diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -930,7 +930,8 @@
 def fcomment_block_commands : CommaJoined<["-"], "fcomment-block-commands=">, Group<f_clang_Group>, Flags<[CC1Option]>,
   HelpText<"Treat each comma separated argument in <arg> as a documentation comment block command">,
   MetaVarName<"<arg>">;
-def fparse_all_comments : Flag<["-"], "fparse-all-comments">, Group<f_clang_Group>, Flags<[CC1Option]>;
+def fparse_all_comments : Flag<["-"], "fparse-all-comments">, Group<f_clang_Group>, Flags<[CC1Option]>,
+  MarshallingInfoFlag<"LangOpts->CommentOpts.ParseAllComments">;
 def frecord_command_line : Flag<["-"], "frecord-command-line">,
   Group<f_clang_Group>;
 def fno_record_command_line : Flag<["-"], "fno-record-command-line">,