From: Douglas Gregor <dgregor@apple.com>
Date: Mon, 9 Nov 2009 22:08:55 +0000 (+0000)
Subject: Make sure that Type::getAs<ArrayType>() (or Type::getAs<subclass of
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=89c49f09b0292dc7c03885f6c765d667a9837597;p=clang

Make sure that Type::getAs<ArrayType>() (or Type::getAs<subclass of
ArrayType>()) does not instantiate. Update all callers that used this
unsafe feature to use the appropriate ASTContext::getAs*ArrayType method.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@86596 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/AST/Type.h b/include/clang/AST/Type.h
index e53b9787af..8727650031 100644
--- a/include/clang/AST/Type.h
+++ b/include/clang/AST/Type.h
@@ -2927,8 +2927,21 @@ inline const DiagnosticBuilder &operator<<(const DiagnosticBuilder &DB,
   return DB;
 }
 
+// Helper class template that is used by Type::getAs to ensure that one does
+// not try to look through a qualified type to get to an array type.
+template<typename T,
+         bool isArrayType = (llvm::is_same<T, ArrayType>::value ||
+                             llvm::is_base_of<ArrayType, T>::value)>
+struct ArrayType_cannot_be_used_with_getAs { };
+  
+template<typename T>
+struct ArrayType_cannot_be_used_with_getAs<T, true>;
+  
 /// Member-template getAs<specific type>'.
 template <typename T> const T *Type::getAs() const {
+  ArrayType_cannot_be_used_with_getAs<T> at;
+  (void)at;
+  
   // If this is directly a T type, return it.
   if (const T *Ty = dyn_cast<T>(this))
     return Ty;
diff --git a/lib/Analysis/RegionStore.cpp b/lib/Analysis/RegionStore.cpp
index dbf8c42d27..45c42281ab 100644
--- a/lib/Analysis/RegionStore.cpp
+++ b/lib/Analysis/RegionStore.cpp
@@ -1109,7 +1109,7 @@ SVal RegionStoreManager::RetrieveElement(const GRState* state,
     // FIXME: Handle loads from strings where the literal is treated as 
     // an integer, e.g., *((unsigned int*)"hello")
     ASTContext &Ctx = getContext();
-    QualType T = StrR->getValueType(Ctx)->getAs<ArrayType>()->getElementType();
+    QualType T = Ctx.getAsArrayType(StrR->getValueType(Ctx))->getElementType();
     if (T != Ctx.getCanonicalType(R->getElementType()))
       return UnknownVal();
     
diff --git a/lib/Analysis/VLASizeChecker.cpp b/lib/Analysis/VLASizeChecker.cpp
index 98b755be53..5cb700ed67 100644
--- a/lib/Analysis/VLASizeChecker.cpp
+++ b/lib/Analysis/VLASizeChecker.cpp
@@ -43,7 +43,8 @@ void VLASizeChecker::PreVisitDeclStmt(CheckerContext &C, const DeclStmt *DS) {
   if (!VD)
     return;
   
-  const VariableArrayType *VLA = VD->getType()->getAs<VariableArrayType>();
+  const VariableArrayType *VLA
+    = C.getASTContext().getAsVariableArrayType(VD->getType());
   if (!VLA)
     return;
 
diff --git a/lib/CodeGen/CGDecl.cpp b/lib/CodeGen/CGDecl.cpp
index 2021ced316..2a28ef08a0 100644
--- a/lib/CodeGen/CGDecl.cpp
+++ b/lib/CodeGen/CGDecl.cpp
@@ -507,7 +507,7 @@ void CodeGenFunction::EmitLocalBlockVarDecl(const VarDecl &D) {
 
   // Handle CXX destruction of variables.
   QualType DtorTy(Ty);
-  if (const ArrayType *Array = DtorTy->getAs<ArrayType>())
+  while (const ArrayType *Array = getContext().getAsArrayType(DtorTy))
     DtorTy = getContext().getBaseElementType(Array);
   if (const RecordType *RT = DtorTy->getAs<RecordType>())
     if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index cfea66bf5a..8bd934a561 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -3596,7 +3596,7 @@ Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS,
         // template <typename... Args> void f(Args... args) {
         //   int vals[] = { args };
         // }
-        const IncompleteArrayType *IAT = T->getAs<IncompleteArrayType>();
+        const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T);
         Expr *Init = IDecl->getInit();
         if (IAT && Init &&
             (Init->isTypeDependent() || Init->isValueDependent())) {
diff --git a/lib/Sema/SemaOverload.cpp b/lib/Sema/SemaOverload.cpp
index 69dac7d33e..69e5a52307 100644
--- a/lib/Sema/SemaOverload.cpp
+++ b/lib/Sema/SemaOverload.cpp
@@ -2982,7 +2982,7 @@ BuiltinCandidateTypeSet::AddPointerWithMoreQualifiedTypeVariants(QualType Ty,
 
   QualType PointeeTy = PointerTy->getPointeeType();
   unsigned BaseCVR = PointeeTy.getCVRQualifiers();
-  if (const ConstantArrayType *Array = PointeeTy->getAs<ConstantArrayType>())
+  if (const ConstantArrayType *Array =Context.getAsConstantArrayType(PointeeTy))
     BaseCVR = Array->getElementType().getCVRQualifiers();
   bool hasVolatile = VisibleQuals.hasVolatile();
   bool hasRestrict = VisibleQuals.hasRestrict();
diff --git a/lib/Sema/SemaType.cpp b/lib/Sema/SemaType.cpp
index 93ef1ea2ea..00dc809f51 100644
--- a/lib/Sema/SemaType.cpp
+++ b/lib/Sema/SemaType.cpp
@@ -1704,7 +1704,7 @@ bool Sema::RequireCompleteType(SourceLocation Loc, QualType T,
   // class template specialization, or an array with known size of such,
   // try to instantiate it.
   QualType MaybeTemplate = T;
-  if (const ConstantArrayType *Array = T->getAs<ConstantArrayType>())
+  if (const ConstantArrayType *Array = Context.getAsConstantArrayType(T))
     MaybeTemplate = Array->getElementType();
   if (const RecordType *Record = MaybeTemplate->getAs<RecordType>()) {
     if (ClassTemplateSpecializationDecl *ClassTemplateSpec