ubsan: Add checking for invalid downcasts. Per [expr.static.cast]p2 and p11,

base-to-derived casts have undefined behavior if the object is not actually an
instance of the derived type.

llvm-svn: 175078

1 files changed, 7 insertions, 1 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index ea5e8733d6f..e85c23e2172 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -1895,7 +1895,13 @@ public:
     /// Must be an object within its lifetime.
     TCK_MemberCall,
     /// Checking the 'this' pointer for a constructor call.
-    TCK_ConstructorCall
+    TCK_ConstructorCall,
+    /// Checking the operand of a static_cast to a derived pointer type. Must be
+    /// null or an object within its lifetime.
+    TCK_DowncastPointer,
+    /// Checking the operand of a static_cast to a derived reference type. Must
+    /// be an object within its lifetime.
+    TCK_DowncastReference
   };
 
   /// \brief Emit a check that \p V is the address of storage of the