Index: include/clang/Basic/DiagnosticSemaKinds.td
===================================================================
--- include/clang/Basic/DiagnosticSemaKinds.td
+++ include/clang/Basic/DiagnosticSemaKinds.td
@@ -8304,6 +8304,9 @@
   "bit-fields are not supported in OpenCL">;
 def err_opencl_vla : Error<
   "variable length arrays are not supported in OpenCL">;
+def err_opencl_scalar_type_rank_greater_than_vector_type : Error<
+    "scalar operand type has greater rank than the type of the vector "
+    "element. (%0 and %1)">;
 def err_bad_kernel_param_type : Error<
   "%0 cannot be used as the type of a kernel parameter">;
 def err_record_with_pointers_kernel_param : Error<
Index: lib/Sema/SemaExpr.cpp
===================================================================
--- lib/Sema/SemaExpr.cpp
+++ lib/Sema/SemaExpr.cpp
@@ -8064,28 +8064,38 @@
 /// rank; for C, Obj-C, and C++ we allow any real scalar conversion except
 /// for float->int.
 ///
+/// OpenCL V2.0 6.2.6.p2:
+/// An error shall occur if any scalar operand type has greater rank
+/// than the type of the vector element.
+///
 /// \param scalar - if non-null, actually perform the conversions
 /// \return true if the operation fails (but without diagnosing the failure)
 static bool tryVectorConvertAndSplat(Sema &S, ExprResult *scalar,
                                      QualType scalarTy,
                                      QualType vectorEltTy,
-                                     QualType vectorTy) {
+                                     QualType vectorTy,
+                                     unsigned &DiagID) {
   // The conversion to apply to the scalar before splatting it,
   // if necessary.
   CastKind scalarCast = CK_Invalid;
   
   if (vectorEltTy->isIntegralType(S.Context)) {
-    if (!scalarTy->isIntegralType(S.Context))
+    if (S.getLangOpts().OpenCL && (scalarTy->isRealFloatingType() ||
+        (scalarTy->isIntegerType() &&
+         S.Context.getIntegerTypeOrder(vectorEltTy, scalarTy) < 0))) {
+      DiagID = diag::err_opencl_scalar_type_rank_greater_than_vector_type;
       return true;
-    if (S.getLangOpts().OpenCL &&
-        S.Context.getIntegerTypeOrder(vectorEltTy, scalarTy) < 0)
+    }
+    if (!scalarTy->isIntegralType(S.Context))
       return true;
     scalarCast = CK_IntegralCast;
   } else if (vectorEltTy->isRealFloatingType()) {
     if (scalarTy->isRealFloatingType()) {
       if (S.getLangOpts().OpenCL &&
-          S.Context.getFloatingTypeOrder(vectorEltTy, scalarTy) < 0)
+          S.Context.getFloatingTypeOrder(vectorEltTy, scalarTy) < 0) {
+        DiagID = diag::err_opencl_scalar_type_rank_greater_than_vector_type;
         return true;
+      }
       scalarCast = CK_FloatingCast;
     }
     else if (scalarTy->isIntegralType(S.Context))
@@ -8331,10 +8341,12 @@
 
   // If there's a vector type and a scalar, try to convert the scalar to
   // the vector element type and splat.
+  unsigned DiagID = diag::err_typecheck_vector_not_convertable;
   if (!RHSVecType) {
     if (isa<ExtVectorType>(LHSVecType)) {
       if (!tryVectorConvertAndSplat(*this, &RHS, RHSType,
-                                    LHSVecType->getElementType(), LHSType))
+                                    LHSVecType->getElementType(), LHSType,
+                                    DiagID))
         return LHSType;
     } else {
       if (!tryGCCVectorConvertAndSplat(*this, &RHS, &LHS))
@@ -8345,7 +8357,7 @@
     if (isa<ExtVectorType>(RHSVecType)) {
       if (!tryVectorConvertAndSplat(*this, (IsCompAssign ? nullptr : &LHS),
                                     LHSType, RHSVecType->getElementType(),
-                                    RHSType))
+                                    RHSType, DiagID))
         return RHSType;
     } else {
       if (LHS.get()->getValueKind() == VK_LValue ||
@@ -8421,7 +8433,7 @@
   }
 
   // Otherwise, use the generic diagnostic.
-  Diag(Loc, diag::err_typecheck_vector_not_convertable)
+  Diag(Loc, DiagID)
     << LHSType << RHSType
     << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
   return QualType();
Index: test/SemaOpenCL/arithmetic-conversions.cl
===================================================================
--- /dev/null
+++ test/SemaOpenCL/arithmetic-conversions.cl
@@ -0,0 +1,23 @@
+// RUN: %clang_cc1 %s -verify -pedantic -fsyntax-only -cl-std=CL1.2
+
+typedef float float2 __attribute__((ext_vector_type(2)));
+typedef long long2 __attribute__((ext_vector_type(2)));
+typedef int int2 __attribute__((ext_vector_type(2)));
+
+kernel void foo1(float2 in, global float2 *out) { *out = in + 0.5;} // expected-error {{scalar operand type has greater rank than the type of the vector element. ('float2' (vector of 2 'float' values) and 'double')}}
+
+kernel void foo2(float2 in, global float2 *out) { *out = 0.5 + in;} // expected-error {{scalar operand type has greater rank than the type of the vector element. ('double' and 'float2' (vector of 2 'float' values))}}
+
+kernel void foo3(float2 in, global float2 *out) { *out = 0.5f + in;}
+
+kernel void foo4(long2 in, global long2 *out) { *out = 5 + in;}
+
+kernel void foo5(float2 in, global float2 *out) {
+    float* f;
+    *out = f + in; // expected-error{{cannot convert between vector and non-scalar values ('float *' and 'float2' (vector of 2 'float' values))}}
+}
+
+kernel void foo6(int2 in, global int2 *out) {
+    int* f;
+    *out = f + in; // expected-error{{cannot convert between vector and non-scalar values ('int *' and 'int2' (vector of 2 'int' values))}}
+}
Index: test/SemaOpenCL/cond.cl
===================================================================
--- test/SemaOpenCL/cond.cl
+++ test/SemaOpenCL/cond.cl
@@ -89,7 +89,7 @@
 
 float2 ntest05(int2 C, int2 X, float Y)
 {
-  return C ? X : Y; // expected-error {{cannot convert between vector values of different size ('int2' (vector of 2 'int' values) and 'float')}}
+  return C ? X : Y; // expected-error {{scalar operand type has greater rank than the type of the vector element. ('int2' (vector of 2 'int' values) and 'float'}}
 }
 
 char2 ntest06(int2 C, char2 X, char2 Y)