[C++11] Use 'nullptr'. Analysis edition.

llvm-svn: 209191
diff --git a/clang/lib/Analysis/ReachableCode.cpp b/clang/lib/Analysis/ReachableCode.cpp
index 8be1af7..64be902 100644
--- a/clang/lib/Analysis/ReachableCode.cpp
+++ b/clang/lib/Analysis/ReachableCode.cpp
@@ -402,7 +402,7 @@
     }
   }
 
-  return 0;
+  return nullptr;
 }
 
 static int SrcCmp(const std::pair<const CFGBlock *, const Stmt *> *p1,
@@ -606,7 +606,7 @@
 
 unsigned ScanReachableFromBlock(const CFGBlock *Start,
                                 llvm::BitVector &Reachable) {
-  return scanFromBlock(Start, Reachable, /* SourceManager* */ 0, false);
+  return scanFromBlock(Start, Reachable, /* SourceManager* */ nullptr, false);
 }
 
 void FindUnreachableCode(AnalysisDeclContext &AC, Preprocessor &PP,