Merge commit 'b20c1ffe8f3e' from llvm.org/main into experimental/cas/main

Author: git apple-llvm automerger

clang/docs/ReleaseNotes.rst

@@ -290,6 +290,8 @@ Bug Fixes in This Version
   (`#61142 <https://github.com/llvm/llvm-project/issues/61142>`_)
 - Clang now better diagnose placeholder types constrained with a concept that is
   not a type concept.
+- Fix crash when a doc comment contains a line splicing.
+  (`#62054 <https://github.com/llvm/llvm-project/issues/62054>`_)
 
 Bug Fixes to Compiler Builtins
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

clang/include/clang/AST/RawCommentList.h

@@ -115,6 +115,17 @@ class RawComment {
     return extractBriefText(Context);
   }
 
+  bool hasUnsupportedSplice(const SourceManager &SourceMgr) const {
+    if (!isInvalid())
+      return false;
+    StringRef Text = getRawText(SourceMgr);
+    if (Text.size() < 6 || Text[0] != '/')
+      return false;
+    if (Text[1] == '*')
+      return Text[Text.size() - 1] != '/' || Text[Text.size() - 2] != '*';
+    return Text[1] != '/';
+  }
+
   /// Returns sanitized comment text, suitable for presentation in editor UIs.
   /// E.g. will transform:
   ///     // This is a long multiline comment.

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -11377,6 +11377,8 @@ def err_coro_invalid_addr_of_label : Error<
 let CategoryName = "Documentation Issue" in {
 def warn_not_a_doxygen_trailing_member_comment : Warning<
   "not a Doxygen trailing comment">, InGroup<Documentation>, DefaultIgnore;
+def warn_splice_in_doxygen_comment : Warning<
+  "line splicing in Doxygen comments are not supported">, InGroup<Documentation>, DefaultIgnore;
 } // end of documentation issue category
 
 let CategoryName = "Nullability Issue" in {

clang/lib/Sema/Sema.cpp

@@ -2390,7 +2390,7 @@ void Sema::ActOnComment(SourceRange Comment) {
       SourceMgr.isInSystemHeader(Comment.getBegin()))
     return;
   RawComment RC(SourceMgr, Comment, LangOpts.CommentOpts, false);
-  if (RC.isAlmostTrailingComment()) {
+  if (RC.isAlmostTrailingComment() || RC.hasUnsupportedSplice(SourceMgr)) {
     SourceRange MagicMarkerRange(Comment.getBegin(),
                                  Comment.getBegin().getLocWithOffset(3));
     StringRef MagicMarkerText;
@@ -2401,6 +2401,11 @@ void Sema::ActOnComment(SourceRange Comment) {
     case RawComment::RCK_OrdinaryC:
       MagicMarkerText = "/**<";
       break;
+    case RawComment::RCK_Invalid:
+      // FIXME: are there other scenarios that could produce an invalid
+      // raw comment here?
+      Diag(Comment.getBegin(), diag::warn_splice_in_doxygen_comment);
+      return;
     default:
       llvm_unreachable("if this is an almost Doxygen comment, "
                        "it should be ordinary");