Step #1/N of implementing support for __label__: split labels into

LabelDecl and LabelStmt.  There is a 1-1 correspondence between the
two, but this simplifies a bunch of code by itself.  This is because
labels are the only place where we previously had references to random
other statements, causing grief for AST serialization and other stuff.

This does cause one regression (attr(unused) doesn't silence unused
label warnings) which I'll address next.

This does fix some minor bugs:
1. "The only valid attribute " diagnostic was capitalized.
2. Various diagnostics printed as ''labelname'' instead of 'labelname'
3. This reduces duplication of label checking between functions and blocks.

Review appreciated, particularly for the cindex and template bits.

llvm-svn: 125733

1 files changed, 8 insertions, 0 deletions

diff --git a/clang/lib/Serialization/ASTWriterDecl.cpp b/clang/lib/Serialization/ASTWriterDecl.cpp
index 17ee85ad279..dd43e1a05db 100644
--- a/clang/lib/Serialization/ASTWriterDecl.cpp
+++ b/clang/lib/Serialization/ASTWriterDecl.cpp
@@ -47,6 +47,7 @@ namespace clang {
     void VisitDecl(Decl *D);
     void VisitTranslationUnitDecl(TranslationUnitDecl *D);
     void VisitNamedDecl(NamedDecl *D);
+    void VisitLabelDecl(LabelDecl *LD);
     void VisitNamespaceDecl(NamespaceDecl *D);
     void VisitUsingDirectiveDecl(UsingDirectiveDecl *D);
     void VisitNamespaceAliasDecl(NamespaceAliasDecl *D);
@@ -651,6 +652,13 @@ void ASTDeclWriter::VisitLinkageSpecDecl(LinkageSpecDecl *D) {
   Code = serialization::DECL_LINKAGE_SPEC;
 }
 
+void ASTDeclWriter::VisitLabelDecl(LabelDecl *D) {
+  VisitNamedDecl(D);
+  Record.push_back(D->hasUnusedAttribute());
+  Code = serialization::DECL_LABEL;
+}
+
+
 void ASTDeclWriter::VisitNamespaceDecl(NamespaceDecl *D) {
   VisitNamedDecl(D);
   Record.push_back(D->isInline());