Comment parsing: handle \deprecated command. It is a block command, but it

should be fine to use it without further explanations in the attached
paragraph, so the warning about empty paragraph was turned off for it.

llvm-svn: 163836

clang/include/clang/AST/CommentCommandTraits.h

@@ -66,6 +66,10 @@ struct CommandInfo {
   /// a template parameter (\\tparam or an alias).
   unsigned IsTParamCommand : 1;
 
+  /// True if we don't want to warn about this command being passed an empty
+  /// paragraph.  Meaningful only for block commands.
+  unsigned IsEmptyParagraphAllowed : 1;
+
   /// \brief True if this command is a verbatim-like block command.
   ///
   /// A verbatim-like block command eats every character (except line starting

clang/include/clang/AST/CommentCommands.td

@@ -12,6 +12,8 @@ class Command<string name> {
   bit IsParamCommand = 0;
   bit IsTParamCommand = 0;
 
+  bit IsEmptyParagraphAllowed = 0;
+
   bit IsVerbatimBlockCommand = 0;
   bit IsVerbatimBlockEndCommand = 0;
   bit IsVerbatimLineCommand = 0;
@@ -73,6 +75,8 @@ def Tparam : BlockCommand<"tparam"> { let IsTParamCommand = 1; }
 // HeaderDoc
 def Templatefield : BlockCommand<"templatefield"> { let IsTParamCommand = 1; }
 
+def Deprecated : BlockCommand<"deprecated"> { let IsEmptyParagraphAllowed = 1; }
+
 def Author     : BlockCommand<"author">;
 def Authors    : BlockCommand<"authors">;
 def Bug        : BlockCommand<"bug">;

clang/lib/AST/CommentSema.cpp

@@ -415,6 +415,9 @@ FullComment *Sema::actOnFullComment(
 }
 
 void Sema::checkBlockCommandEmptyParagraph(BlockCommandComment *Command) {
+  if (Traits.getCommandInfo(Command->getCommandID())->IsEmptyParagraphAllowed)
+    return;
+
   ParagraphComment *Paragraph = Command->getParagraph();
   if (Paragraph->isWhitespace()) {
     SourceLocation DiagLoc;

clang/test/Sema/warn-documentation.cpp

@@ -371,6 +371,19 @@ using test_tparam14 = test_tparam13<T, int>;
 template<typename T>
 using test_tparam15 = test_tparam13<T, int>;
 
+
+/// Aaa
+/// \deprecated Bbb
+void test_deprecated_1(int a);
+
+// We don't want \deprecated to warn about empty paragraph.  It is fine to use
+// \deprecated by itself without explanations.
+
+/// Aaa
+/// \deprecated
+void test_deprecated_2(int a);
+
+
 // no-warning
 /// \returns Aaa
 int test_returns_right_decl_1(int);

clang/utils/TableGen/ClangCommentCommandInfoEmitter.cpp

@@ -38,6 +38,7 @@ void EmitClangCommentCommandInfo(RecordKeeper &Records, raw_ostream &OS) {
        << Tag.getValueAsBit("IsReturnsCommand") << ", "
        << Tag.getValueAsBit("IsParamCommand") << ", "
        << Tag.getValueAsBit("IsTParamCommand") << ", "
+       << Tag.getValueAsBit("IsEmptyParagraphAllowed") << ", "
        << Tag.getValueAsBit("IsVerbatimBlockCommand") << ", "
        << Tag.getValueAsBit("IsVerbatimBlockEndCommand") << ", "
        << Tag.getValueAsBit("IsVerbatimLineCommand") << ", "