[Sema] Semantic analysis for empty-declaration and attribute-declaration.

Introduce a new AST Decl node "EmptyDecl" to model empty-declaration. Have attributes from attribute-declaration appertain
to the EmptyDecl node by creating the AST representations of these attributes and attach them to the EmptyDecl node so these
attributes can be sema checked just as attributes attached to "normal" declarations.

llvm-svn: 175900

1 files changed, 11 insertions, 17 deletions

diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 8198856547c..ce526a9ed39 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -10085,23 +10085,17 @@ Decl *Sema::ActOnFinishLinkageSpecification(Scope *S,
   return LinkageSpec;
 }
 
-/// \brief Perform semantic checks on a C++11 attribute-declaration.
-void Sema::ActOnAttributeDeclaration(AttributeList *AttrList) {
-  // FIXME: Build an AST node for an attribute declaration and return it.
-  
-  // Since we do not support any attributes which can be used in an attribute
-  // declaration, just diagnose standard and unknown attributes appropriately.
-  for (/**/; AttrList; AttrList = AttrList->getNext()) {
-    if (AttrList->getKind() == AttributeList::IgnoredAttribute ||
-        AttrList->isInvalid())
-      continue;
-
-    Diag(AttrList->getLoc(),
-         AttrList->getKind() == AttributeList::UnknownAttribute
-           ? diag::warn_unknown_attribute_ignored
-           : diag::err_attribute_declaration)
-      << AttrList->getName();
-  }
+Decl *Sema::ActOnEmptyDeclaration(Scope *S,
+                                  AttributeList *AttrList,
+                                  SourceLocation SemiLoc) {
+  Decl *ED = EmptyDecl::Create(Context, CurContext, SemiLoc);
+  // Attribute declarations appertain to empty declaration so we handle
+  // them here.
+  if (AttrList)
+    ProcessDeclAttributeList(S, ED, AttrList);
+
+  CurContext->addDecl(ED);
+  return ED;
 }
 
 /// \brief Perform semantic analysis for the variable declaration that