Index: include/clang/Basic/DiagnosticSemaKinds.td
===================================================================
--- include/clang/Basic/DiagnosticSemaKinds.td
+++ include/clang/Basic/DiagnosticSemaKinds.td
@@ -8156,6 +8156,8 @@
   "feature, not permitted in C++">;
 def err_type_unsupported : Error<
   "%0 is not supported on this target">;
+def err_ocl_type_reserved : Error<
+  "'%0' is a reserved type in OpenCL">;
 def err_nsconsumed_attribute_mismatch : Error<
   "overriding method has mismatched ns_consumed attribute on its"
   " parameter">;
Index: lib/Sema/SemaType.cpp
===================================================================
--- lib/Sema/SemaType.cpp
+++ lib/Sema/SemaType.cpp
@@ -1363,6 +1363,11 @@
           else
             S.Diag(DS.getTypeSpecWidthLoc(), diag::ext_c99_longlong);
         }
+        else if (S.getLangOpts().OpenCL) {
+          // OpenCL v2.0 s6.1.4: 'long long' is a reserved data type.
+          S.Diag(DS.getTypeSpecWidthLoc(), diag::err_ocl_type_reserved)
+            << "long long";
+        }
         break;
       }
     } else {
@@ -1382,6 +1387,11 @@
           else
             S.Diag(DS.getTypeSpecWidthLoc(), diag::ext_c99_longlong);
         }
+        else if (S.getLangOpts().OpenCL) {
+          // OpenCL v2.0 s6.1.4: 'unsigned long long' is a reserved data type.
+          S.Diag(DS.getTypeSpecWidthLoc(), diag::err_ocl_type_reserved)
+            << "unsigned long long";
+        }
         break;
       }
     }
@@ -1399,9 +1409,14 @@
   case DeclSpec::TST_half: Result = Context.HalfTy; break;
   case DeclSpec::TST_float: Result = Context.FloatTy; break;
   case DeclSpec::TST_double:
-    if (DS.getTypeSpecWidth() == DeclSpec::TSW_long)
+    if (DS.getTypeSpecWidth() == DeclSpec::TSW_long) {
       Result = Context.LongDoubleTy;
-    else
+      if (S.getLangOpts().OpenCL) {
+        // OpenCL v2.0 s6.1.4: 'long double' is a reserved data type.
+        S.Diag(DS.getTypeSpecWidthLoc(), diag::err_ocl_type_reserved)
+          << "long double";
+      }
+    } else
       Result = Context.DoubleTy;
     break;
   case DeclSpec::TST_float128:
Index: test/Misc/languageOptsOpenCL.cl
===================================================================
--- test/Misc/languageOptsOpenCL.cl
+++ test/Misc/languageOptsOpenCL.cl
@@ -8,14 +8,12 @@
   int v1[(__alignof(int)== 4) - 1];
   int v2[(sizeof(long) == 8) - 1];
   int v3[(__alignof(long)== 8) - 1];
-  int v4[(sizeof(long long) == 16) - 1];
-  int v5[(__alignof(long long)== 16) - 1];
-  int v6[(sizeof(float) == 4) - 1];
-  int v7[(__alignof(float)== 4) - 1];
+  int v4[(sizeof(float) == 4) - 1];
+  int v5[(__alignof(float)== 4) - 1];
 #pragma OPENCL EXTENSION cl_khr_fp64 : enable
-  int v8[(sizeof(double) == 8) - 1];
-  int v9[(__alignof(double)== 8) - 1];
+  int v6[(sizeof(double) == 8) - 1];
+  int v7[(__alignof(double)== 8) - 1];
 #pragma OPENCL EXTENSION cl_khr_fp16 : enable
-  int v10[(sizeof(half) == 2) - 1];
-  int v11[(__alignof(half) == 2) - 1];
+  int v8[(sizeof(half) == 2) - 1];
+  int v9[(__alignof(half) == 2) - 1];
 }
Index: test/SemaOpenCL/unsupported.cl
===================================================================
--- test/SemaOpenCL/unsupported.cl
+++ test/SemaOpenCL/unsupported.cl
@@ -11,3 +11,10 @@
 void no_logxor(int n) {
   int logxor = n ^^ n; // expected-error {{^^ is a reserved operator in OpenCL}}
 }
+
+#pragma OPENCL EXTENSION cl_khr_fp64 : enable
+
+kernel void no_long_double(global long double *n) {} // expected-error {{'long double' is a reserved type in OpenCL}}
+
+kernel void no_long_long(global long long *n) {} // expected-error {{'long long' is a reserved type in OpenCL}}
+kernel void no_unsigned_long_long(global unsigned long long *n) {} // expected-error {{'unsigned long long' is a reserved type in OpenCL}}