closure.diff

diff --git a/src/main/shadow/build/closure.clj b/src/main/shadow/build/closure.clj
index 362450be..2912b866 100644
--- a/src/main/shadow/build/closure.clj
+++ b/src/main/shadow/build/closure.clj
@@ -23,7 +23,7 @@
                                          CommandLineRunner VariableMap SourceMapInput DiagnosticGroups
                                          CheckLevel JSModule CompilerOptions$LanguageMode
                                          Result ShadowAccess
-                                         SourceMap$DetailLevel SourceMap$Format ClosureCodingConvention CompilationLevel AnonymousFunctionNamingPolicy DiagnosticGroup NodeTraversal StrictModeCheck VariableRenamingPolicy PropertyRenamingPolicy PhaseOptimizer)
+                                         SourceMap$DetailLevel SourceMap$Format ClosureCodingConvention CompilationLevel AnonymousFunctionNamingPolicy DiagnosticGroup NodeTraversal StrictModeCheck VariableRenamingPolicy PropertyRenamingPolicy PhaseOptimizer CompilerOptions$Reach)
            (shadow.build.closure ReplaceCLJSConstants NodeEnvInlinePass ReplaceRequirePass PropertyCollector NodeStuffInlinePass FindSurvivingRequireCalls ClearUnassignedJsRequires)
            (com.google.javascript.jscomp.deps ModuleLoader$ResolutionMode)
            (java.nio.charset Charset)
@@ -136,6 +136,15 @@
           :mapped AnonymousFunctionNamingPolicy/MAPPED
           (throw (IllegalArgumentException. (str "Invalid :anon-fn-naming-policy value " policy " - only :off, :unmapped, :mapped permitted")))))))
 
+  (when (contains? opts :remove-unused-variables)
+    (let [policy (:remove-unused-variables opts)
+          reach (case policy
+                  :none CompilerOptions$Reach/NONE
+                  :local-only CompilerOptions$Reach/LOCAL_ONLY
+                  :all CompilerOptions$Reach/ALL
+                  (throw (IllegalArgumentException. (str "Invalid :remove-unused-variables value " policy " - only :none, :local-only, :all permitted"))))]
+      (.setRemoveUnusedVariables closure-opts reach)))
+
   (when-let [lang-key (:language-in opts)]
     (.setLanguageIn closure-opts (lang-key->lang-mode lang-key)))