diff --git a/Eigen/src/Core/GenericPacketMath.h b/Eigen/src/Core/GenericPacketMath.h
index 0e7dd29ed0..6872f5e530 100644
--- a/Eigen/src/Core/GenericPacketMath.h
+++ b/Eigen/src/Core/GenericPacketMath.h
@@ -43,7 +43,7 @@ struct default_packet_traits
 {
   enum {
     HasHalfPacket = 0,
-    
+
     HasAdd    = 1,
     HasSub    = 1,
     HasMul    = 1,
@@ -76,7 +76,7 @@ struct default_packet_traits
     HasTanh    = 0,
     HasLGamma = 0,
     HasErf = 0,
-    HasErfc = 0
+    HasErfc = 0,
 
     HasRound  = 0,
     HasFloor  = 0,
diff --git a/Eigen/src/Core/SpecialFunctions.h b/Eigen/src/Core/SpecialFunctions.h
index d481f2e068..ae8f0105a6 100644
--- a/Eigen/src/Core/SpecialFunctions.h
+++ b/Eigen/src/Core/SpecialFunctions.h
@@ -1,7 +1,6 @@
 // This file is part of Eigen, a lightweight C++ template library
 // for linear algebra.
 //
-// Copyright (C) 2006-2010 Benoit Jacob <jacob.benoit.1@gmail.com>
 // Copyright (C) 2015 Eugene Brevdo <ebrevdo@gmail.com>
 //
 // This Source Code Form is subject to the terms of the Mozilla
@@ -45,14 +44,13 @@ template <> EIGEN_DEVICE_FUNC EIGEN_STRONG_INLINE double __erfc<double>(double x
 }  // end namespace internal
 
 /****************************************************************************
- * Implementations                                                           *
+ * Implementations                                                          *
  ****************************************************************************/
 
 namespace internal {
 
 /****************************************************************************
- * Implementation of
- * lgamma                                                  *
+ * Implementation of lgamma                                                 *
  ****************************************************************************/
 
 template<typename Scalar>
@@ -72,8 +70,7 @@ struct lgamma_retval
 };
 
 /****************************************************************************
- * Implementation of
- * erf                                                  *
+ * Implementation of erf                                                    *
  ****************************************************************************/
 
 template<typename Scalar>
@@ -92,8 +89,8 @@ struct erf_retval
   typedef Scalar type;
 };
 
-/****************************************************************************
-* Implementation of erfc                                                  *
+/***************************************************************************
+* Implementation of erfc                                                   *
 ****************************************************************************/
 
 template<typename Scalar>
diff --git a/Eigen/src/Core/util/ForwardDeclarations.h b/Eigen/src/Core/util/ForwardDeclarations.h
index 27c7907fcf..483af876fb 100644
--- a/Eigen/src/Core/util/ForwardDeclarations.h
+++ b/Eigen/src/Core/util/ForwardDeclarations.h
@@ -294,12 +294,6 @@ struct stem_function
 };
 }
 
-// SpecialFunctions forward declarations
-namespace internal {
-template <typename Scalar> EIGEN_STRONG_INLINE EIGEN_DEVICE_FUNC Scalar __lgamma(Scalar x);
-template <typename Scalar> EIGEN_STRONG_INLINE EIGEN_DEVICE_FUNC Scalar __erf(Scalar x);
-template <typename Scalar> EIGEN_STRONG_INLINE EIGEN_DEVICE_FUNC Scalar __erfc(Scalar x);
-
 } // end namespace Eigen
 
 #endif // EIGEN_FORWARDDECLARATIONS_H
diff --git a/test/packetmath.cpp b/test/packetmath.cpp
index 304fab5dec..c34b6f3f12 100644
--- a/test/packetmath.cpp
+++ b/test/packetmath.cpp
@@ -355,19 +355,19 @@ template<typename Scalar> void packetmath_real()
     data1[0] = std::numeric_limits<Scalar>::quiet_NaN();
     packet_helper<internal::packet_traits<Scalar>::HasLGamma,Packet> h;
     h.store(data2, internal::plgamma(h.load(data1)));
-    VERIFY(std::isnan(data2[0]));
+    VERIFY((numext::isnan)(data2[0]));
   }
   {
     data1[0] = std::numeric_limits<Scalar>::quiet_NaN();
     packet_helper<internal::packet_traits<Scalar>::HasErf,Packet> h;
     h.store(data2, internal::perf(h.load(data1)));
-    VERIFY(std::isnan(data2[0]));
+    VERIFY((numext::isnan)(data2[0]));
   }
   {
     data1[0] = std::numeric_limits<Scalar>::quiet_NaN();
     packet_helper<internal::packet_traits<Scalar>::HasErfc,Packet> h;
     h.store(data2, internal::perfc(h.load(data1)));
-    VERIFY(std::isnan(data2[0]));
+    VERIFY((numext::isnan)(data2[0]));
   }
 
   for (int i=0; i<size; ++i)
@@ -375,6 +375,8 @@ template<typename Scalar> void packetmath_real()
     data1[i] = internal::random<Scalar>(0,1) * std::pow(Scalar(10), internal::random<Scalar>(-6,6));
     data2[i] = internal::random<Scalar>(0,1) * std::pow(Scalar(10), internal::random<Scalar>(-6,6));
   }
+
+#if __cplusplus > 199711L
   if(internal::random<float>(0,1)<0.1)
     data1[internal::random<int>(0, PacketSize)] = 0;
   CHECK_CWISE1_IF(PacketTraits::HasSqrt, std::sqrt, internal::psqrt);
@@ -382,6 +384,7 @@ template<typename Scalar> void packetmath_real()
   CHECK_CWISE1_IF(internal::packet_traits<Scalar>::HasLGamma, std::lgamma, internal::plgamma);
   CHECK_CWISE1_IF(internal::packet_traits<Scalar>::HasErf, std::erf, internal::perf);
   CHECK_CWISE1_IF(internal::packet_traits<Scalar>::HasErfc, std::erfc, internal::perfc);
+#endif
 
   if(PacketTraits::HasLog && PacketTraits::size>=2)
   {