diff --git a/lib/Analysis/AnalysisContext.cpp b/lib/Analysis/AnalysisContext.cpp
index ef47ece..da671d6 100644
--- a/lib/Analysis/AnalysisContext.cpp
+++ b/lib/Analysis/AnalysisContext.cpp
@@ -28,10 +28,15 @@
   delete PM;
 }
 
+AnalysisContextManager::~AnalysisContextManager() {
+  for (ContextMap::iterator I = Contexts.begin(), E = Contexts.end(); I!=E; ++I)
+    delete I->second;
+}
+
 Stmt *AnalysisContext::getBody() {
-  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
+  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
     return FD->getBody();
-  else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D))
+  else if (const ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D))
     return MD->getBody();
 
   llvm::llvm_unreachable("unknown code decl");
@@ -70,14 +75,12 @@
   return liveness;
 }
 
-AnalysisContext *AnalysisContextManager::getContext(Decl *D) {
-  iterator I = Contexts.find(D);
-  if (I != Contexts.end())
-    return &(I->second);
-
-  AnalysisContext &Ctx = Contexts[D];
-  Ctx.setDecl(D);
-  return &Ctx;
+AnalysisContext *AnalysisContextManager::getContext(const Decl *D) {
+  AnalysisContext *&AC = Contexts[D];
+  if (!AC)
+    AC = new AnalysisContext(D);
+  
+  return AC;
 }
 
 void LocationContext::Profile(llvm::FoldingSetNodeID &ID, ContextKind k,
diff --git a/lib/Analysis/AnalysisManager.cpp b/lib/Analysis/AnalysisManager.cpp
index 125c00b..f29cd78 100644
--- a/lib/Analysis/AnalysisManager.cpp
+++ b/lib/Analysis/AnalysisManager.cpp
@@ -27,7 +27,7 @@
   // FIXME: Is getCodeDecl() always a named decl?
   if (isa<FunctionDecl>(getCodeDecl()) ||
       isa<ObjCMethodDecl>(getCodeDecl())) {
-    NamedDecl *ND = cast<NamedDecl>(getCodeDecl());
+    const NamedDecl *ND = cast<NamedDecl>(getCodeDecl());
     SourceManager &SM = getContext().getSourceManager();
     llvm::cerr << "ANALYZE: "
                << SM.getPresumedLoc(ND->getLocation()).getFilename()
diff --git a/lib/Analysis/CheckObjCDealloc.cpp b/lib/Analysis/CheckObjCDealloc.cpp
index 7e6023a..3392fcf 100644
--- a/lib/Analysis/CheckObjCDealloc.cpp
+++ b/lib/Analysis/CheckObjCDealloc.cpp
@@ -87,13 +87,13 @@
   return false;
 }
 
-void clang::CheckObjCDealloc(ObjCImplementationDecl* D,
+void clang::CheckObjCDealloc(const ObjCImplementationDecl* D,
                              const LangOptions& LOpts, BugReporter& BR) {
 
   assert (LOpts.getGCMode() != LangOptions::GCOnly);
   
   ASTContext& Ctx = BR.getContext();
-  ObjCInterfaceDecl* ID = D->getClassInterface();
+  const ObjCInterfaceDecl* ID = D->getClassInterface();
     
   // Does the class contain any ivars that are pointers (or id<...>)?
   // If not, skip the check entirely.
diff --git a/lib/Analysis/CheckObjCInstMethSignature.cpp b/lib/Analysis/CheckObjCInstMethSignature.cpp
index c208a7c..aae1e1d 100644
--- a/lib/Analysis/CheckObjCInstMethSignature.cpp
+++ b/lib/Analysis/CheckObjCInstMethSignature.cpp
@@ -36,10 +36,10 @@
   return C.typesAreCompatible(Derived, Ancestor);
 }
 
-static void CompareReturnTypes(ObjCMethodDecl* MethDerived,
-                               ObjCMethodDecl* MethAncestor,
-                               BugReporter& BR, ASTContext& Ctx,
-                               ObjCImplementationDecl* ID) {
+static void CompareReturnTypes(const ObjCMethodDecl *MethDerived,
+                               const ObjCMethodDecl *MethAncestor,
+                               BugReporter &BR, ASTContext &Ctx,
+                               const ObjCImplementationDecl *ID) {
     
   QualType ResDerived  = MethDerived->getResultType();
   QualType ResAncestor = MethAncestor->getResultType(); 
@@ -69,11 +69,11 @@
   }
 }
 
-void clang::CheckObjCInstMethSignature(ObjCImplementationDecl* ID,
+void clang::CheckObjCInstMethSignature(const ObjCImplementationDecl* ID,
                                        BugReporter& BR) {
   
-  ObjCInterfaceDecl* D = ID->getClassInterface();
-  ObjCInterfaceDecl* C = D->getSuperClass();
+  const ObjCInterfaceDecl* D = ID->getClassInterface();
+  const ObjCInterfaceDecl* C = D->getSuperClass();
 
   if (!C)
     return;
diff --git a/lib/Analysis/CheckObjCUnusedIVars.cpp b/lib/Analysis/CheckObjCUnusedIVars.cpp
index 3a69e00..7547097 100644
--- a/lib/Analysis/CheckObjCUnusedIVars.cpp
+++ b/lib/Analysis/CheckObjCUnusedIVars.cpp
@@ -62,7 +62,8 @@
     I->second = Used;
 }
 
-void clang::CheckObjCUnusedIvar(ObjCImplementationDecl* D, BugReporter& BR) {
+void clang::CheckObjCUnusedIvar(const ObjCImplementationDecl *D,
+                                BugReporter &BR) {
 
   const ObjCInterfaceDecl* ID = D->getClassInterface();
   IvarUsageMap M;
diff --git a/lib/Analysis/CheckSecuritySyntaxOnly.cpp b/lib/Analysis/CheckSecuritySyntaxOnly.cpp
index 17fc6d7..96c42f8 100644
--- a/lib/Analysis/CheckSecuritySyntaxOnly.cpp
+++ b/lib/Analysis/CheckSecuritySyntaxOnly.cpp
@@ -229,7 +229,7 @@
 // Entry point for check.
 //===----------------------------------------------------------------------===//
 
-void clang::CheckSecuritySyntaxOnly(Decl *D, BugReporter &BR) {  
+void clang::CheckSecuritySyntaxOnly(const Decl *D, BugReporter &BR) {  
   WalkAST walker(BR);
   walker.Visit(D->getBody());  
 }
diff --git a/lib/Analysis/GRExprEngine.cpp b/lib/Analysis/GRExprEngine.cpp
index a8d3407..f4711a1 100644
--- a/lib/Analysis/GRExprEngine.cpp
+++ b/lib/Analysis/GRExprEngine.cpp
@@ -148,8 +148,8 @@
 }
 
 
-GRExprEngine::GRExprEngine(CFG& cfg, Decl& CD, ASTContext& Ctx,
-                           LiveVariables& L, AnalysisManager &mgr,
+GRExprEngine::GRExprEngine(CFG &cfg, const Decl &CD, ASTContext &Ctx,
+                           LiveVariables &L, AnalysisManager &mgr,
                            bool purgeDead, bool eagerlyAssume,
                            StoreManagerCreator SMC,
                            ConstraintManagerCreator CMC)