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sdk/lib/_internal/compiler/implementation/apiimpl.dart

Index: sdk/lib/_internal/compiler/implementation/apiimpl.dart
diff --git a/sdk/lib/_internal/compiler/implementation/apiimpl.dart b/sdk/lib/_internal/compiler/implementation/apiimpl.dart
index f6434a018f9b6571bcb6a391eddf68fcf186f660..3297e5229d0374a28f5478ed17a99e5bb1bb5bb7 100644
--- a/sdk/lib/_internal/compiler/implementation/apiimpl.dart
+++ b/sdk/lib/_internal/compiler/implementation/apiimpl.dart
@@ -43,7 +43,8 @@ class Compiler extends leg.Compiler {
                           '--report-sdk-use-of-deprecated-language-features'),
             strips: getStrips(options),
             enableConcreteTypeInference:
-                hasOption(options, '--enable-concrete-type-inference')) {
+                hasOption(options, '--enable-concrete-type-inference'),
+            preserveComments: hasOption(options, '--preserve-comments')) {
     if (!libraryRoot.path.endsWith("/")) {
       throw new ArgumentError("libraryRoot must end with a /");
     }