Insert instead of assign to the dest node set, since we use the dest node set
repeatedly.

llvm-svn: 90952
diff --git a/clang/lib/Analysis/GRExprEngine.cpp b/clang/lib/Analysis/GRExprEngine.cpp
index 6104781..dc317cf 100644
--- a/clang/lib/Analysis/GRExprEngine.cpp
+++ b/clang/lib/Analysis/GRExprEngine.cpp
@@ -1688,7 +1688,7 @@
 
     // If the callee is processed by a checker, skip the rest logic.
     if (CheckerEvalCall(CE, DstChecker, *DI))
-      DstTmp3 = DstChecker;
+      DstTmp3.insert(DstChecker);
     else {
       for (ExplodedNodeSet::iterator DI_Checker = DstChecker.begin(),
             DE_Checker = DstChecker.end();