From 51c994d8f0dd465fbcf9db758ba1399fb1a14545 Mon Sep 17 00:00:00 2001 From: Akim Demaille Date: Thu, 20 Sep 2012 17:17:02 +0200 Subject: [PATCH] TODO: lalr1.cc master vs maint * TODO: here. --- TODO | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/TODO b/TODO index 25fce499..051ca7c6 100644 --- a/TODO +++ b/TODO @@ -7,6 +7,29 @@ sure to check that the initial-action is performed once per parsing. b4_shared_declarations is no longer what it is. Make it b4_parser_declaration for instance. +** yychar in lalr1.cc +There is a large difference bw maint and master on the handling of +yychar (which was removed in lalr1.cc). See what needs to be +back-ported. + + + /* User semantic actions sometimes alter yychar, and that requires + that yytoken be updated with the new translation. We take the + approach of translating immediately before every use of yytoken. + One alternative is translating here after every semantic action, + but that translation would be missed if the semantic action + invokes YYABORT, YYACCEPT, or YYERROR immediately after altering + yychar. In the case of YYABORT or YYACCEPT, an incorrect + destructor might then be invoked immediately. In the case of + YYERROR, subsequent parser actions might lead to an incorrect + destructor call or verbose syntax error message before the + lookahead is translated. */ + + /* Make sure we have latest lookahead translation. See comments at + user semantic actions for why this is necessary. */ + yytoken = yytranslate_ (yychar); + + ** $ and others in epilogue A stray $ is a warning in the actions, but an error in the epilogue. IMHO, it should not even be a warning in the epilogue. -- 2.45.2