| Index: lib/compiler/implementation/ssa/optimize.dart | 
| diff --git a/lib/compiler/implementation/ssa/optimize.dart b/lib/compiler/implementation/ssa/optimize.dart | 
| index 5abf8de4e536eca68d63efdbcf77b3adc61a36f4..544f529b302ec5b4850773d661f236a2b6acfa4e 100644 | 
| --- a/lib/compiler/implementation/ssa/optimize.dart | 
| +++ b/lib/compiler/implementation/ssa/optimize.dart | 
| @@ -195,7 +195,8 @@ class SsaConstantFolder extends HBaseVisitor implements OptimizationPhase { | 
| } | 
|  | 
| HInstruction visitIs(HIs node) { | 
| -    Element element = node.typeExpression; | 
| +    Type type = node.typeName; | 
| +    Element element = type.element; | 
| if (element.kind === ElementKind.TYPE_VARIABLE) { | 
| compiler.unimplemented("visitIs for type variables"); | 
| } | 
|  |