diff --git a/Eigen/src/Core/arch/AltiVec/PacketMath.h b/Eigen/src/Core/arch/AltiVec/PacketMath.h
index 4b770d036..7ee290a29 100755
--- a/Eigen/src/Core/arch/AltiVec/PacketMath.h
+++ b/Eigen/src/Core/arch/AltiVec/PacketMath.h
@@ -83,15 +83,6 @@ static Packet4i p4i_COUNTDOWN = { 0, 1, 2, 3 };
 static Packet16uc p16uc_REVERSE32 = { 12,13,14,15, 8,9,10,11, 4,5,6,7, 0,1,2,3 };
 static Packet16uc p16uc_DUPLICATE32_HI = { 0,1,2,3, 0,1,2,3, 4,5,6,7, 4,5,6,7 };
 
-// Mask alignment
-#ifdef __PPC64__
-#define _EIGEN_MASK_ALIGNMENT	0xfffffffffffffff0
-#else
-#define _EIGEN_MASK_ALIGNMENT	0xfffffff0
-#endif
-
-#define _EIGEN_ALIGNED_PTR(x)	((std::ptrdiff_t)(x) & _EIGEN_MASK_ALIGNMENT)
-
 // Handle endianness properly while loading constants
 // Define global static constants:
 #ifdef _BIG_ENDIAN
@@ -249,42 +240,38 @@ inline std::ostream & operator <<(std::ostream & s, const Packet4ui & v)
 // Need to define them first or we get specialization after instantiation errors
 template<> EIGEN_STRONG_INLINE Packet4f pload<Packet4f>(const float* from)
 {
+  // some versions of GCC throw "unused-but-set-parameter".
+  // ignoring these warnings for now.
+  EIGEN_UNUSED_VARIABLE(from);
   EIGEN_DEBUG_ALIGNED_LOAD
-#ifdef __VSX__
-  return vec_vsx_ld(0, from);
-#else
   return vec_ld(0, from);
-#endif
 }
 
 template<> EIGEN_STRONG_INLINE Packet4i pload<Packet4i>(const int*     from)
 {
+  // some versions of GCC throw "unused-but-set-parameter".
+  // ignoring these warnings for now.
+  EIGEN_UNUSED_VARIABLE(from);
   EIGEN_DEBUG_ALIGNED_LOAD
-#ifdef __VSX__
-  return vec_vsx_ld(0, from);
-#else
   return vec_ld(0, from);
-#endif
 }
 
 template<> EIGEN_STRONG_INLINE void pstore<float>(float*   to, const Packet4f& from)
 {
+  // some versions of GCC throw "unused-but-set-parameter" (float *to).
+  // ignoring these warnings for now.
+  EIGEN_UNUSED_VARIABLE(to);
   EIGEN_DEBUG_ALIGNED_STORE
-#ifdef __VSX__
-  vec_vsx_st(from, 0, to);
-#else
   vec_st(from, 0, to);
-#endif
 }
 
 template<> EIGEN_STRONG_INLINE void pstore<int>(int*       to, const Packet4i& from)
 {
+  // some versions of GCC throw "unused-but-set-parameter" (float *to).
+  // ignoring these warnings for now.
+  EIGEN_UNUSED_VARIABLE(to);
   EIGEN_DEBUG_ALIGNED_STORE
-#ifdef __VSX__
-  vec_vsx_st(from, 0, to);
-#else
   vec_st(from, 0, to);
-#endif
 }
 
 template<> EIGEN_STRONG_INLINE Packet4f pset1<Packet4f>(const float&  from) {
@@ -452,7 +439,7 @@ template<> EIGEN_STRONG_INLINE Packet4f pandnot<Packet4f>(const Packet4f& a, con
 template<> EIGEN_STRONG_INLINE Packet4i pandnot<Packet4i>(const Packet4i& a, const Packet4i& b) { return vec_and(a, vec_nor(b, b)); }
 
 template<> EIGEN_STRONG_INLINE Packet4f pselect(const Packet4f& mask, const Packet4f& a, const Packet4f& b) {
-  return vec_sel(b, a, mask);
+  return vec_sel(b, a, reinterpret_cast<Packet4ui>(mask));
 }
 
 template<> EIGEN_STRONG_INLINE Packet4f pround<Packet4f>(const Packet4f& a) { return vec_round(a); }
@@ -487,12 +474,12 @@ template<> EIGEN_STRONG_INLINE Packet4i ploadu<Packet4i>(const int* from)
 template<> EIGEN_STRONG_INLINE Packet4i ploadu<Packet4i>(const int* from)
 {
   EIGEN_DEBUG_UNALIGNED_LOAD
-  return (Packet4i) vec_vsx_ld((long)from & 15, (const int*) _EIGEN_ALIGNED_PTR(from));
+  return vec_vsx_ld(0, from);
 }
 template<> EIGEN_STRONG_INLINE Packet4f ploadu<Packet4f>(const float* from)
 {
   EIGEN_DEBUG_UNALIGNED_LOAD
-  return (Packet4f) vec_vsx_ld((long)from & 15, (const float*) _EIGEN_ALIGNED_PTR(from));
+  return vec_vsx_ld(0, from);
 }
 #endif
 
@@ -552,13 +539,13 @@ template<> EIGEN_STRONG_INLINE void pstoreu<int>(int*      to, const Packet4i& f
 // We also need to redefine little endian loading of Packet4i/Packet4f using VSX
 template<> EIGEN_STRONG_INLINE void pstoreu<int>(int*       to, const Packet4i& from)
 {
-  EIGEN_DEBUG_ALIGNED_STORE
-  vec_vsx_st(from, (long)to & 15, (int*) _EIGEN_ALIGNED_PTR(to));
+  EIGEN_DEBUG_UNALIGNED_STORE
+  vec_vsx_st(from, 0, to);
 }
 template<> EIGEN_STRONG_INLINE void pstoreu<float>(float*   to, const Packet4f& from)
 {
-  EIGEN_DEBUG_ALIGNED_STORE
-  vec_vsx_st(from, (long)to & 15, (float*) _EIGEN_ALIGNED_PTR(to));
+  EIGEN_DEBUG_UNALIGNED_STORE
+  vec_vsx_st(from, 0, to);
 }
 #endif
 
@@ -949,21 +936,13 @@ inline std::ostream & operator <<(std::ostream & s, const Packet2d & v)
 template<> EIGEN_STRONG_INLINE Packet2d pload<Packet2d>(const double* from)
 {
   EIGEN_DEBUG_ALIGNED_LOAD
-#ifdef __VSX__
-  return vec_vsx_ld(0, from);
-#else
-  return vec_ld(0, from);
-#endif
+  return vec_xl(0, const_cast<double *>(from)); // cast needed by Clang
 }
 
 template<> EIGEN_STRONG_INLINE void pstore<double>(double*   to, const Packet2d& from)
 {
   EIGEN_DEBUG_ALIGNED_STORE
-#ifdef __VSX__
-  vec_vsx_st(from, 0, to);
-#else
-  vec_st(from, 0, to);
-#endif
+  vec_xst(from, 0, to);
 }
 
 template<> EIGEN_STRONG_INLINE Packet2d pset1<Packet2d>(const double&  from) {
@@ -1030,6 +1009,14 @@ template<> EIGEN_STRONG_INLINE Packet2d pmax<Packet2d>(const Packet2d& a, const
   return ret;
 }
 
+template<> EIGEN_STRONG_INLINE Packet2d pcmp_le(const Packet2d& a, const Packet2d& b) { return reinterpret_cast<Packet2d>(vec_cmple(a,b)); }
+template<> EIGEN_STRONG_INLINE Packet2d pcmp_lt(const Packet2d& a, const Packet2d& b) { return reinterpret_cast<Packet2d>(vec_cmplt(a,b)); }
+template<> EIGEN_STRONG_INLINE Packet2d pcmp_eq(const Packet2d& a, const Packet2d& b) { return reinterpret_cast<Packet2d>(vec_cmpeq(a,b)); }
+template<> EIGEN_STRONG_INLINE Packet2d pcmp_lt_or_nan(const Packet2d& a, const Packet2d& b) {
+  Packet2d c = reinterpret_cast<Packet2d>(vec_cmpge(a,b));
+  return vec_nor(c,c);
+}
+
 template<> EIGEN_STRONG_INLINE Packet2d pand<Packet2d>(const Packet2d& a, const Packet2d& b) { return vec_and(a, b); }
 
 template<> EIGEN_STRONG_INLINE Packet2d por<Packet2d>(const Packet2d& a, const Packet2d& b) { return vec_or(a, b); }
@@ -1044,8 +1031,8 @@ template<> EIGEN_STRONG_INLINE Packet2d pfloor<Packet2d>(const Packet2d& a) { re
 
 template<> EIGEN_STRONG_INLINE Packet2d ploadu<Packet2d>(const double* from)
 {
-  EIGEN_DEBUG_ALIGNED_LOAD
-  return (Packet2d) vec_vsx_ld((long)from & 15, (const double*) _EIGEN_ALIGNED_PTR(from));
+  EIGEN_DEBUG_UNALIGNED_LOAD
+  return vec_vsx_ld(0, from);
 }
 
 template<> EIGEN_STRONG_INLINE Packet2d ploaddup<Packet2d>(const double*   from)
@@ -1058,8 +1045,8 @@ template<> EIGEN_STRONG_INLINE Packet2d ploaddup<Packet2d>(const double*   from)
 
 template<> EIGEN_STRONG_INLINE void pstoreu<double>(double*  to, const Packet2d& from)
 {
-  EIGEN_DEBUG_ALIGNED_STORE
-  vec_vsx_st((Packet4f)from, (long)to & 15, (float*) _EIGEN_ALIGNED_PTR(to));
+  EIGEN_DEBUG_UNALIGNED_STORE
+  vec_vsx_st(from, 0, to);
 }
 
 template<> EIGEN_STRONG_INLINE void prefetch<double>(const double* addr) { EIGEN_PPC_PREFETCH(addr); }
diff --git a/Eigen/src/Core/util/DisableStupidWarnings.h b/Eigen/src/Core/util/DisableStupidWarnings.h
index 6c7c2d655..4501d3248 100755
--- a/Eigen/src/Core/util/DisableStupidWarnings.h
+++ b/Eigen/src/Core/util/DisableStupidWarnings.h
@@ -44,6 +44,11 @@
   #if __clang_major__ >= 3 && __clang_minor__ >= 5
     #pragma clang diagnostic ignored "-Wabsolute-value"
   #endif
+  #if ( defined(__ALTIVEC__) || defined(__VSX__) ) && __cplusplus < 201103L
+    // warning: generic selections are a C11-specific feature
+    // ignoring warnings thrown at vec_ctf in Altivec/PacketMath.h
+    #pragma clang diagnostic ignored "-Wc11-extensions"
+  #endif
 
 #elif defined __GNUC__