Extract a common structure for holding information about the definition

of a C++ record.  Exposed a lot of problems where various routines were
silently doing The Wrong Thing (or The Acceptable Thing in The Wrong Order)
when presented with a non-definition.  Also cuts down on memory usage.

llvm-svn: 95330

1 files changed, 10 insertions, 0 deletions

diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index c3e976a080a..ba1def643e1 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -1373,6 +1373,16 @@ void TagDecl::startDefinition() {
     TagT->decl.setPointer(this);
     TagT->decl.setInt(1);
   }
+
+  if (isa<CXXRecordDecl>(this)) {
+    CXXRecordDecl *D = cast<CXXRecordDecl>(this);
+    struct CXXRecordDecl::DefinitionData *Data = 
+      new (getASTContext()) struct CXXRecordDecl::DefinitionData(D);
+    do {
+      D->DefinitionData = Data;
+      D = cast_or_null<CXXRecordDecl>(D->getPreviousDeclaration());
+    } while (D);
+  }
 }
 
 void TagDecl::completeDefinition() {