maint: run "make update-copyright"

[bison.git] / data / yacc.c

diff --git a/data/yacc.c b/data/yacc.c
index 25a7612bf206ee1acd2c97e44a2ac513fac5f119..4274673d95fbc0f569a92aae96fc048360557356 100644 (file)
--- a/data/yacc.c
+++ b/data/yacc.c
@@ -2,8 +2,8 @@
 
 # Yacc compatible skeleton for Bison
 
-# Copyright (C) 1984, 1989, 1990, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
-# 2007, 2008, 2009 Free Software Foundation, Inc.
+# Copyright (C) 1984, 1989-1990, 2000-2010 Free Software Foundation,
+# Inc.
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -217,8 +217,7 @@ m4_changecom()
 m4_divert_push(0)dnl
 @output(b4_parser_file_name@)@
 b4_copyright([Skeleton implementation for Bison's Yacc-like parsers in C],
-             [1984, 1989, 1990, 2000, 2001, 2002, 2003, 2004, 2005,
-              2006, 2007, 2008, 2009])[
+             [1984, 1989-1990, 2000-2010])[
 
 /* C LALR(1) parser skeleton written by Richard Stallman, by
    simplifying the original so-called "semantic" parser.  */
@@ -677,9 +676,18 @@ static const ]b4_int_type_for([b4_stos])[ yystos[] =
 
 /* Like YYERROR except do call yyerror.  This remains here temporarily
    to ease the transition to the new meaning of YYERROR, for GCC.
-   Once GCC version 2 has supplanted version 1, this can go.  */
+   Once GCC version 2 has supplanted version 1, this can go.  However,
+   YYFAIL appears to be in use.  Nevertheless, it is formally deprecated
+   in Bison 2.4.2's NEWS entry, where a plan to phase it out is
+   discussed.  */
 
 #define YYFAIL         goto yyerrlab
+#if defined YYFAIL
+  /* This is here to suppress warnings from the GCC cpp's
+     -Wunused-macros.  Normally we don't worry about that warning, but
+     some users do, and we want to make it easy for users to remove
+     YYFAIL uses, which will produce warnings from Bison 2.5.  */
+#endif
 
 #define YYRECOVERING()  (!!yyerrstatus)
 
@@ -689,7 +697,6 @@ do                                                          \
     {                                                          \
       yychar = (Token);                                                \
       yylval = (Value);                                                \
-      yytoken = YYTRANSLATE (yychar);                          \
       YYPOPSTACK (1);                                          \
       goto yybackup;                                           \
     }                                                          \
@@ -1486,6 +1493,17 @@ yyreduce:
       ]b4_user_actions[
       default: break;
     }
+  /* 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 or
+     if it invokes YYBACKUP.  In the case of YYABORT or YYACCEPT, an
+     incorrect destructor might then be invoked immediately.  In the
+     case of YYERROR or YYBACKUP, subsequent parser actions might lead
+     to an incorrect destructor call or verbose syntax error message
+     before the lookahead is translated.  */
   YY_SYMBOL_PRINT ("-> $$ =", yyr1[yyn], &yyval, &yyloc);
 
   YYPOPSTACK (yylen);
@@ -1514,6 +1532,10 @@ yyreduce:
 | yyerrlab -- here on detecting error |
 `------------------------------------*/
 yyerrlab:
+  /* Make sure we have latest lookahead translation.  See comments at
+     user semantic actions for why this is necessary.  */
+  yytoken = YYTRANSLATE (yychar);
+
   /* If not already recovering from an error, report this error.  */
   if (!yyerrstatus)
     {
@@ -1666,8 +1688,13 @@ yyexhaustedlab:
 
 yyreturn:
   if (yychar != YYEMPTY)
-     yydestruct ("Cleanup: discarding lookahead",
-                yytoken, &yylval]b4_locations_if([, &yylloc])[]b4_user_args[);
+    {
+      /* Make sure we have latest lookahead translation.  See comments at
+         user semantic actions for why this is necessary.  */
+      yytoken = YYTRANSLATE (yychar);
+      yydestruct ("Cleanup: discarding lookahead",
+                  yytoken, &yylval]b4_locations_if([, &yylloc])[]b4_user_args[);
+    }
   /* Do not reclaim the symbols of the rule which action triggered
      this YYABORT or YYACCEPT.  */
   YYPOPSTACK (yylen);
@@ -1698,8 +1725,7 @@ yypushreturn:]])[
 b4_defines_if(
 [@output(b4_spec_defines_file@)@
 b4_copyright([Skeleton interface for Bison's Yacc-like parsers in C],
-             [1984, 1989, 1990, 2000, 2001, 2002, 2003, 2004, 2005,
-              2006, 2007, 2008, 2009])
+             [1984, 1989-1990, 2000-2010])
 
 b4_percent_code_get([[requires]])[]dnl