--- a/lib/Analysis/CFG.cpp	Tue Oct 13 17:49:56 2015 +0900
+++ b/lib/Analysis/CFG.cpp	Tue Jan 26 22:53:40 2016 +0900
@@ -69,8 +69,9 @@
 /// and return its position in the terminator instruction's list of
 /// successors.  It is an error to call this with a block that is not a
 /// successor.
-unsigned llvm::GetSuccessorNumber(BasicBlock *BB, BasicBlock *Succ) {
-  TerminatorInst *Term = BB->getTerminator();
+unsigned llvm::GetSuccessorNumber(const BasicBlock *BB,
+    const BasicBlock *Succ) {
+  const TerminatorInst *Term = BB->getTerminator();
 #ifndef NDEBUG
   unsigned e = Term->getNumSuccessors();
 #endif