Index: lib/Sema/SemaOverload.cpp
===================================================================
--- lib/Sema/SemaOverload.cpp
+++ lib/Sema/SemaOverload.cpp
@@ -7659,6 +7659,18 @@
     }
   }
 }
+/// Helper function for adjusting address spaces for the pointer or reference
+/// operands of builtin operators
+static QualType AdjustAddressSpaceForBuiltinOperandType(Sema &S, QualType T) {
+  // For OpenCL all builtin operators should use generic addr space on their
+  // pointer or reference operands.
+  if (S.LangOpts.OpenCL) {
+    return S.Context.getAddrSpaceQualType(S.Context.removeAddrSpaceQualType(T),
+                                          LangAS::opencl_generic);
+  }
+  // FIXME: Generalise to C++.
+  return T;
+}
 
 /// Helper function for AddBuiltinOperatorCandidates() that adds
 /// the volatile- and non-volatile-qualified assignment operators for the
@@ -7670,15 +7682,17 @@
   QualType ParamTypes[2];
 
   // T& operator=(T&, T)
-  ParamTypes[0] = S.Context.getLValueReferenceType(T);
+  ParamTypes[0] = S.Context.getLValueReferenceType(
+      AdjustAddressSpaceForBuiltinOperandType(S, T));
   ParamTypes[1] = T;
   S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
                         /*IsAssignmentOperator=*/true);
 
   if (!S.Context.getCanonicalType(T).isVolatileQualified()) {
     // volatile T& operator=(volatile T&, T)
-    ParamTypes[0]
-      = S.Context.getLValueReferenceType(S.Context.getVolatileType(T));
+    ParamTypes[0] = S.Context.getLValueReferenceType(
+        AdjustAddressSpaceForBuiltinOperandType(S,
+                                                S.Context.getVolatileType(T)));
     ParamTypes[1] = T;
     S.AddBuiltinCandidate(ParamTypes, Args, CandidateSet,
                           /*IsAssignmentOperator=*/true);
Index: test/CodeGenOpenCLCXX/addrspace-operators.cl
===================================================================
--- /dev/null
+++ test/CodeGenOpenCLCXX/addrspace-operators.cl
@@ -0,0 +1,24 @@
+//RUN: %clang_cc1 %s -triple spir -cl-std=c++ -emit-llvm -O0 -o - | FileCheck %s
+
+enum E {
+  a,
+  b,
+};
+
+class C {
+public:
+  void foo(E e) { me = e; }
+  E me;
+};
+
+void bar() {
+  C c;
+  //CHECK: addrspacecast %class.C* %c to %class.C addrspace(4)*
+  //CHECK: call void @_ZNU3AS41C3fooE1E(%class.C addrspace(4)* %{{[0-9]+}}, i32 0)
+  c.foo(a);
+}
+
+//CHECK: define linkonce_odr void @_ZNU3AS41C3fooE1E(%class.C addrspace(4)* %this, i32 %e)
+//CHECK: [[E:%[0-9]+]] = load i32, i32* %e.addr
+//CHECK: %me = getelementptr inbounds %class.C, %class.C addrspace(4)* %this1, i32 0, i32 0
+//CHECK: store i32 [[E]], i32 addrspace(4)* %me