Add back a condition accidentially removed in r184470.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@184496 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index deb1ba1..16b12ea 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -608,7 +608,7 @@
     return false;
 
   VariadicCallType CallType;
-  if (!Proto) {
+  if (!Proto || !Proto->isVariadic()) {
     CallType = VariadicDoesNotApply;
   } else if (Ty->isBlockPointerType()) {
     CallType = VariadicBlock;