anchor.diff:          importedIndices: importedIndices,
           useDeferredStrategy: useDeferredSourceReads);
       backendStrategy.prepareCodegenReader(source);
  -    Map<MemberEntity, Deferrable<CodegenResult>> codegenResults =
  +    Map<MemberEntity, CodegenResult> codegenResults =
           source.readMemberMap((MemberEntity member) {
  -      return source.readDeferrable(() {
  -        List<ModularName> modularNames = [];
  -        List<ModularExpression> modularExpressions = [];
  -        CodegenReader reader =
  -            CodegenReaderImpl(closedWorld, modularNames, modularExpressions);
  -        source.registerCodegenReader(reader);
  -        CodegenResult result = CodegenResult.readFromDataSource(
  -            source, modularNames, modularExpressions);
  -        source.deregisterCodegenReader(reader);
  -        return result;
  -      });
  +      List<ModularName> modularNames = [];
  +      List<ModularExpression> modularExpressions = [];
  +      CodegenReader reader =
  +          CodegenReaderImpl(closedWorld, modularNames, modularExpressions);
  +      source.registerCodegenReader(reader);
  +      CodegenResult result = CodegenResult.readFromDataSource(
  +          source, modularNames, modularExpressions);
  +      source.deregisterCodegenReader(reader);
  +      return result;
       });
       _reporter.log('Read ${codegenResults.length} members from ${uri}');
       results.addAll(codegenResults);
  
positive.code: import '../options.dart';
  import '../util/sink_adapter.dart';
  import '../world.dart';
  import 'deferrable.dart';
  import 'serialization.dart';
  
  /// A data class holding some data [T] and the associated [DataSourceIndices].
  
negative.code:       });
      }
      return DeserializedCodegenResults(
          globalTypeInferenceResults, codegenInputs, results);
    }
  
    void _deserializeCodegenInput(
  