Fix unused variable warning

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70946 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Analysis/BasicStore.cpp

@@ -212,7 +212,7 @@ SVal BasicStoreManager::getLValueElement(const GRState* St,
     case loc::MemRegionKind: {
       const MemRegion *R = cast<loc::MemRegionVal>(BaseL).getRegion();
       
-      if (const ElementRegion *ER = dyn_cast<ElementRegion>(R)) {
+      if (isa<ElementRegion>(R)) {
         // int x;
         // char* y = (char*) &x;
         // 'y' => ElementRegion(0, VarRegion('x'))