@@ -146,7 +146,10 @@ class NodeBuilder extends GeneralizingAstVisitor<DecoratedType> {
   @override
   DecoratedType visitDefaultFormalParameter(DefaultFormalParameter node) {
     var decoratedType = node.parameter.accept(this);
-    if (node.declaredElement.hasRequired || node.defaultValue != null) {
+    if (node.defaultValue != null) {
+      node.defaultValue.accept(this);
+      return null;
+    } else if (node.declaredElement.hasRequired) {
       return null;
     }
     if (decoratedType == null) {
 
@@ -48,7 +48,13 @@ class Variables implements VariableRecorder, VariableRepository {
       throw StateError('No declarated type annotations in ${source.fullName}; '
           'expected one for ${typeAnnotation.toSource()}');
     }
-    return annotationsInSource[_uniqueOffsetForTypeAnnotation(typeAnnotation)];
+    DecoratedTypeAnnotation decoratedTypeAnnotation =
+        annotationsInSource[_uniqueOffsetForTypeAnnotation(typeAnnotation)];
+    if (decoratedTypeAnnotation == null) {
+      throw StateError('Missing declarated type annotation'
+          ' in ${source.fullName}; for ${typeAnnotation.toSource()}');
+    }
+    return decoratedTypeAnnotation;
   }
 
   Map<Source, List<PotentialModification>> getPotentialModifications() =>
 
@@ -1042,6 +1042,17 @@ int/*1*/ f(int/*2*/ i) => i/*3*/;
             hard: true));
   }
 
+  test_functionDeclaration_parameter_named_default_listConst() async {
+    await analyze('''
+void f({List<int/*1*/> i = const <int/*2*/>[]}) {}
+''');
+
+    assertNoUpstreamNullability(decoratedTypeAnnotation('List<int/*1*/>').node);
+    assertEdge(decoratedTypeAnnotation('int/*2*/').node,
+        decoratedTypeAnnotation('int/*1*/').node,
+        hard: false);
+  }
+
   test_functionDeclaration_parameter_named_default_notNull() async {
     await analyze('''
 void f({int i = 1}) {}
Original file line number	Diff line number	Diff line change
`@@ -48,7 +48,13 @@ class Variables implements VariableRecorder, VariableRepository {`
`48`	`48`	`throw StateError('No declarated type annotations in ${source.fullName}; '`
`49`	`49`	`'expected one for ${typeAnnotation.toSource()}');`
`50`	`50`	`}`
`51`		`- return annotationsInSource[_uniqueOffsetForTypeAnnotation(typeAnnotation)];`
	`51`	`+ DecoratedTypeAnnotation decoratedTypeAnnotation =`
	`52`	`+ annotationsInSource[_uniqueOffsetForTypeAnnotation(typeAnnotation)];`
	`53`	`+ if (decoratedTypeAnnotation == null) {`
	`54`	`+ throw StateError('Missing declarated type annotation'`
	`55`	`+ ' in ${source.fullName}; for ${typeAnnotation.toSource()}');`
	`56`	`+ }`
	`57`	`+ return decoratedTypeAnnotation;`
`52`	`58`	`}`
`53`	`59`
`54`	`60`	`Map<Source, List<PotentialModification>> getPotentialModifications() =>`