diff --git a/src/main/java/com/android/tools/r8/ir/optimize/enums/EnumUnboxer.java b/src/main/java/com/android/tools/r8/ir/optimize/enums/EnumUnboxer.java
index 11e631a..ebceefd 100644
--- a/src/main/java/com/android/tools/r8/ir/optimize/enums/EnumUnboxer.java
+++ b/src/main/java/com/android/tools/r8/ir/optimize/enums/EnumUnboxer.java
@@ -532,20 +532,21 @@
           }
         }
         if (invokeMethod.isInvokeMethodWithReceiver()) {
-          DexProgramClass enumClass = getEnumUnboxingCandidateOrNull(invokedMethod.holder);
+          DexProgramClass enumClass = getEnumUnboxingCandidateOrNull(invokedMethod.getHolderType());
           if (enumClass != null) {
             markEnumAsUnboxable(Reason.ENUM_METHOD_CALLED_WITH_NULL_RECEIVER, enumClass);
           }
         }
       } else if (use.isFieldPut()) {
-        DexType type = use.asFieldInstruction().getField().type;
-        if (enumUnboxingCandidatesInfo.isCandidate(type)) {
-          eligibleEnums.add(type);
+        DexProgramClass enumClass =
+            getEnumUnboxingCandidateOrNull(use.asFieldInstruction().getField().getType());
+        if (enumClass != null) {
+          eligibleEnums.add(enumClass.getType());
         }
       } else if (use.isReturn()) {
-        DexType returnType = code.method().getReference().proto.returnType;
-        if (enumUnboxingCandidatesInfo.isCandidate(returnType)) {
-          eligibleEnums.add(returnType);
+        DexProgramClass enumClass = getEnumUnboxingCandidateOrNull(code.context().getReturnType());
+        if (enumClass != null) {
+          eligibleEnums.add(enumClass.getType());
         }
       }
     }
diff --git a/src/test/java/com/android/tools/r8/enumunboxing/NullAssignmentToArrayTypeEnumUnboxingTest.java b/src/test/java/com/android/tools/r8/enumunboxing/NullAssignmentToArrayTypeEnumUnboxingTest.java
new file mode 100644
index 0000000..947121d
--- /dev/null
+++ b/src/test/java/com/android/tools/r8/enumunboxing/NullAssignmentToArrayTypeEnumUnboxingTest.java
@@ -0,0 +1,97 @@
+// Copyright (c) 2022, the R8 project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+package com.android.tools.r8.enumunboxing;
+
+import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+import com.android.tools.r8.NeverInline;
+import com.android.tools.r8.TestParameters;
+import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import java.util.List;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+import org.junit.runners.Parameterized.Parameter;
+import org.junit.runners.Parameterized.Parameters;
+
+/** Regression test for b/236618700. */
+@RunWith(Parameterized.class)
+public class NullAssignmentToArrayTypeEnumUnboxingTest extends EnumUnboxingTestBase {
+
+  @Parameter(0)
+  public TestParameters parameters;
+
+  @Parameter(1)
+  public boolean enumValueOptimization;
+
+  @Parameter(2)
+  public EnumKeepRules enumKeepRules;
+
+  @Parameters(name = "{0}, value opt.: {1}, keep: {2}")
+  public static List<Object[]> data() {
+    return enumUnboxingTestParameters();
+  }
+
+  @Test
+  public void test() throws Exception {
+    testForR8(parameters.getBackend())
+        .addInnerClasses(NullAssignmentToArrayTypeEnumUnboxingTest.class)
+        .addKeepMainRule(Main.class)
+        .addKeepRules(enumKeepRules.getKeepRules())
+        .addEnumUnboxingInspector(inspector -> inspector.assertUnboxed(MyEnum.class))
+        .enableInliningAnnotations()
+        .addOptionsModification(opt -> enableEnumOptions(opt, enumValueOptimization))
+        .setMinApi(parameters.getApiLevel())
+        .compile()
+        .inspect(
+            inspector -> {
+              ClassSubject mainClassSubject = inspector.clazz(Main.class);
+              assertThat(mainClassSubject, isPresent());
+
+              MethodSubject clinitMethodSubject = mainClassSubject.clinit();
+              assertThat(clinitMethodSubject, isPresent());
+              assertTrue(
+                  clinitMethodSubject
+                      .streamInstructions()
+                      .anyMatch(InstructionSubject::isFieldAccess));
+            })
+        .run(parameters.getRuntime(), Main.class)
+        .assertSuccessWithOutputLines("A");
+  }
+
+  static class Main {
+
+    static MyEnum[] e;
+
+    static {
+      System.currentTimeMillis(); // To preserve the null assignment below.
+      e = null;
+    }
+
+    public static void main(String[] args) {
+      setField();
+      getField();
+    }
+
+    @NeverInline
+    static void setField() {
+      e = new MyEnum[] {System.currentTimeMillis() > 0 ? MyEnum.A : MyEnum.B};
+    }
+
+    @NeverInline
+    static void getField() {
+      System.out.println(e[0].name());
+    }
+  }
+
+  enum MyEnum {
+    A,
+    B
+  }
+}