentTypesMayHaveSideEffects(
-      AppView<?> appView, Predicate<DexType> ignore) {
+      AppView<?> appView, Predicate<DexType> ignore, Set<DexType> seen) {
     DexClass clazz = appView.definitionFor(this);
-    return clazz == null || clazz.initializationOfParentTypesMayHaveSideEffects(appView, ignore);
+    return clazz == null
+        || clazz.initializationOfParentTypesMayHaveSideEffects(appView, ignore, seen);
   }
 
   public boolean isAlwaysNull(AppView<AppInfoWithLiveness> appView) {
diff --git a/src/main/java/com/android/tools/r8/ir/code/FieldInstruction.java b/src/main/java/com/android/tools/r8/ir/code/FieldInstruction.java
index 77e084d..0529d21 100644
--- a/src/main/java/com/android/tools/r8/ir/code/FieldInstruction.java
+++ b/src/main/java/com/android/tools/r8/ir/code/FieldInstruction.java
@@ -15,6 +15,7 @@
 import com.android.tools.r8.ir.analysis.AbstractError;
 import com.android.tools.r8.ir.analysis.type.TypeLatticeElement;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
+import com.google.common.collect.Sets;
 import java.util.Collections;
 import java.util.List;
 
@@ -122,7 +123,8 @@
       if (field.holder.classInitializationMayHaveSideEffects(
           appView,
           // Types that are a super type of `context` are guaranteed to be initialized already.
-          type -> appView.isSubtype(context, type).isTrue())) {
+          type -> appView.isSubtype(context, type).isTrue(),
+          Sets.newIdentityHashSet())) {
         return AbstractError.top();
       }
     }
diff --git a/src/main/java/com/android/tools/r8/ir/code/InvokeStatic.java b/src/main/java/com/android/tools/r8/ir/code/InvokeStatic.java
index 4f42386..94bf6c0 100644
--- a/src/main/java/com/android/tools/r8/ir/code/InvokeStatic.java
+++ b/src/main/java/com/android/tools/r8/ir/code/InvokeStatic.java
@@ -23,6 +23,7 @@
 import com.android.tools.r8.ir.optimize.InliningConstraints;
 import com.android.tools.r8.ir.optimize.InliningOracle;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
+import com.google.common.collect.Sets;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
@@ -204,7 +205,8 @@
                     appView,
                     // Types that are a super type of `context` are guaranteed to be initialized
                     // already.
-                    type -> appView.isSubtype(context, type).isTrue());
+                    type -> appView.isSubtype(context, type).isTrue(),
+                    Sets.newIdentityHashSet());
       }
 
       return targetMayHaveSideEffects;
diff --git a/src/main/java/com/android/tools/r8/ir/code/NewInstance.java b/src/main/java/com/android/tools/r8/ir/code/NewInstance.java
index 7e6fffe..9fca9f0 100644
--- a/src/main/java/com/android/tools/r8/ir/code/NewInstance.java
+++ b/src/main/java/com/android/tools/r8/ir/code/NewInstance.java
@@ -21,6 +21,7 @@
 import com.android.tools.r8.ir.conversion.DexBuilder;
 import com.android.tools.r8.ir.optimize.Inliner.ConstraintWithTarget;
 import com.android.tools.r8.ir.optimize.InliningConstraints;
+import com.google.common.collect.Sets;
 
 public class NewInstance extends Instruction {
 
@@ -164,7 +165,8 @@
     if (definition.classInitializationMayHaveSideEffects(
         appView,
         // Types that are a super type of `context` are guaranteed to be initialized already.
-        type -> appView.isSubtype(context, type).isTrue())) {
+        type -> appView.isSubtype(context, type).isTrue(),
+        Sets.newIdentityHashSet())) {
       return true;
     }
 
@@ -192,7 +194,8 @@
       return clazz.classInitializationMayHaveSideEffects(
           appView,
           // Types that are a super type of `context` are guaranteed to be initialized already.
-          type -> appView.isSubtype(context, type).isTrue());
+          type -> appView.isSubtype(context, type).isTrue(),
+          Sets.newIdentityHashSet());
     } else {
       // In D8, this instruction may trigger class initialization if the holder of the field is
       // different from the current context.
diff --git a/src/main/java/com/android/tools/r8/ir/code/StaticGet.java b/src/main/java/com/android/tools/r8/ir/code/StaticGet.java
index e6b7a1c..e09d769 100644
--- a/src/main/java/com/android/tools/r8/ir/code/StaticGet.java
+++ b/src/main/java/com/android/tools/r8/ir/code/StaticGet.java
@@ -27,6 +27,7 @@
 import com.android.tools.r8.ir.conversion.DexBuilder;
 import com.android.tools.r8.ir.optimize.Inliner.ConstraintWithTarget;
 import com.android.tools.r8.ir.optimize.InliningConstraints;
+import com.google.common.collect.Sets;
 import java.util.Set;
 
 public class StaticGet extends FieldInstruction {
@@ -217,7 +218,8 @@
       return holder.classInitializationMayHaveSideEffects(
           appView,
           // Types that are a super type of `context` are guaranteed to be initialized already.
-          type -> appView.isSubtype(context, type).isTrue());
+          type -> appView.isSubtype(context, type).isTrue(),
+          Sets.newIdentityHashSet());
     } else {
       // In D8, this instruction may trigger class initialization if the holder of the field is
       // different from the current context.
diff --git a/src/main/java/com/android/tools/r8/ir/code/StaticPut.java b/src/main/java/com/android/tools/r8/ir/code/StaticPut.java
index 63e5c10..c9bab8b 100644
--- a/src/main/java/com/android/tools/r8/ir/code/StaticPut.java
+++ b/src/main/java/com/android/tools/r8/ir/code/StaticPut.java
@@ -28,6 +28,7 @@
 import com.android.tools.r8.ir.regalloc.RegisterAllocator;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
 import com.android.tools.r8.shaking.ProguardMemberRule;
+import com.google.common.collect.Sets;
 
 public class StaticPut extends FieldInstruction {
 
@@ -235,7 +236,8 @@
       return holder.classInitializationMayHaveSideEffects(
           appView,
           // Types that are a super type of `context` are guaranteed to be initialized already.
-          type -> appView.isSubtype(context, type).isTrue());
+          type -> appView.isSubtype(context, type).isTrue(),
+          Sets.newIdentityHashSet());
     } else {
       // In D8, this instruction may trigger class initialization if the holder of the field is
       // different from the current context.
diff --git a/src/main/java/com/android/tools/r8/ir/optimize/RedundantFieldLoadElimination.java b/src/main/java/com/android/tools/r8/ir/optimize/RedundantFieldLoadElimination.java
index 5577a8c..f362ef7 100644
--- a/src/main/java/com/android/tools/r8/ir/optimize/RedundantFieldLoadElimination.java
+++ b/src/main/java/com/android/tools/r8/ir/optimize/RedundantFieldLoadElimination.java
@@ -186,7 +186,8 @@
           if (newInstance.clazz.classInitializationMayHaveSideEffects(
               appView,
               // Types that are a super type of `context` are guaranteed to be initialized already.
-              type -> appView.isSubtype(context, type).isTrue())) {
+              type -> appView.isSubtype(context, type).isTrue(),
+              Sets.newIdentityHashSet())) {
             killAllActiveFields();
           }
         } else {
diff --git a/src/main/java/com/android/tools/r8/shaking/VerticalClassMerger.java b/src/main/java/com/android/tools/r8/shaking/VerticalClassMerger.java
index b279af2..4a84371 100644
--- a/src/main/java/com/android/tools/r8/shaking/VerticalClassMerger.java
+++ b/src/main/java/com/android/tools/r8/shaking/VerticalClassMerger.java
@@ -468,7 +468,8 @@
     // We basically can't move the clinit, since it is not called when implementing classes have
     // their clinit called - except when the interface has a default method.
     if ((clazz.hasClassInitializer() && targetClass.hasClassInitializer())
-        || targetClass.classInitializationMayHaveSideEffects(appView, type -> type == clazz.type)
+        || targetClass.classInitializationMayHaveSideEffects(
+            appView, type -> type == clazz.type, Sets.newIdentityHashSet())
         || (clazz.isInterface() && clazz.classInitializationMayHaveSideEffects(appView))) {
       // TODO(herhut): Handle class initializers.
       if (Log.ENABLED) {