diff --git a/include/v8-version.h b/include/v8-version.h
index 69a121c6e95..9ddf825d5ba 100644
--- a/include/v8-version.h
+++ b/include/v8-version.h
@@ -11,7 +11,7 @@
 #define V8_MAJOR_VERSION 5
 #define V8_MINOR_VERSION 0
 #define V8_BUILD_NUMBER 71
-#define V8_PATCH_LEVEL 14
+#define V8_PATCH_LEVEL 15
 
 // Use 1 for candidates and 0 otherwise.
 // (Boolean macro values are not supported by all preprocessors.)
diff --git a/src/crankshaft/hydrogen.cc b/src/crankshaft/hydrogen.cc
index 1eccd38789c..9f3654f774c 100644
--- a/src/crankshaft/hydrogen.cc
+++ b/src/crankshaft/hydrogen.cc
@@ -2050,9 +2050,8 @@ HValue* HGraphBuilder::BuildNumberToString(HValue* object, Type* type) {
   return Pop();
 }
 
-
-HValue* HGraphBuilder::BuildToNumber(HValue* input, Type* input_type) {
-  if (input->type().IsTaggedNumber() || input_type->Is(Type::Number())) {
+HValue* HGraphBuilder::BuildToNumber(HValue* input) {
+  if (input->type().IsTaggedNumber()) {
     return input;
   }
   Callable callable = CodeFactory::ToNumber(isolate());
@@ -11129,10 +11128,10 @@ HValue* HGraphBuilder::BuildBinaryOperation(Token::Value op, HValue* left,
   // Special case for +x here.
   if (op == Token::MUL) {
     if (left->EqualsInteger32Constant(1)) {
-      return BuildToNumber(right, right_type);
+      return BuildToNumber(right);
     }
     if (right->EqualsInteger32Constant(1)) {
-      return BuildToNumber(left, left_type);
+      return BuildToNumber(left);
     }
   }
 
@@ -12360,8 +12359,7 @@ void HOptimizedGraphBuilder::GenerateToNumber(CallRuntime* call) {
   CHECK_ALIVE(VisitForValue(call->arguments()->at(0)));
   Callable callable = CodeFactory::ToNumber(isolate());
   HValue* input = Pop();
-  Type* input_type = Type::Any();
-  HValue* result = BuildToNumber(input, input_type);
+  HValue* result = BuildToNumber(input);
   if (result->HasObservableSideEffects()) {
     if (!ast_context()->IsEffect()) Push(result);
     Add<HSimulate>(call->id(), REMOVABLE_SIMULATE);
diff --git a/src/crankshaft/hydrogen.h b/src/crankshaft/hydrogen.h
index d41b010ad4d..ce0d0df6aaa 100644
--- a/src/crankshaft/hydrogen.h
+++ b/src/crankshaft/hydrogen.h
@@ -1321,7 +1321,7 @@ class HGraphBuilder {
                                    bool is_jsarray);
 
   HValue* BuildNumberToString(HValue* object, Type* type);
-  HValue* BuildToNumber(HValue* input, Type* input_type);
+  HValue* BuildToNumber(HValue* input);
   HValue* BuildToObject(HValue* receiver);
 
   void BuildJSObjectCheck(HValue* receiver,
diff --git a/test/mjsunit/regress/regress-crbug-590989-1.js b/test/mjsunit/regress/regress-crbug-590989-1.js
new file mode 100644
index 00000000000..73118eb20e8
--- /dev/null
+++ b/test/mjsunit/regress/regress-crbug-590989-1.js
@@ -0,0 +1,18 @@
+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax
+
+var o = {}
+var p = {foo: 1.5}
+
+function g(x) { return x.foo === +x.foo; }
+
+assertEquals(false, g(o));
+assertEquals(false, g(o));
+%OptimizeFunctionOnNextCall(g);
+assertEquals(false, g(o));  // Still fine here.
+assertEquals(true, g(p));
+%OptimizeFunctionOnNextCall(g);
+assertEquals(false, g(o));  // Confused by type feedback.
diff --git a/test/mjsunit/regress/regress-crbug-590989-2.js b/test/mjsunit/regress/regress-crbug-590989-2.js
new file mode 100644
index 00000000000..cae1d9db5bd
--- /dev/null
+++ b/test/mjsunit/regress/regress-crbug-590989-2.js
@@ -0,0 +1,12 @@
+// Copyright 2016 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax
+
+function f(x) { return x === +x; }
+
+assertEquals(false, f(undefined));
+assertEquals(false, f(undefined));
+%OptimizeFunctionOnNextCall(f);
+assertEquals(false, f(undefined));  // Interestingly this fails right away.