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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 73c4f28ff29f76946881befcb0033c596a32cd12..ce5498fdb5e9b5992d52f4f36aacff8fa423cab3 100644
--- a/sdk/lib/_internal/compiler/implementation/apiimpl.dart
+++ b/sdk/lib/_internal/compiler/implementation/apiimpl.dart
@@ -42,7 +42,8 @@ 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 /");
     }