Enable comment parsing and semantic analysis to emit diagnostics. A few

diagnostics implemented -- see testcases.

I created a new TableGen file for comment diagnostics,
DiagnosticCommentKinds.td, because comment diagnostics don't logically
fit into AST diagnostics file.  But I don't feel strongly about it.

This also implements support for self-closing HTML tags in comment
lexer and parser (for example, <br />).

In order to issue precise diagnostics CommentSema needs to know the
declaration the comment is attached to.  There is no easy way to find a decl by 
comment, so we match comments and decls in lockstep: after parsing one
declgroup we check if we have any new, not yet attached comments.  If we do --
then we do the usual comment-finding process.

It is interesting that this automatically handles trailing comments.
We pick up not only comments that precede the declaration, but also
comments that *follow* the declaration -- thanks to the lookahead in
the lexer: after parsing the declgroup we've consumed the semicolon
and looked ahead through comments.

Added -Wdocumentation-html flag for semantic HTML errors to allow the user to 
disable only HTML warnings (but not HTML parse errors, which we emit as
warnings in -Wdocumentation).

llvm-svn: 160078

1 files changed, 1 insertions, 1 deletions

diff --git a/clang/lib/AST/RawCommentList.cpp b/clang/lib/AST/RawCommentList.cpp
index d67eb0822f2..7e183e2f2d3 100644
--- a/clang/lib/AST/RawCommentList.cpp
+++ b/clang/lib/AST/RawCommentList.cpp
@@ -61,7 +61,7 @@ bool mergedCommentIsTrailingComment(StringRef Comment) {
 RawComment::RawComment(const SourceManager &SourceMgr, SourceRange SR,
                        bool Merged) :
     Range(SR), RawTextValid(false), BriefTextValid(false),
-    IsAlmostTrailingComment(false),
+    IsAttached(false), IsAlmostTrailingComment(false),
     BeginLineValid(false), EndLineValid(false) {
   // Extract raw comment text, if possible.
   if (SR.getBegin() == SR.getEnd() || getRawText(SourceMgr).empty()) {