Added special handling for UninitializedVals for the transfer function logic
for pointer dereferences.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@47340 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Analysis/GRExprEngine.cpp b/Analysis/GRExprEngine.cpp
index d1a0d4c..ef3664e 100644
--- a/Analysis/GRExprEngine.cpp
+++ b/Analysis/GRExprEngine.cpp
@@ -642,6 +642,17 @@
         const RValue& V = GetValue(St, U->getSubExpr());        
         const LValue& L1 = cast<LValue>(V);
         
+        if (isa<UninitializedVal>(L1)) {
+          NodeTy* N = Builder->generateNode(U, St, N1);
+          
+          if (N) {
+            N->markAsSink();
+            UninitDeref.insert(N);            
+          }
+          
+          return;
+        }
+        
         // After a dereference, one of two possible situations arise:
         //  (1) A crash, because the pointer was NULL.
         //  (2) The pointer is not NULL, and the dereference works.
@@ -776,6 +787,11 @@
             break;
           }
           
+          if (isa<UninitializedVal>(V2)) {
+            Nodify(Dst, B, N2, SetValue(SetValue(St, B, V2), L1, V2));
+            break;
+          }
+          
           RValue Result = cast<NonLValue>(UnknownVal());
           
           if (Op >= BinaryOperator::AndAssign)
@@ -1232,6 +1248,7 @@
     
     if (GraphPrintCheckerState->isImplicitNullDeref(N) ||
         GraphPrintCheckerState->isExplicitNullDeref(N) ||
+        GraphPrintCheckerState->isUninitDeref(N) ||
         GraphPrintCheckerState->isUninitStore(N) ||
         GraphPrintCheckerState->isUninitControlFlow(N))
       return "color=\"red\",style=\"filled\"";
@@ -1268,6 +1285,9 @@
         else if (GraphPrintCheckerState->isExplicitNullDeref(N)) {
           Out << "\\|Explicit-Null Dereference.\\l";
         }
+        else if (GraphPrintCheckerState->isUninitDeref(N)) {
+          Out << "\\|Dereference of uninitialied value.\\l";
+        }
         else if (GraphPrintCheckerState->isUninitStore(N)) {
           Out << "\\|Store to Uninitialized LValue.";
         }