Replace TypeLoc llvm::cast support to be well-defined.

The TypeLoc hierarchy used the llvm::cast machinery to perform undefined
behavior by casting pointers/references to TypeLoc objects to derived types
and then using the derived copy constructors (or even returning pointers to
derived types that actually point to the original TypeLoc object).

Some context is in this thread:
http://lists.cs.uiuc.edu/pipermail/llvmdev/2012-December/056804.html
Though it's spread over a few months which can be hard to read in the mail
archive.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175462 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 23 insertions, 23 deletions

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index d425902699..7667681c79 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -4066,29 +4066,29 @@ static QualType TryToFixInvalidVariablyModifiedType(QualType T,
 
 static void
 FixInvalidVariablyModifiedTypeLoc(TypeLoc SrcTL, TypeLoc DstTL) {
-  if (PointerTypeLoc* SrcPTL = dyn_cast<PointerTypeLoc>(&SrcTL)) {
-    PointerTypeLoc* DstPTL = cast<PointerTypeLoc>(&DstTL);
-    FixInvalidVariablyModifiedTypeLoc(SrcPTL->getPointeeLoc(),
-                                      DstPTL->getPointeeLoc());
-    DstPTL->setStarLoc(SrcPTL->getStarLoc());
+  if (PointerTypeLoc SrcPTL = SrcTL.getAs<PointerTypeLoc>()) {
+    PointerTypeLoc DstPTL = DstTL.castAs<PointerTypeLoc>();
+    FixInvalidVariablyModifiedTypeLoc(SrcPTL.getPointeeLoc(),
+                                      DstPTL.getPointeeLoc());
+    DstPTL.setStarLoc(SrcPTL.getStarLoc());
     return;
   }
-  if (ParenTypeLoc* SrcPTL = dyn_cast<ParenTypeLoc>(&SrcTL)) {
-    ParenTypeLoc* DstPTL = cast<ParenTypeLoc>(&DstTL);
-    FixInvalidVariablyModifiedTypeLoc(SrcPTL->getInnerLoc(),
-                                      DstPTL->getInnerLoc());
-    DstPTL->setLParenLoc(SrcPTL->getLParenLoc());
-    DstPTL->setRParenLoc(SrcPTL->getRParenLoc());
+  if (ParenTypeLoc SrcPTL = SrcTL.getAs<ParenTypeLoc>()) {
+    ParenTypeLoc DstPTL = DstTL.castAs<ParenTypeLoc>();
+    FixInvalidVariablyModifiedTypeLoc(SrcPTL.getInnerLoc(),
+                                      DstPTL.getInnerLoc());
+    DstPTL.setLParenLoc(SrcPTL.getLParenLoc());
+    DstPTL.setRParenLoc(SrcPTL.getRParenLoc());
     return;
   }
-  ArrayTypeLoc* SrcATL = cast<ArrayTypeLoc>(&SrcTL);
-  ArrayTypeLoc* DstATL = cast<ArrayTypeLoc>(&DstTL);
-  TypeLoc SrcElemTL = SrcATL->getElementLoc();
-  TypeLoc DstElemTL = DstATL->getElementLoc();
+  ArrayTypeLoc SrcATL = SrcTL.castAs<ArrayTypeLoc>();
+  ArrayTypeLoc DstATL = DstTL.castAs<ArrayTypeLoc>();
+  TypeLoc SrcElemTL = SrcATL.getElementLoc();
+  TypeLoc DstElemTL = DstATL.getElementLoc();
   DstElemTL.initializeFullCopy(SrcElemTL);
-  DstATL->setLBracketLoc(SrcATL->getLBracketLoc());
-  DstATL->setSizeExpr(SrcATL->getSizeExpr());
-  DstATL->setRBracketLoc(SrcATL->getRBracketLoc());
+  DstATL.setLBracketLoc(SrcATL.getLBracketLoc());
+  DstATL.setSizeExpr(SrcATL.getSizeExpr());
+  DstATL.setRBracketLoc(SrcATL.getRBracketLoc());
 }
 
 /// Helper method to turn variable array types into constant array
@@ -6600,12 +6600,12 @@ static SourceRange getResultSourceRange(const FunctionDecl *FD) {
     return SourceRange();
 
   TypeLoc TL = TSI->getTypeLoc();
-  FunctionTypeLoc *FunctionTL = dyn_cast<FunctionTypeLoc>(&TL);
+  FunctionTypeLoc FunctionTL = TL.getAs<FunctionTypeLoc>();
   if (!FunctionTL)
     return SourceRange();
 
-  TypeLoc ResultTL = FunctionTL->getResultLoc();
-  if (isa<BuiltinTypeLoc>(ResultTL.getUnqualifiedLoc()))
+  TypeLoc ResultTL = FunctionTL.getResultLoc();
+  if (ResultTL.getUnqualifiedLoc().getAs<BuiltinTypeLoc>())
     return ResultTL.getSourceRange();
 
   return SourceRange();
@@ -8291,11 +8291,11 @@ Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D) {
       // but that could be a zero-parameter prototype
       TypeSourceInfo* TI = PossibleZeroParamPrototype->getTypeSourceInfo();
       TypeLoc TL = TI->getTypeLoc();
-      if (FunctionNoProtoTypeLoc* FTL = dyn_cast<FunctionNoProtoTypeLoc>(&TL))
+      if (FunctionNoProtoTypeLoc FTL = TL.getAs<FunctionNoProtoTypeLoc>())
         Diag(PossibleZeroParamPrototype->getLocation(), 
              diag::note_declaration_not_a_prototype)
           << PossibleZeroParamPrototype 
-          << FixItHint::CreateInsertion(FTL->getRParenLoc(), "void");
+          << FixItHint::CreateInsertion(FTL.getRParenLoc(), "void");
     }
   }