Added GRStateManager::scanReachableSymbols(), a method which scans the reachable
symbols from an SVal.

- Fixed a bug in EnvironmentManager::RemoveDeadBindings() where it did not mark
  live all the symbols reachable from a live block-level expression.

- Fixed a bug in the retain/release checker where it did not stop tracking
  symbols that 'escaped' via compound literals being assigned to something the
  BasicStoreManager didn't reason about.

llvm-svn: 64534
diff --git a/clang/lib/Analysis/SymbolManager.cpp b/clang/lib/Analysis/SymbolManager.cpp
index 1672af8..f1c1cc0 100644
--- a/clang/lib/Analysis/SymbolManager.cpp
+++ b/clang/lib/Analysis/SymbolManager.cpp
@@ -99,4 +99,5 @@
   // the analyzed function/method.
   return isa<SymbolRegionRValue>(SymMgr.getSymbolData(sym));
 }
-  
+
+SymbolVisitor::~SymbolVisitor() {}