diff --git a/lib/Analysis/GRExprEngine.cpp b/lib/Analysis/GRExprEngine.cpp
index f0c0d8d..a31c435 100644
--- a/lib/Analysis/GRExprEngine.cpp
+++ b/lib/Analysis/GRExprEngine.cpp
@@ -202,10 +202,15 @@
     
     ScopedDecl *SD = const_cast<ScopedDecl*>(I->first);
     if (VarDecl* VD = dyn_cast<VarDecl>(SD)) {
-      if (VD->hasGlobalStorage() || isa<ParmVarDecl>(VD)) {
-        RVal X = RVal::GetSymbolValue(SymMgr, VD);
-        StateMgr.SetRVal(StateImpl, lval::DeclVal(VD), X);
-      }
+      // Initialize globals and parameters to symbolic values.
+      // Initialize local variables to undefined.
+      RVal X = (VD->hasGlobalStorage() || isa<ParmVarDecl>(VD) ||
+                isa<ImplicitParamDecl>(VD))
+             ? RVal::GetSymbolValue(SymMgr, VD)
+             : UndefinedVal();
+      
+      StateMgr.SetRVal(StateImpl, lval::DeclVal(VD), X);
+      
     } else if (ImplicitParamDecl *IPD = dyn_cast<ImplicitParamDecl>(SD)) {
         RVal X = RVal::GetSymbolValue(SymMgr, IPD);
       StateMgr.SetRVal(StateImpl, lval::DeclVal(IPD), X);
diff --git a/lib/Analysis/SymbolManager.cpp b/lib/Analysis/SymbolManager.cpp
index f243fa66..beb4379 100644
--- a/lib/Analysis/SymbolManager.cpp
+++ b/lib/Analysis/SymbolManager.cpp
@@ -18,7 +18,8 @@
 
 SymbolID SymbolManager::getSymbol(VarDecl* D) {
 
-  assert (isa<ParmVarDecl>(D) || D->hasGlobalStorage());
+  assert (isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D) || 
+          D->hasGlobalStorage());
   
   llvm::FoldingSetNodeID profile;