diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -4193,7 +4193,9 @@
   case ICK_Lvalue_To_Rvalue: {
     assert(From->getObjectKind() != OK_ObjCProperty);
     ExprResult FromRes = DefaultLvalueConversion(From);
-    assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!");
+    if (FromRes.isInvalid())
+      return ExprError();
+
     From = FromRes.get();
     FromType = From->getType();
     break;
diff --git a/clang/test/SemaOpenCLCXX/half.clcpp b/clang/test/SemaOpenCLCXX/half.clcpp
new file mode 100644
--- /dev/null
+++ b/clang/test/SemaOpenCLCXX/half.clcpp
@@ -0,0 +1,15 @@
+//RUN: %clang_cc1 %s -triple spir -verify -fsyntax-only
+
+#pragma OPENCL EXTENSION cl_khr_fp16 : disable
+
+typedef half half2 __attribute__((ext_vector_type(2)));
+
+half f(half2 h2) { // expected-error{{declaring function return value of type 'half' is not allowed ; did you forget * ?}}
+    return h2.s0; // expected-error{{loading directly from pointer to type '__private half' requires cl_khr_fp16. Use vector data load builtin functions instead}}
+}
+
+#pragma OPENCL EXTENSION cl_khr_fp16 : enable
+
+half f(half2 h2) {
+    return h2.s0;
+}