Update aosp/master clang for rebase to r233350

Change-Id: I12d4823f10bc9e445b8b86e7721b71f98d1df442
diff --git a/lib/Sema/SemaAttr.cpp b/lib/Sema/SemaAttr.cpp
index e3b66bf..5a29bad 100644
--- a/lib/Sema/SemaAttr.cpp
+++ b/lib/Sema/SemaAttr.cpp
@@ -422,6 +422,9 @@
   if (Action & PSK_Pop && Stack->Stack.empty())
     Diag(PragmaLocation, diag::warn_pragma_pop_failed) << PragmaName
         << "stack empty";
+  if (SegmentName &&
+      !checkSectionName(SegmentName->getLocStart(), SegmentName->getString()))
+    return;
   Stack->Act(PragmaLocation, Action, StackSlotLabel, SegmentName);
 }