diff --git a/src/main/java/com/android/tools/r8/synthesis/SyntheticFinalization.java b/src/main/java/com/android/tools/r8/synthesis/SyntheticFinalization.java
index eb764c0..822fa38 100644
--- a/src/main/java/com/android/tools/r8/synthesis/SyntheticFinalization.java
+++ b/src/main/java/com/android/tools/r8/synthesis/SyntheticFinalization.java
@@ -744,8 +744,6 @@
       }
       DexClass clazz = appView.appInfo().definitionForWithoutExistenceAssert(externalType);
       if (clazz != null && isNotSyntheticType(clazz.type)) {
-        assert options.testing.allowConflictingSyntheticTypes
-            : "Unexpected creation of an existing external synthetic type: " + clazz;
         externalType = null;
       }
     } while (externalType == null);
diff --git a/src/main/java/com/android/tools/r8/utils/InternalOptions.java b/src/main/java/com/android/tools/r8/utils/InternalOptions.java
index 2612127..1fecada 100644
--- a/src/main/java/com/android/tools/r8/utils/InternalOptions.java
+++ b/src/main/java/com/android/tools/r8/utils/InternalOptions.java
@@ -1931,8 +1931,6 @@
     // minified field names instead of original field names.
     public boolean enableRecordModeling = true;
 
-    public boolean allowConflictingSyntheticTypes = false;
-
     // Flag to allow processing of resources in D8. A data resource consumer still needs to be
     // specified.
     public boolean enableD8ResourcesPassThrough = false;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaNamingConflictTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaNamingConflictTest.java
index 1a6e364..e862e2e 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaNamingConflictTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaNamingConflictTest.java
@@ -58,7 +58,6 @@
         .addProgramClassFileData(getConflictingNameClass())
         .addProgramClassFileData(getTransformedMainClass())
         .setMinApi(parameters.getApiLevel())
-        .addOptionsModification(o -> o.testing.allowConflictingSyntheticTypes = true)
         .run(parameters.getRuntime(), TestClass.class)
         .assertSuccessWithOutput(EXPECTED);
   }
@@ -70,7 +69,6 @@
         .addProgramClassFileData(getConflictingNameClass())
         .addProgramClassFileData(getTransformedMainClass())
         .setMinApi(parameters.getApiLevel())
-        .addOptionsModification(o -> o.testing.allowConflictingSyntheticTypes = true)
         .addKeepMainRule(TestClass.class)
         // Ensure that R8 cannot remove or rename the conflicting name.
         .addKeepClassAndMembersRules(CONFLICTING_NAME.getTypeName())
diff --git a/src/test/java/com/android/tools/r8/smali/OutlineTest.java b/src/test/java/com/android/tools/r8/smali/OutlineTest.java
index 10d96c1..56435ed 100644
--- a/src/test/java/com/android/tools/r8/smali/OutlineTest.java
+++ b/src/test/java/com/android/tools/r8/smali/OutlineTest.java
@@ -950,10 +950,7 @@
     for (int i = 1; i < count; i++) {
       // Build a new application with the Outliner class.
       originalApplication = processedApplication;
-      processedApplication =
-          processApplication(
-              originalApplication,
-              options.andThen(o -> o.testing.allowConflictingSyntheticTypes = true));
+      processedApplication = processApplication(originalApplication, options);
       assertEquals((i + 1) * 3, getNumberOfProgramClasses(processedApplication));
     }