PR4350: Make sure we don't create invalid printf attributes.  This isn't  visible anywhere normally because the printf format checks for  this case, and we don't print out attribute values anywhere.  Original  patch by Roberto Bagnara.
PR4350: Make sure we don't create invalid printf attributes.  This isn't 
visible anywhere normally because the printf format checks for 
this case, and we don't print out attribute values anywhere.  Original 
patch by Roberto Bagnara.



git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@73157 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang