4 files changed, 25 insertions, 47 deletions

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 8e7410c47c7..7cb035b8680 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -1076,11 +1076,6 @@ QualType ASTContext::getTypeDeclType(TypeDecl *Decl, TypeDecl* PrevDecl) {
   return QualType(Decl->TypeForDecl, 0);
 }
 
-void ASTContext::setTagDefinition(TagDecl* D) {
-  assert (D->isDefinition());
-  cast<TagType>(D->TypeForDecl)->decl = D;  
-}
-
 /// getTypedefType - Return the unique reference to the type for the
 /// specified typename decl.
 QualType ASTContext::getTypedefType(TypedefDecl *Decl) {
diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index 0bc0043ccb8..8ae93110170 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -144,13 +144,8 @@ void EnumDecl::Destroy(ASTContext& C) {
 
 void EnumDecl::completeDefinition(ASTContext &C, QualType NewType) {
   assert(!isDefinition() && "Cannot redefine enums!");
-  setDefinition(true);
-
   IntegerType = NewType;
-
-  // Let ASTContext know that this is the defining EnumDecl for this
-  // type.
-  C.setTagDefinition(this);
+  TagDecl::completeDefinition();
 }
 
 FileScopeAsmDecl *FileScopeAsmDecl::Create(ASTContext &C,
@@ -311,6 +306,20 @@ OverloadedOperatorKind FunctionDecl::getOverloadedOperator() const {
 // TagDecl Implementation
 //===----------------------------------------------------------------------===//
 
+void TagDecl::startDefinition() {
+  cast<TagType>(TypeForDecl)->decl.setPointer(this);
+  cast<TagType>(TypeForDecl)->decl.setInt(1);
+}
+
+void TagDecl::completeDefinition() {
+  assert((!TypeForDecl || 
+          cast<TagType>(TypeForDecl)->decl.getPointer() == this) &&
+         "Attempt to redefine a tag definition?");
+  IsDefinition = true;
+  cast<TagType>(TypeForDecl)->decl.setPointer(this);
+  cast<TagType>(TypeForDecl)->decl.setInt(0);
+}
+
 TagDecl* TagDecl::getDefinition(ASTContext& C) const {
   QualType T = C.getTypeDeclType(const_cast<TagDecl*>(this));
   TagDecl* D = cast<TagDecl>(cast<TagType>(T)->getDecl());  
@@ -351,12 +360,7 @@ void RecordDecl::Destroy(ASTContext& C) {
 /// complete.
 void RecordDecl::completeDefinition(ASTContext& C) {
   assert(!isDefinition() && "Cannot redefine record!");
-
-  setDefinition(true);
-  
-  // Let ASTContext know that this is the defining RecordDecl for this
-  // type.
-  C.setTagDefinition(this);
+  TagDecl::completeDefinition();
 }
 
 //===----------------------------------------------------------------------===//
diff --git a/clang/lib/AST/DeclBase.cpp b/clang/lib/AST/DeclBase.cpp
index 860a65a1e3e..28656873ab0 100644
--- a/clang/lib/AST/DeclBase.cpp
+++ b/clang/lib/AST/DeclBase.cpp
@@ -442,37 +442,15 @@ DeclContext *DeclContext::getPrimaryContext() {
     return static_cast<NamespaceDecl*>(this)->getOriginalNamespace();
 
   case Decl::Enum:
-#if 0
-    // FIXME: See the comment for CXXRecord, below.
-    // The declaration associated with the enumeration type is our
-    // primary context.
-    return Context.getTypeDeclType(static_cast<EnumDecl*>(this))
-             ->getAsEnumType()->getDecl();
-#else
-    return this;
-#endif
-
   case Decl::Record:
-  case Decl::CXXRecord: {
-    // The declaration associated with the type is be our primary
-    // context. 
-#if 0
-    // FIXME: This is what we expect to do. However, it doesn't work
-    // because ASTContext::setTagDefinition changes the result of
-    // Context.getTypeDeclType, meaning that our "primary" declaration
-    // of a RecordDecl/CXXRecordDecl will change, and we won't be able
-    // to find any values inserted into the earlier "primary"
-    // declaration. We need better tracking of redeclarations and
-    // definitions.
-    QualType Type = Context.getTypeDeclType(static_cast<RecordDecl*>(this));
-    return Type->getAsRecordType()->getDecl();
-#else
-    // FIXME: This hack will work for now, because the declaration we
-    // create when we're defining the record is the one we'll use as
-    // the definition later.
+  case Decl::CXXRecord:
+    // If this is a tag type that has a definition or is currently
+    // being defined, that definition is our primary context.
+    if (TagType *TagT = cast_or_null<TagType>(cast<TagDecl>(this)->TypeForDecl))
+      if (TagT->isBeingDefined() || 
+          (TagT->getDecl() && TagT->getDecl()->isDefinition()))
+        return TagT->getDecl();
     return this;
-#endif
-  }
 
   case Decl::ObjCMethod:
     return this;
diff --git a/clang/lib/AST/TypeSerialization.cpp b/clang/lib/AST/TypeSerialization.cpp
index 42569da400a..4f3eeca28c6 100644
--- a/clang/lib/AST/TypeSerialization.cpp
+++ b/clang/lib/AST/TypeSerialization.cpp
@@ -258,7 +258,8 @@ Type* TagType::CreateImpl(ASTContext& Context, Deserializer& D) {
   Types.push_back(T);
   
   // Deserialize the decl.
-  T->decl = cast<TagDecl>(D.ReadOwnedPtr<Decl>(Context));
+  T->decl.setPointer(cast<TagDecl>(D.ReadOwnedPtr<Decl>(Context)));
+  T->decl.setInt(0);
 
   return T;
 }