yysyntax_error: improve invocation readability.

[bison.git] / data / yacc.c

diff --git a/data/yacc.c b/data/yacc.c
index 5e7b55fc31e4af09232d323ca1e658db24c3d5ef..a32971767640f77c6e754b3ad2dabce7a3a74be0 100644 (file)
--- a/data/yacc.c
+++ b/data/yacc.c
@@ -1,12 +1,11 @@
                                                              -*- C -*-
 # Yacc compatible skeleton for Bison
 
                                                              -*- C -*-
 # 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, 2001, 2002, 2003, 2004, 2005,
+# 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.

 
 m4_pushdef([b4_copyright_years],
 
 m4_pushdef([b4_copyright_years],

-           [1984, 1989, 1990, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
-            2007, 2008, 2009])
+           [1984, 1989, 1990, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010])

 
 # 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
 
 # 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


@@ -206,7 +205,7 @@ m4_define([b4_declare_parser_state_variables], [b4_pure_if([[
     YYLTYPE *yylsp;
 
     /* The locations where the error started and ended.  */
     YYLTYPE *yylsp;
 
     /* The locations where the error started and ended.  */

-    YYLTYPE yyerror_range[2];]])[
+    YYLTYPE yyerror_range[3];]])[

 
     YYSIZE_T yystacksize;]])
 
 
     YYSIZE_T yystacksize;]])
 


@@ -420,10 +419,10 @@ typedef short int yytype_int16;
 #    define alloca _alloca
 #   else
 #    define YYSTACK_ALLOC alloca
 #    define alloca _alloca
 #   else
 #    define YYSTACK_ALLOC alloca

-#    if ! defined _ALLOCA_H && ! defined _STDLIB_H && ]b4_c_modern[
+#    if ! defined _ALLOCA_H && ! defined EXIT_SUCCESS && ]b4_c_modern[

 #     include <stdlib.h> /* INFRINGES ON USER NAME SPACE */
 #     include <stdlib.h> /* INFRINGES ON USER NAME SPACE */

-#     ifndef _STDLIB_H
-#      define _STDLIB_H 1
+#     ifndef EXIT_SUCCESS
+#      define EXIT_SUCCESS 0

 #     endif
 #    endif
 #   endif
 #     endif
 #    endif
 #   endif


@@ -447,23 +446,23 @@ typedef short int yytype_int16;
 #  ifndef YYSTACK_ALLOC_MAXIMUM
 #   define YYSTACK_ALLOC_MAXIMUM YYSIZE_MAXIMUM
 #  endif
 #  ifndef YYSTACK_ALLOC_MAXIMUM
 #   define YYSTACK_ALLOC_MAXIMUM YYSIZE_MAXIMUM
 #  endif

-#  if (defined __cplusplus && ! defined _STDLIB_H \
+#  if (defined __cplusplus && ! defined EXIT_SUCCESS \

        && ! ((defined YYMALLOC || defined malloc) \
             && (defined YYFREE || defined free)))
 #   include <stdlib.h> /* INFRINGES ON USER NAME SPACE */
        && ! ((defined YYMALLOC || defined malloc) \
             && (defined YYFREE || defined free)))
 #   include <stdlib.h> /* INFRINGES ON USER NAME SPACE */

-#   ifndef _STDLIB_H
-#    define _STDLIB_H 1
+#   ifndef EXIT_SUCCESS
+#    define EXIT_SUCCESS 0

 #   endif
 #  endif
 #  ifndef YYMALLOC
 #   define YYMALLOC malloc
 #   endif
 #  endif
 #  ifndef YYMALLOC
 #   define YYMALLOC malloc

-#   if ! defined malloc && ! defined _STDLIB_H && ]b4_c_modern[
+#   if ! defined malloc && ! defined EXIT_SUCCESS && ]b4_c_modern[

 void *malloc (YYSIZE_T); /* INFRINGES ON USER NAME SPACE */
 #   endif
 #  endif
 #  ifndef YYFREE
 #   define YYFREE free
 void *malloc (YYSIZE_T); /* INFRINGES ON USER NAME SPACE */
 #   endif
 #  endif
 #  ifndef YYFREE
 #   define YYFREE free

-#   if ! defined free && ! defined _STDLIB_H && ]b4_c_modern[
+#   if ! defined free && ! defined EXIT_SUCCESS && ]b4_c_modern[

 void free (void *); /* INFRINGES ON USER NAME SPACE */
 #   endif
 #  endif
 void free (void *); /* INFRINGES ON USER NAME SPACE */
 #   endif
 #  endif


@@ -630,7 +629,6 @@ do                                                          \
     {                                                          \
       yychar = (Token);                                                \
       yylval = (Value);                                                \
     {                                                          \
       yychar = (Token);                                                \
       yylval = (Value);                                                \

-      yytoken = YYTRANSLATE (yychar);                          \

       YYPOPSTACK (1);                                          \
       goto yybackup;                                           \
     }                                                          \
       YYPOPSTACK (1);                                          \
       goto yybackup;                                           \
     }                                                          \


@@ -1429,6 +1427,17 @@ yyreduce:
       ]b4_user_actions[
       default: break;
     }
       ]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);
   YY_SYMBOL_PRINT ("-> $$ =", yyr1[yyn], &yyval, &yyloc);
 
   YYPOPSTACK (yylen);


@@ -1457,6 +1466,10 @@ yyreduce:
 | yyerrlab -- here on detecting error |
 `------------------------------------*/
 yyerrlab:
 | 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)
     {
   /* If not already recovering from an error, report this error.  */
   if (!yyerrstatus)
     {


@@ -1464,32 +1477,38 @@ yyerrlab:
 #if ! YYERROR_VERBOSE
       yyerror (]b4_yyerror_args[YY_("syntax error"));
 #else
 #if ! YYERROR_VERBOSE
       yyerror (]b4_yyerror_args[YY_("syntax error"));
 #else

-      while (1)
-        {
-          int yysyntax_error_status =
-            yysyntax_error (&yymsg_alloc, &yymsg, yystate, yytoken);
-          if (yysyntax_error_status == 2 && 0 < yymsg_alloc)
-            {
-              if (yymsg != yymsgbuf)
-                YYSTACK_FREE (yymsg);
-              yymsg = (char *) YYSTACK_ALLOC (yymsg_alloc);
-              if (yymsg)
-                continue;
-              yymsg = yymsgbuf;
-              yymsg_alloc = sizeof yymsgbuf;
-            }
-          if (yysyntax_error_status == 0)
-            yyerror (]b4_yyerror_args[yymsg);
-          else
-            yyerror (]b4_yyerror_args[YY_("syntax error"));
-          if (yysyntax_error_status == 2)
-            goto yyexhaustedlab;
-          break;
-        }
+# define YYSYNTAX_ERROR yysyntax_error (&yymsg_alloc, &yymsg, yystate, \
+                                        yytoken)
+      {
+        char const *yymsgp = YY_("syntax error");
+        int yysyntax_error_status = YYSYNTAX_ERROR;
+        if (yysyntax_error_status == 0)
+          yymsgp = yymsg;
+        else if (yysyntax_error_status == 2 && 0 < yymsg_alloc)
+          {
+            if (yymsg != yymsgbuf)
+              YYSTACK_FREE (yymsg);
+            yymsg = (char *) YYSTACK_ALLOC (yymsg_alloc);
+            if (!yymsg)
+              {
+                yymsg = yymsgbuf;
+                yymsg_alloc = sizeof yymsgbuf;
+              }
+            else
+              {
+                yysyntax_error_status = YYSYNTAX_ERROR;
+                yymsgp = yymsg;
+              }
+          }
+        yyerror (]b4_yyerror_args[yymsgp);
+        if (yysyntax_error_status == 2)
+          goto yyexhaustedlab;
+      }
+# undef YYSYNTAX_ERROR

 #endif
     }
 
 #endif
     }
 

-]b4_locations_if([[  yyerror_range[0] = yylloc;]])[
+]b4_locations_if([[  yyerror_range[1] = yylloc;]])[

 
   if (yyerrstatus == 3)
     {
 
   if (yyerrstatus == 3)
     {


@@ -1526,7 +1545,7 @@ yyerrorlab:
   if (/*CONSTCOND*/ 0)
      goto yyerrorlab;
 
   if (/*CONSTCOND*/ 0)
      goto yyerrorlab;
 

-]b4_locations_if([[  yyerror_range[0] = yylsp[1-yylen];
+]b4_locations_if([[  yyerror_range[1] = yylsp[1-yylen];

 ]])[  /* Do not reclaim the symbols of the rule which action triggered
      this YYERROR.  */
   YYPOPSTACK (yylen);
 ]])[  /* Do not reclaim the symbols of the rule which action triggered
      this YYERROR.  */
   YYPOPSTACK (yylen);


@@ -1560,7 +1579,7 @@ yyerrlab1:
       if (yyssp == yyss)
        YYABORT;
 
       if (yyssp == yyss)
        YYABORT;
 

-]b4_locations_if([[      yyerror_range[0] = *yylsp;]])[
+]b4_locations_if([[      yyerror_range[1] = *yylsp;]])[

       yydestruct ("Error: popping",
                  yystos[yystate], yyvsp]b4_locations_if([, yylsp])[]b4_user_args[);
       YYPOPSTACK (1);
       yydestruct ("Error: popping",
                  yystos[yystate], yyvsp]b4_locations_if([, yylsp])[]b4_user_args[);
       YYPOPSTACK (1);


@@ -1570,10 +1589,10 @@ yyerrlab1:
 
   *++yyvsp = yylval;
 ]b4_locations_if([[
 
   *++yyvsp = yylval;
 ]b4_locations_if([[

-  yyerror_range[1] = yylloc;
+  yyerror_range[2] = yylloc;

   /* Using YYLLOC is tempting, but would change the location of
      the lookahead.  YYLOC is available though.  */
   /* Using YYLLOC is tempting, but would change the location of
      the lookahead.  YYLOC is available though.  */

-  YYLLOC_DEFAULT (yyloc, (yyerror_range - 1), 2);
+  YYLLOC_DEFAULT (yyloc, yyerror_range, 2);

   *++yylsp = yyloc;]])[
 
   /* Shift the error token.  */
   *++yylsp = yyloc;]])[
 
   /* Shift the error token.  */


@@ -1609,8 +1628,13 @@ yyexhaustedlab:
 
 yyreturn:
   if (yychar != YYEMPTY)
 
 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);
   /* Do not reclaim the symbols of the rule which action triggered
      this YYABORT or YYACCEPT.  */
   YYPOPSTACK (yylen);