[PATCH] Represent empty declaration using a new Decl node EmptyDecl and let attribute declarations appertain to EmptyDecl.

[Richard Smith]

================
Comment at: include/clang/Sema/Sema.h:1451-1453
@@ -1450,3 +1450,5 @@
   /// \brief Handle a C++11 attribute-declaration.
-  void ActOnAttributeDeclaration(AttributeList *AttrList);
+  Decl *ActOnAttributeDeclaration(AttributeList *AttrList,
+                                  SourceLocation AttrListEndLoc,
+                                  Scope *S);
 
----------------
Rename this to ActOnEmptyDeclaration. Rename AttrListEndLoc to SemiLoc or similar. The 'Scope *' parameter is usually the first parameter.

================
Comment at: lib/AST/DeclPrinter.cpp:724
@@ +723,3 @@
+void DeclPrinter::VisitEmptyDecl(EmptyDecl *D) {
+  Out << ";\n";
+}
----------------
Call prettyPrintAttributes(D); before this.

================
Comment at: lib/Parse/Parser.cpp:629-636
@@ -628,8 +628,9 @@
     // Either a C++11 empty-declaration or attribute-declaration.
     if (attrs.Range.isValid()) {
-      // FIXME: Add an AST representation for this.
-      Actions.ActOnAttributeDeclaration(attrs.getList());
-      return DeclGroupPtrTy();
+      Decl *D = Actions.ActOnAttributeDeclaration(attrs.getList(),
+                                                  attrs.Range.getEnd(),
+                                                  getCurScope());
+      return Actions.ConvertDeclToDeclGroup(D);
     }
 
     ConsumeExtraSemi(OutsideFunction);
----------------
Call ActOnEmptyDeclaration here whether or not we have attributes. Just set SingleDecl and break; the later code will do the ConvertDeclToDeclGroup for you.

================
Comment at: lib/Sema/SemaDeclCXX.cpp:10102
@@ -10101,3 @@
-           ? diag::warn_unknown_attribute_ignored
-           : diag::err_attribute_declaration)
-      << AttrList->getName();
----------------
Please remove this from DiagnosticSemaKinds.td too.


http://llvm-reviews.chandlerc.com/D448