diff --git a/pkg/analyzer/lib/src/generated/resolver.dart b/pkg/analyzer/lib/src/generated/resolver.dart
index 6fbe5f2..21b7d76 100644
--- a/pkg/analyzer/lib/src/generated/resolver.dart
+++ b/pkg/analyzer/lib/src/generated/resolver.dart
@@ -739,7 +739,7 @@
 
   void startNullAwareIndexExpression(IndexExpression node) {
     if (_migratableAstInfoProvider.isIndexExpressionNullAware(node) &&
-        _isNonNullableByDefault) {
+        _flowAnalysis != null) {
       _flowAnalysis.flow.nullAwareAccess_rightBegin(
           node.target, node.realTarget.staticType ?? typeProvider.dynamicType);
       _unfinishedNullShorts.add(node.nullShortingTermination);
@@ -750,7 +750,7 @@
     PropertyAccess node,
   ) {
     if (_migratableAstInfoProvider.isPropertyAccessNullAware(node) &&
-        _isNonNullableByDefault) {
+        _flowAnalysis != null) {
       var target = node.target;
       if (target is SimpleIdentifier && target.staticElement is ClassElement) {
         // `?.` to access static methods is equivalent to `.`, so do nothing.
@@ -948,7 +948,7 @@
     InferenceContext.setTypeFromNode(node.target, node);
     node.target.accept(this);
 
-    if (node.isNullAware && _isNonNullableByDefault) {
+    if (node.isNullAware && _flowAnalysis != null) {
       _flowAnalysis.flow.nullAwareAccess_rightBegin(
           node.target, node.target.staticType ?? typeProvider.dynamicType);
       _unfinishedNullShorts.add(node.nullShortingTermination);
@@ -1652,7 +1652,7 @@
     target?.accept(this);
 
     if (_migratableAstInfoProvider.isMethodInvocationNullAware(node) &&
-        _isNonNullableByDefault) {
+        _flowAnalysis != null) {
       if (target is SimpleIdentifier && target.staticElement is ClassElement) {
         // `?.` to access static methods is equivalent to `.`, so do nothing.
       } else {
diff --git a/pkg/analyzer/test/src/dart/resolution/index_expression_test.dart b/pkg/analyzer/test/src/dart/resolution/index_expression_test.dart
index 9652773..fc67be62 100644
--- a/pkg/analyzer/test/src/dart/resolution/index_expression_test.dart
+++ b/pkg/analyzer/test/src/dart/resolution/index_expression_test.dart
@@ -16,6 +16,19 @@
 
 @reflectiveTest
 class IndexExpressionTest extends PubPackageResolutionTest {
+  test_invalid_inDefaultValue_nullAware() async {
+    await assertInvalidTestCode(r'''
+void f({a = b?[0]}) {}
+''');
+
+    assertIndexExpression(
+      findNode.index('[0]'),
+      readElement: null,
+      writeElement: null,
+      type: 'dynamic',
+    );
+  }
+
   test_read() async {
     await assertNoErrorsInCode(r'''
 class A {
diff --git a/pkg/analyzer/test/src/dart/resolution/method_invocation_test.dart b/pkg/analyzer/test/src/dart/resolution/method_invocation_test.dart
index c1ff99b..92450fb 100644
--- a/pkg/analyzer/test/src/dart/resolution/method_invocation_test.dart
+++ b/pkg/analyzer/test/src/dart/resolution/method_invocation_test.dart
@@ -1703,6 +1703,20 @@
     assertSuperExpression(invocation.target);
   }
 
+  test_invalid_inDefaultValue_nullAware() async {
+    await assertInvalidTestCode('''
+void f({a = b?.foo()}) {}
+''');
+
+    assertMethodInvocation2(
+      findNode.methodInvocation('?.foo()'),
+      element: null,
+      typeArgumentTypes: [],
+      invokeType: 'dynamic',
+      type: 'dynamic',
+    );
+  }
+
   test_namedArgument() async {
     var question = typeToStringWithNullability ? '?' : '';
     await assertNoErrorsInCode('''
diff --git a/pkg/analyzer/test/src/dart/resolution/property_access_test.dart b/pkg/analyzer/test/src/dart/resolution/property_access_test.dart
index 313cd97..645d77a 100644
--- a/pkg/analyzer/test/src/dart/resolution/property_access_test.dart
+++ b/pkg/analyzer/test/src/dart/resolution/property_access_test.dart
@@ -238,6 +238,30 @@
     }
   }
 
+  test_invalid_inDefaultValue_nullAware() async {
+    await assertInvalidTestCode('''
+void f({a = b?.foo}) {}
+''');
+
+    assertPropertyAccess2(
+      findNode.propertyAccess('?.foo'),
+      element: null,
+      type: 'dynamic',
+    );
+  }
+
+  test_invalid_inDefaultValue_nullAware_cascade() async {
+    await assertInvalidTestCode('''
+void f({a = b?..foo}) {}
+''');
+
+    assertPropertyAccess2(
+      findNode.propertyAccess('?..foo'),
+      element: null,
+      type: 'dynamic',
+    );
+  }
+
   test_ofExtension_read() async {
     await assertNoErrorsInCode('''
 class A {}
diff --git a/pkg/analyzer/test/src/dart/resolution/resolution.dart b/pkg/analyzer/test/src/dart/resolution/resolution.dart
index b91cab9..5e7e81c 100644
--- a/pkg/analyzer/test/src/dart/resolution/resolution.dart
+++ b/pkg/analyzer/test/src/dart/resolution/resolution.dart
@@ -448,6 +448,13 @@
         expectedPrefix: expectedPrefix);
   }
 
+  /// Resolve the [code], and ensure that it can be resolved without a crash,
+  /// and is invalid, i.e. produces a diagnostic.
+  Future<void> assertInvalidTestCode(String code) async {
+    await resolveTestCode(code);
+    assertHasTestErrors();
+  }
+
   void assertInvokeType(Expression node, String expected) {
     DartType actual;
     if (node is BinaryExpression) {