Index: lib/Sema/SemaType.cpp
===================================================================
--- lib/Sema/SemaType.cpp
+++ lib/Sema/SemaType.cpp
@@ -7350,6 +7350,9 @@
       (D.getContext() == DeclaratorContext::MemberContext &&
        (!IsPointee &&
         D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static)) ||
+      // Do not deduce if we are in type alias because it doesn't define any
+      // object.
+      (D.getContext() == DeclaratorContext::AliasDeclContext) ||
       // Do not deduce addr space for types used to define a typedef and the
       // typedef itself, except the pointee type of a pointer type which is used
       // to define the typedef.
Index: test/SemaOpenCLCXX/address-space-deduction.cl
===================================================================
--- test/SemaOpenCLCXX/address-space-deduction.cl
+++ test/SemaOpenCLCXX/address-space-deduction.cl
@@ -23,3 +23,13 @@
   int foo[10];
   xxx(&foo[0]);
 }
+
+struct c1 {};
+
+// We don't deduce addr space in type alias.
+//CHECK: TypeAliasDecl {{.*}} referenced alias_c1 'c1'
+using alias_c1 = c1;
+
+struct c2 {
+  alias_c1 y;
+};