diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -290,6 +290,8 @@
   (`#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
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/clang/include/clang/AST/RawCommentList.h b/clang/include/clang/AST/RawCommentList.h
--- a/clang/include/clang/AST/RawCommentList.h
+++ b/clang/include/clang/AST/RawCommentList.h
@@ -115,6 +115,17 @@
     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.
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -11377,6 +11377,8 @@
 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 {
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -2390,7 +2390,7 @@
       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 @@
     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");
diff --git a/clang/test/Lexer/comment-escape.c b/clang/test/Lexer/comment-escape.c
--- a/clang/test/Lexer/comment-escape.c
+++ b/clang/test/Lexer/comment-escape.c
@@ -1,6 +1,38 @@
-// RUN: %clang -fsyntax-only %s 
+// RUN: %clang -fsyntax-only -Wdocumentation %s
 // rdar://6757323
 // foo \
 
 #define blork 32
 
+// GH62054
+
+/**<*\
+/
+//expected-warning@-2 {{escaped newline between}} \
+//expected-warning@-2 {{line splicing in Doxygen comments are not supported}}
+
+/**<*\	
+/
+//expected-warning@-2 {{escaped newline between}} \
+//expected-warning@-2 {{backslash and newline separated by space}} \
+//expected-warning@-2 {{line splicing in Doxygen comments are not supported}}
+
+
+/*<*\
+/
+//expected-warning@-2 {{escaped newline between}}  \
+//expected-warning@-2 {{line splicing in Doxygen comments are not supported}}
+
+/*<*\	
+/
+//expected-warning@-2 {{escaped newline between}} \
+//expected-warning@-2 {{backslash and newline separated by space}} \
+//expected-warning@-2 {{line splicing in Doxygen comments are not supported}}
+
+/\
+*<**/
+//expected-warning@-2 {{line splicing in Doxygen comments are not supported}}
+
+/\
+/<*
+//expected-warning@-2 {{line splicing in Doxygen comments are not supported}}