--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/FoldConstants.java	Tue Jan 19 20:31:40 2016 -0800
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/codegen/FoldConstants.java	Thu Jan 21 16:31:27 2016 +0100
@@ -335,7 +335,7 @@
                 break;
             case SHR:
                 final long result = JSType.toUint32(lhs.getInt32() >>> rhs.getInt32());
-                return LiteralNode.newInstance(token, finish, JSType.isRepresentableAsInt(result) ? (int) result : (double) result);
+                return LiteralNode.newInstance(token, finish, JSType.toNarrowestNumber(result));
             case SAR:
                 return LiteralNode.newInstance(token, finish, lhs.getInt32() >> rhs.getInt32());
             case SHL:

--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/objects/NativeArray.java	Tue Jan 19 20:31:40 2016 -0800
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/objects/NativeArray.java	Thu Jan 21 16:31:27 2016 +0100
@@ -70,7 +70,6 @@
 import jdk.nashorn.internal.runtime.arrays.ArrayLikeIterator;
 import jdk.nashorn.internal.runtime.arrays.ContinuousArrayData;
 import jdk.nashorn.internal.runtime.arrays.IntElements;
-import jdk.nashorn.internal.runtime.arrays.IntOrLongElements;
 import jdk.nashorn.internal.runtime.arrays.IteratorAction;
 import jdk.nashorn.internal.runtime.arrays.NumericElements;
 import jdk.nashorn.internal.runtime.linker.Bootstrap;
@@ -285,7 +284,7 @@
         final long newLen = NativeArray.validLength(newLenDesc.getValue());
 
         // Step 3e - note that we need to convert to int or double as long is not considered a JS number type anymore
-        newLenDesc.setValue(JSType.isRepresentableAsInt(newLen) ? Integer.valueOf((int) newLen) : Double.valueOf((double) newLen));
+        newLenDesc.setValue(JSType.toNarrowestNumber(newLen));
 
         // Step 3f
         // increasing array length - just need to set new length value (and attributes if any) and return
@@ -1043,7 +1042,7 @@
             if (bulkable(sobj) && sobj.getArray().length() + args.length <= JSType.MAX_UINT) {
                 final ArrayData newData = sobj.getArray().push(true, args);
                 sobj.setArray(newData);
-                return newData.length();
+                return JSType.toNarrowestNumber(newData.length());
             }
 
             long len = JSType.toUint32(sobj.getLength());
@@ -1052,7 +1051,7 @@
             }
             sobj.set("length", len, CALLSITE_STRICT);
 
-            return len;
+            return JSType.toNarrowestNumber(len);
         } catch (final ClassCastException | NullPointerException e) {
             throw typeError(Context.getGlobal(), e, "not.an.object", ScriptRuntime.safeToString(self));
         }
@@ -1471,7 +1470,7 @@
         final long newLength = len + items.length;
         sobj.set("length", newLength, CALLSITE_STRICT);
 
-        return newLength;
+        return JSType.toNarrowestNumber(newLength);
     }
 
     /**

--- a/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/runtime/JSType.java	Tue Jan 19 20:31:40 2016 -0800
+++ b/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/runtime/JSType.java	Thu Jan 21 16:31:27 2016 +0100
@@ -791,6 +791,15 @@
         return Double.NaN;
     }
 
+    /**
+     * Convert a long to the narrowest JavaScript Number type. This returns either a
+     * {@link Integer} or {@link Double} depending on the magnitude of {@code l}.
+     * @param l a long value
+     * @return the value converted to Integer or Double
+     */
+    public static Number toNarrowestNumber(final long l) {
+        return isRepresentableAsInt(l) ? Integer.valueOf((int) l) : Double.valueOf((double) l);
+    }
 
     /**
      * JavaScript compliant conversion of Boolean to number
@@ -1727,21 +1736,6 @@
     }
 
     /**
-     * Returns the boxed version of a primitive class
-     * @param clazz the class
-     * @return the boxed type of clazz, or unchanged if not primitive
-     */
-    public static Class<?> getBoxedClass(final Class<?> clazz) {
-        if (clazz == int.class) {
-            return Integer.class;
-        } else if (clazz == double.class) {
-            return Double.class;
-        }
-        assert !clazz.isPrimitive();
-        return clazz;
-    }
-
-    /**
      * Create a method handle constant of the correct primitive type
      * for a constant object
      * @param o object

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/script/basic/JDK-8147845.js	Thu Jan 21 16:31:27 2016 +0100
@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ * 
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ * 
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ * 
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ * 
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * JDK-8147845: Varargs Array functions still leaking longs
+ *
+ * @test
+ * @run
+ */
+
+Assert.assertTrue([].push() === 0);
+Assert.assertTrue([].unshift() === 0);
+Assert.assertTrue(typeof [].push() === 'number');
+Assert.assertTrue(typeof [].unshift() === 'number');
+
+Assert.assertTrue([].push(1, 2, 3) === 3);
+Assert.assertTrue([].unshift(1, 2, 3) === 3);
+Assert.assertTrue(typeof [].push(1, 2, 3) === 'number');
+Assert.assertTrue(typeof [].unshift(1, 2, 3) === 'number');
+
+Assert.assertTrue([].push(1) === 1);
+Assert.assertTrue([].unshift(1) === 1);
+Assert.assertTrue(typeof [].push(1) === 'number');
+Assert.assertTrue(typeof [].unshift(1) === 'number');