diff --git a/dev/core/src/com/google/gwt/dev/javac/CachedCompilationUnit.java b/dev/core/src/com/google/gwt/dev/javac/CachedCompilationUnit.java
index 2ea39a4..f9eecd3 100644
--- a/dev/core/src/com/google/gwt/dev/javac/CachedCompilationUnit.java
+++ b/dev/core/src/com/google/gwt/dev/javac/CachedCompilationUnit.java
@@ -45,6 +45,7 @@
   private final boolean isError;
   private final boolean isGenerated;
   private final boolean isSuperSource;
+  private final boolean hasJsInteropRootType;
   private transient List<JsniMethod> jsniMethods;
   private final long lastModified;
   private final MethodArgNamesLookup methodArgNamesLookup;
@@ -64,6 +65,7 @@
       String resourceLocation) {
     assert unit != null;
     this.compiledClasses = CompiledClass.copyForUnit(unit.getCompiledClasses(), this);
+    this.hasJsInteropRootType = unit.hasJsInteropRootType;
     this.contentId = unit.getContentId();
     this.dependencies = unit.getDependencies();
     this.resourcePath = unit.getResourcePath();
@@ -94,6 +96,7 @@
   CachedCompilationUnit(CompilationUnit unit, long astToken) {
     assert unit != null;
     this.compiledClasses = CompiledClass.copyForUnit(unit.getCompiledClasses(), this);
+    this.hasJsInteropRootType = unit.hasJsInteropRootType();
     this.contentId = unit.getContentId();
     this.dependencies = unit.getDependencies();
     this.resourcePath = unit.getResourcePath();
@@ -181,6 +184,11 @@
   }
 
   @Override
+  boolean hasJsInteropRootType() {
+    return hasJsInteropRootType;
+  }
+
+  @Override
   ContentId getContentId() {
     return contentId;
   }
diff --git a/dev/core/src/com/google/gwt/dev/javac/CompilationState.java b/dev/core/src/com/google/gwt/dev/javac/CompilationState.java
index c3a1079..2979a4a 100644
--- a/dev/core/src/com/google/gwt/dev/javac/CompilationState.java
+++ b/dev/core/src/com/google/gwt/dev/javac/CompilationState.java
@@ -24,6 +24,9 @@
 import com.google.gwt.dev.util.log.speedtracer.SpeedTracerLogger;
 import com.google.gwt.dev.util.log.speedtracer.SpeedTracerLogger.Event;
 import com.google.gwt.thirdparty.guava.common.annotations.VisibleForTesting;
+import com.google.gwt.thirdparty.guava.common.base.Function;
+import com.google.gwt.thirdparty.guava.common.base.Predicates;
+import com.google.gwt.thirdparty.guava.common.collect.FluentIterable;
 
 import java.util.Collection;
 import java.util.Collections;
@@ -166,6 +169,18 @@
     return exposedUnits;
   }
 
+  public Iterable<String> getQualifiedJsInteropRootTypesNames() {
+    Function<CompilationUnit, String> toRootTypeName = new Function<CompilationUnit, String>() {
+      @Override
+      public String apply(CompilationUnit compilationUnit) {
+        return compilationUnit.hasJsInteropRootType() ? compilationUnit.getTypeName() : null;
+      }
+    };
+    return FluentIterable.from(unitMap.values())
+        .transform(toRootTypeName)
+        .filter(Predicates.notNull());
+  }
+
   public CompilerContext getCompilerContext() {
     return compilerContext;
   }
diff --git a/dev/core/src/com/google/gwt/dev/javac/CompilationUnit.java b/dev/core/src/com/google/gwt/dev/javac/CompilationUnit.java
index a340edf..f9d2866 100644
--- a/dev/core/src/com/google/gwt/dev/javac/CompilationUnit.java
+++ b/dev/core/src/com/google/gwt/dev/javac/CompilationUnit.java
@@ -445,6 +445,12 @@
 
   abstract CategorizedProblem[] getProblems();
 
+  /**
+   * Returns true if this compilation unit has any JsInterop root types (i.e. type with an export or
+   * a JsType).
+   */
+  abstract boolean hasJsInteropRootType();
+
   private List<String> getJdtClassNames(String topLevelClass) {
     List<String> classNames = new ArrayList<String>();
     for (CompiledClass cc : getCompiledClasses()) {
diff --git a/dev/core/src/com/google/gwt/dev/javac/CompilationUnitImpl.java b/dev/core/src/com/google/gwt/dev/javac/CompilationUnitImpl.java
index 43c8102..18cf8d3 100644
--- a/dev/core/src/com/google/gwt/dev/javac/CompilationUnitImpl.java
+++ b/dev/core/src/com/google/gwt/dev/javac/CompilationUnitImpl.java
@@ -18,6 +18,8 @@
 import com.google.gwt.dev.jjs.ast.JDeclaredType;
 import com.google.gwt.dev.jjs.ast.JProgram;
 import com.google.gwt.dev.util.collect.Lists;
+import com.google.gwt.thirdparty.guava.common.base.Predicate;
+import com.google.gwt.thirdparty.guava.common.collect.Iterables;
 
 import org.eclipse.jdt.core.compiler.CategorizedProblem;
 
@@ -37,6 +39,7 @@
   private final Dependencies dependencies;
   private final List<CompiledClass> exposedCompiledClasses;
   private final boolean hasErrors;
+  private final boolean hasJsInteropRootType;
   private final List<JsniMethod> jsniMethods;
   private final MethodArgNamesLookup methodArgs;
   private final CategorizedProblem[] problems;
@@ -59,6 +62,11 @@
       }
     }
     this.hasErrors = hasAnyErrors;
+    this.hasJsInteropRootType = Iterables.any(types, new Predicate<JDeclaredType>() {
+      @Override public boolean apply(JDeclaredType type) {
+        return type.hasAnyExports() || type.isOrExtendsJsType();
+      }
+    });
     for (CompiledClass cc : compiledClasses) {
       cc.initUnit(this);
     }
@@ -100,6 +108,11 @@
   }
 
   @Override
+  boolean hasJsInteropRootType() {
+    return hasJsInteropRootType;
+  }
+
+  @Override
   Dependencies getDependencies() {
     return dependencies;
   }
diff --git a/dev/core/src/com/google/gwt/dev/javac/CompiledClass.java b/dev/core/src/com/google/gwt/dev/javac/CompiledClass.java
index e0e7e25..e53bbde 100644
--- a/dev/core/src/com/google/gwt/dev/javac/CompiledClass.java
+++ b/dev/core/src/com/google/gwt/dev/javac/CompiledClass.java
@@ -44,7 +44,6 @@
     if (in == null) {
       return null;
     }
-    CompiledClass[] orig = new CompiledClass[in.size()];
     List<CompiledClass> copy = new ArrayList<CompiledClass>();
 
     Map<CompiledClass, CompiledClass> enclosingClassMap = new HashMap<CompiledClass, CompiledClass>();
diff --git a/dev/core/src/com/google/gwt/dev/jjs/JavaToJavaScriptCompiler.java b/dev/core/src/com/google/gwt/dev/jjs/JavaToJavaScriptCompiler.java
index 185ed0f..3e3f72c 100644
--- a/dev/core/src/com/google/gwt/dev/jjs/JavaToJavaScriptCompiler.java
+++ b/dev/core/src/com/google/gwt/dev/jjs/JavaToJavaScriptCompiler.java
@@ -148,6 +148,7 @@
 import com.google.gwt.soyc.io.ArtifactsOutputDirectory;
 import com.google.gwt.thirdparty.guava.common.annotations.VisibleForTesting;
 import com.google.gwt.thirdparty.guava.common.collect.ImmutableMap;
+import com.google.gwt.thirdparty.guava.common.collect.Iterables;
 import com.google.gwt.thirdparty.guava.common.collect.Lists;
 import com.google.gwt.thirdparty.guava.common.collect.Multimap;
 import com.google.gwt.thirdparty.guava.common.collect.Sets;
@@ -158,7 +159,6 @@
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.lang.annotation.Annotation;
 import java.lang.management.ManagementFactory;
 import java.util.ArrayList;
 import java.util.Collection;
@@ -891,8 +891,6 @@
 
     protected RebindPermutationOracle rpo;
     protected String[] entryPointTypeNames;
-    private static final String JS_EXPORT_ANN = "com.google.gwt.core.client.js.JsExport";
-    private static final String JS_TYPE_ANN = "com.google.gwt.core.client.js.JsType";
 
     public Precompiler(RebindPermutationOracle rpo, String[] entryPointTypeNames) {
       this.rpo = rpo;
@@ -1036,7 +1034,7 @@
       CompilationState compilationState = rpo.getCompilationState();
       Memory.maybeDumpMemory("CompStateBuilt");
       recordJsoTypes(compilationState.getTypeOracle());
-      populateRootTypes(allRootTypes, additionalRootTypes, compilationState.getTypeOracle());
+      populateRootTypes(allRootTypes, additionalRootTypes, compilationState);
       String entryMethodHolderTypeName =
           buildEntryMethodHolder(rpo.getGeneratorContext(), allRootTypes);
       beforeUnifyAst(allRootTypes);
@@ -1132,7 +1130,10 @@
     }
 
     private void populateRootTypes(Set<String> allRootTypes, String[] additionalRootTypes,
-        TypeOracle typeOracle) {
+        CompilationState compilationState) {
+      if (jprogram.typeOracle.isJsInteropEnabled()) {
+        Iterables.addAll(allRootTypes, compilationState.getQualifiedJsInteropRootTypesNames());
+      }
       Collections.addAll(allRootTypes, entryPointTypeNames);
       Collections.addAll(allRootTypes, additionalRootTypes);
       allRootTypes.addAll(JProgram.CODEGEN_TYPES_SET);
@@ -1141,49 +1142,11 @@
        * Add all SingleJsoImpl types that we know about. It's likely that the concrete types are
        * never explicitly referenced.
        */
+      TypeOracle typeOracle = compilationState.getTypeOracle();
       for (com.google.gwt.core.ext.typeinfo.JClassType singleJsoIntf :
           typeOracle.getSingleJsoImplInterfaces()) {
         allRootTypes.add(typeOracle.getSingleJsoImpl(singleJsoIntf).getQualifiedSourceName());
       }
-
-      if (jprogram.typeOracle.isJsInteropEnabled()) {
-        // find any types with @JsExport could be entry points as well
-        nextType:
-        for (com.google.gwt.dev.javac.typemodel.JClassType type :
-            typeOracle.getTypes()) {
-          for (Annotation ann : type.getAnnotations()) {
-            // If the type immediately exports symbols to JS.
-            if (ann.annotationType().getName().equals(JS_EXPORT_ANN)) {
-              allRootTypes.add(type.getQualifiedSourceName());
-              continue nextType;
-            }
-          }
-          if (isJsType(type)) {
-            // If the type or any transitive interface is a JS type.
-            allRootTypes.add(type.getQualifiedSourceName());
-          }
-        }
-      }
-    }
-
-    /**
-     * Returns true if the type, or any super-interface has a JsType
-     * annotation.
-     */
-    private boolean isJsType(com.google.gwt.dev.javac.typemodel.JClassType type) {
-      for (Annotation ann : type.getAnnotations()) {
-        if (ann.annotationType().getName().equals(JS_TYPE_ANN)) {
-          return true;
-        }
-      }
-
-      for (com.google.gwt.dev.javac.typemodel.JClassType intf : type
-          .getImplementedInterfaces()) {
-         if (isJsType(intf)) {
-           return true;
-         }
-      }
-      return false;
     }
 
     private void recordJsoTypes(TypeOracle typeOracle) {
diff --git a/dev/core/src/com/google/gwt/dev/jjs/ast/JDeclaredType.java b/dev/core/src/com/google/gwt/dev/jjs/ast/JDeclaredType.java
index d50a567..167b15c 100755
--- a/dev/core/src/com/google/gwt/dev/jjs/ast/JDeclaredType.java
+++ b/dev/core/src/com/google/gwt/dev/jjs/ast/JDeclaredType.java
@@ -309,6 +309,34 @@
     return jsInteropType != JsInteropType.NONE;
   }
 
+  public boolean isOrExtendsJsType() {
+    if (isJsType()) {
+      return true;
+    }
+    for (JInterfaceType subIntf : getImplements()) {
+      if (subIntf.isJsType()) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  public boolean hasAnyExports() {
+    for (JMethod method : getMethods()) {
+      if (method.isExported()) {
+        return true;
+      }
+    }
+
+    for (JField field : getFields()) {
+      if (field.isExported()) {
+        return true;
+      }
+    }
+
+    return false;
+  }
+
   public JsInteropType getJsInteropType() {
     return jsInteropType;
   }
diff --git a/dev/core/src/com/google/gwt/dev/jjs/ast/JField.java b/dev/core/src/com/google/gwt/dev/jjs/ast/JField.java
index c1696db..353d23b 100644
--- a/dev/core/src/com/google/gwt/dev/jjs/ast/JField.java
+++ b/dev/core/src/com/google/gwt/dev/jjs/ast/JField.java
@@ -52,10 +52,6 @@
   private String exportName;
   private boolean noExport = false;
 
-  public boolean isNoExport() {
-    return noExport;
-  }
-
   public void setNoExport(boolean noExport) {
     this.noExport = noExport;
   }
@@ -68,6 +64,10 @@
     return exportName;
   }
 
+  public boolean isExported() {
+    return exportName != null && !noExport;
+  }
+
   private static class ExternalSerializedForm implements Serializable {
 
     private final JDeclaredType enclosingType;
diff --git a/dev/core/src/com/google/gwt/dev/jjs/ast/JMethod.java b/dev/core/src/com/google/gwt/dev/jjs/ast/JMethod.java
index aed3155..26faa37 100644
--- a/dev/core/src/com/google/gwt/dev/jjs/ast/JMethod.java
+++ b/dev/core/src/com/google/gwt/dev/jjs/ast/JMethod.java
@@ -68,6 +68,10 @@
     return exportName;
   }
 
+  public boolean isExported() {
+    return exportName != null && !noExport;
+  }
+
   public void setJsProperty(boolean jsProperty) {
     this.jsProperty = jsProperty;
   }
diff --git a/dev/core/src/com/google/gwt/dev/jjs/ast/JTypeOracle.java b/dev/core/src/com/google/gwt/dev/jjs/ast/JTypeOracle.java
index 5e42e85..620e408 100644
--- a/dev/core/src/com/google/gwt/dev/jjs/ast/JTypeOracle.java
+++ b/dev/core/src/com/google/gwt/dev/jjs/ast/JTypeOracle.java
@@ -256,11 +256,11 @@
   }
 
   public boolean isExportedField(JField field) {
-    return isJsInteropEnabled() && field.getExportName() != null && !field.isNoExport();
+    return isJsInteropEnabled() && field.isExported();
   }
 
   public boolean isExportedMethod(JMethod method) {
-    return isJsInteropEnabled() && method.getExportName() != null && !method.isNoExport();
+    return isJsInteropEnabled() && method.isExported();
   }
 
   public boolean isJsInteropEnabled() {
@@ -477,11 +477,6 @@
   private final Map<String, String> jsoByInterface = Maps.newHashMap();
 
   /**
-   * A set of all JsTypes.
-   */
-  private final Set<JInterfaceType> jsInterfaces = Sets.newIdentityHashSet();
-
-  /**
    * A mapping from the type name to the actual type instance.
    */
   private Map<String, JReferenceType> referenceTypesByName = Maps.newHashMap();
@@ -781,15 +776,7 @@
     recordImmediateTypeRelations(moduleDeclaredTypes);
     computeExtendedTypeRelations();
 
-    jsInterfaces.clear();
-
     for (JDeclaredType type : declaredTypes) {
-
-      if (type instanceof JInterfaceType) {
-        if (((JInterfaceType) type).isJsType()) {
-          jsInterfaces.add((JInterfaceType) type);
-        }
-      }
       // first time through, record all exported methods
       for (JMethod method : type.getMethods()) {
         if (isExportedMethod(method)) {
diff --git a/dev/core/src/com/google/gwt/dev/jjs/impl/UnifyAst.java b/dev/core/src/com/google/gwt/dev/jjs/impl/UnifyAst.java
index 6191be3..d7da42e 100644
--- a/dev/core/src/com/google/gwt/dev/jjs/impl/UnifyAst.java
+++ b/dev/core/src/com/google/gwt/dev/jjs/impl/UnifyAst.java
@@ -767,7 +767,7 @@
       }
 
       rootTypeBinaryNames.add(rootType.getName());
-      if (jsInteropEnabled && (isJsType(rootType) || hasAnyExports(rootType))) {
+      if (jsInteropEnabled && (rootType.hasAnyExports() || rootType.isOrExtendsJsType())) {
         fullFlowIntoType(rootType);
       }
     }
@@ -963,31 +963,12 @@
       if (t instanceof JClassType && requiresDevirtualization(t)) {
         instantiate(t);
       }
-      if (hasAnyExports(t) || isJsType(t)) {
+      if (jsInteropEnabled && (t.hasAnyExports() || t.isOrExtendsJsType())) {
         instantiate(t);
       }
     }
   }
 
-  private boolean hasAnyExports(JDeclaredType t) {
-    if (!jsInteropEnabled) {
-      return false;
-    }
-
-    for (JMethod method : t.getMethods()) {
-      if (program.typeOracle.isExportedMethod(method)) {
-        return true;
-      }
-    }
-
-    for (JField field : t.getFields()) {
-      if (program.typeOracle.isExportedField(field)) {
-        return true;
-      }
-    }
-    return false;
-  }
-
   private boolean canAccessSuperMethod(JDeclaredType type, JMethod method) {
     if (method.isPrivate()) {
       return false;
@@ -1311,59 +1292,60 @@
     if (program.isReferenceOnly(type) && !requiresDevirtualization(type)) {
       return;
     }
+    if (instantiatedTypes.contains(type)) {
+      return;
+    }
     if (type.isExternal()) {
       assert errorsFound;
       return;
     }
 
-    if (!instantiatedTypes.contains(type)) {
-      instantiatedTypes.add(type);
-      if (type.getSuperClass() != null) {
-        instantiate(translate(type.getSuperClass()));
-      }
-      for (JInterfaceType intf : type.getImplements()) {
-        instantiate(translate(intf));
-      }
-      staticInitialize(type);
-      boolean isJsType = isJsType(type);
+    instantiatedTypes.add(type);
+    if (type.getSuperClass() != null) {
+      instantiate(translate(type.getSuperClass()));
+    }
+    for (JInterfaceType intf : type.getImplements()) {
+      instantiate(translate(intf));
+    }
+    staticInitialize(type);
+    boolean isJsType = jsInteropEnabled && type.isOrExtendsJsType();
 
-      if (!type.isAbstract()) {
-        // this is a concrete type, add delegation methods for any unimplemented defender methods
-        maybeImplementDefenderMethods(type);
-      }
+    if (!type.isAbstract()) {
+      // this is a concrete type, add delegation methods for any unimplemented defender methods
+      maybeImplementDefenderMethods(type);
+    }
 
-      // Flow into any reachable virtual methods.
-      for (JMethod method : type.getMethods()) {
-        if (method.canBePolymorphic()) {
-          if (isJsType) {
-            // Fake a call into the method to keep it around
-            flowInto(method);
-            continue;
-          }
-          String signature = method.getSignature();
-          if (virtualMethodsLive.contains(signature)) {
-            assert !virtualMethodsPending.containsKey(signature);
-            flowInto(method);
-          } else {
-            List<JMethod> pending = virtualMethodsPending.get(signature);
-            if (pending == null) {
-              pending = Lists.create(method);
-            } else {
-              pending = Lists.add(pending, method);
-            }
-            virtualMethodsPending.put(signature, pending);
-          }
-        } else if (program.typeOracle.isExportedMethod(method) &&
-            (method.isStatic() || method.isConstructor())) {
-          // rescue any @JsExport methods
+    // Flow into any reachable virtual methods.
+    for (JMethod method : type.getMethods()) {
+      if (method.canBePolymorphic()) {
+        if (isJsType) {
+          // Fake a call into the method to keep it around
           flowInto(method);
+          continue;
         }
+        String signature = method.getSignature();
+        if (virtualMethodsLive.contains(signature)) {
+          assert !virtualMethodsPending.containsKey(signature);
+          flowInto(method);
+        } else {
+          List<JMethod> pending = virtualMethodsPending.get(signature);
+          if (pending == null) {
+            pending = Lists.create(method);
+          } else {
+            pending = Lists.add(pending, method);
+          }
+          virtualMethodsPending.put(signature, pending);
+        }
+      } else if (program.typeOracle.isExportedMethod(method)
+          && (method.isStatic() || method.isConstructor())) {
+        // rescue any @JsExport methods
+        flowInto(method);
       }
+    }
 
-      for (JField field : type.getFields()) {
-        if (field.isStatic() && program.typeOracle.isExportedField(field)) {
-          flowInto(field);
-        }
+    for (JField field : type.getFields()) {
+      if (field.isStatic() && program.typeOracle.isExportedField(field)) {
+        flowInto(field);
       }
     }
   }
@@ -1434,22 +1416,6 @@
     return type == program.getJavaScriptObject() || isJso(type.getSuperClass());
   }
 
-  private boolean isJsType(JDeclaredType intf) {
-    if (!jsInteropEnabled) {
-      return false;
-    }
-
-    if (intf.isJsType()) {
-      return true;
-    }
-    for (JInterfaceType subIntf : intf.getImplements()) {
-      if (isJsType(subIntf)) {
-        return true;
-      }
-    }
-    return false;
-  }
-
   /**
    * Main loop: run through the queue doing deferred resolution. We could have
    * made this entirely recursive, but a work queue uses much less max stack.
diff --git a/dev/core/test/com/google/gwt/dev/javac/MockCompilationUnit.java b/dev/core/test/com/google/gwt/dev/javac/MockCompilationUnit.java
index c22303b..75f65c9 100644
--- a/dev/core/test/com/google/gwt/dev/javac/MockCompilationUnit.java
+++ b/dev/core/test/com/google/gwt/dev/javac/MockCompilationUnit.java
@@ -122,6 +122,11 @@
   }
 
   @Override
+  boolean hasJsInteropRootType() {
+    return false;
+  }
+
+  @Override
   ContentId getContentId() {
     return contentId;
   }
diff --git a/user/test/com/google/gwt/core/client/interop/JsExportTest.java b/user/test/com/google/gwt/core/client/interop/JsExportTest.java
index 57c6475..afaf108 100644
--- a/user/test/com/google/gwt/core/client/interop/JsExportTest.java
+++ b/user/test/com/google/gwt/core/client/interop/JsExportTest.java
@@ -55,6 +55,16 @@
     assertTrue(MyClassExportsMethod.calledFromFoo);
   }
 
+  public void testMethodExport_notReferencedFromJava() {
+    // Exported by MyClassExportsMethodWithoutReference which is not referenced by Java. This
+    // ensures that we correctly collect root types.
+    assertEquals(42, onlyCalledFromJs());
+  }
+
+  private native int onlyCalledFromJs() /*-{
+    return $wnd.onlyCalledFromJs();
+  }-*/;
+
   public void testClinit() {
     ScriptInjector.fromString("new $wnd.MyClassExportsMethodWithClinit();").inject();
     assertEquals(23, MyClassExportsMethodWithClinit.magicNumber);
diff --git a/user/test/com/google/gwt/core/client/interop/MyClassExportsMethodWithoutReference.java b/user/test/com/google/gwt/core/client/interop/MyClassExportsMethodWithoutReference.java
new file mode 100644
index 0000000..27ab623
--- /dev/null
+++ b/user/test/com/google/gwt/core/client/interop/MyClassExportsMethodWithoutReference.java
@@ -0,0 +1,28 @@
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.google.gwt.core.client.interop;
+
+import com.google.gwt.core.client.js.JsExport;
+
+/**
+ * A test class exports a method but isn't referenced from any Java code.
+ */
+public class MyClassExportsMethodWithoutReference {
+  @JsExport("onlyCalledFromJs")
+  public static int callMe() {
+    return 42;
+  }
+}