1 files changed, 5 insertions, 2 deletions
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 3ead6ec984f..5fd65f53f44 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -3244,9 +3244,12 @@ static bool CheckExtensionTraitOperandType(Sema &S, QualType T,
     return false;
   }
 
-  // Allow sizeof(void)/alignof(void) as an extension.
+  // Allow sizeof(void)/alignof(void) as an extension, unless in OpenCL where
+  // this is an error (OpenCL v1.1 s6.3.k)
   if (T->isVoidType()) {
-    S.Diag(Loc, diag::ext_sizeof_alignof_void_type) << TraitKind << ArgRange;
+    unsigned DiagID = S.LangOpts.OpenCL ? diag::err_opencl_sizeof_alignof_type
+                                        : diag::ext_sizeof_alignof_void_type;
+    S.Diag(Loc, DiagID) << TraitKind << ArgRange;
     return false;
   }