Add comment indicating that we intentionally don't add the noreturn
attribute to a FunctionDecl.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@99662 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index a81ad76..b304112 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -490,6 +490,9 @@
 }
 
 static void HandleNoReturnAttr(Decl *d, const AttributeList &Attr, Sema &S) {
+  // NOTE: We don't add the attribute to a FunctionDecl because the noreturn
+  //  trait will be part of the function's type.
+
   // Don't apply as a decl attribute to ValueDecl.
   // FIXME: probably ought to diagnose this.
   if (isa<ValueDecl>(d))