02-popped-symbols.patch

[Akim Demaille]

Index: ChangeLog
from  Akim Demaille  <address@hidden>

        * tests/calc.at (AT_CHECK_CALC): Adjust: there are now additional
        `Error:' lines.
        * data/bison.simple (yystos) [YYDEBUG]: New.
        (yyparse) [YYDEBUG]: Display the symbols which are popped during
        error recovery.
        * tests/regression.at (Web2c Actions): Adjust: yystos is output now.

Index: NEWS
--- NEWS Sat, 25 May 2002 19:19:52 +0200 akim
+++ NEWS Sun, 26 May 2002 20:26:19 +0200 akim
@@ -26,6 +26,9 @@
   and has long been required by POSIX.  For more details, please see
   <http://mail.gnu.org/pipermail/bug-bison/2002-May/001452.html>.

+* Traces
+  Popped tokens and nonterminals are now reported.
+
 * Large grammars
   Large grammars are now supported (large token numbers, large grammar
   size (= sum of the LHS and RHS lengths), large LALR tables).
Index: data/bison.simple
--- data/bison.simple Sat, 25 May 2002 19:19:52 +0200 akim
+++ data/bison.simple Sun, 26 May 2002 20:15:40 +0200 akim
@@ -362,7 +362,7 @@ m4_define([b4_token_defines],
 };
 #endif

-#if (YYDEBUG) || YYERROR_VERBOSE
+#if YYDEBUG || YYERROR_VERBOSE
 /* YYTNME[[SYMBOL-NUM]] -- String name of the symbol SYMBOL-NUM.
    First, the terminals, then, starting at YYNTOKENS, nonterminals. */
 static const char *const yytname[[]] =
@@ -389,9 +389,9 @@ m4_define([b4_token_defines],
   b4_r2
 };

-/* YYDEFACT[[S]] -- default rule to reduce with in state S when YYTABLE
-   doesn't specify something else to do.  Zero means the default is an
-   error.  */
+/* YYDEFACT[[STATE-NAME]] -- Default rule to reduce with in state
+   STATE-NUM when YYTABLE doesn't specify something else to do.  Zero
+   means the default is an error.  */
 static const short yydefact[[]] =
 {
   b4_defact
@@ -429,6 +429,14 @@ m4_define([b4_token_defines],
   b4_check
 };

+#if YYDEBUG
+/* YYSTOS[[STATE-NUM]] -- The (internal number of the) accessing
+   symbol of state STATE-NUM.  */
+static const b4_uint_type(b4_stos_max) yystos[[]] =
+{
+  b4_stos
+};
+#endif

 #if ! defined (YYSIZE_T) && defined (__SIZE_TYPE__)
 # define YYSIZE_T __SIZE_TYPE__
@@ -1137,6 +1145,27 @@ yyerrlab1:
       /* Pop the current state because it cannot handle the error token.  */
       if (yyssp == yyss)
        YYABORT;
+
+#if YYDEBUG
+      if (yydebug)
+       {
+         if (yystos[yystate] < YYNTOKENS)
+           {
+             YYFPRINTF (stderr, "Error: popping token %d (%s",
+                        yytoknum[yystos[yystate]], yytname[yystos[yystate]]);
+# ifdef YYPRINT
+             YYPRINT (stderr, yytoknum[yystos[yystate]], *yyvsp);
+# endif
+             YYFPRINTF (stderr, ")\n");
+           }
+         else
+           {
+             YYFPRINTF (stderr, "Error: popping nonterminal (%s)\n",
+                        yytname[yystos[yystate]]);
+           }
+       }
+#endif
+
       yyvsp--;
       yystate = *--yyssp;
 #if YYLSP_NEEDED
Index: tests/calc.at
--- tests/calc.at Wed, 01 May 2002 11:49:53 +0200 akim
+++ tests/calc.at Sun, 26 May 2002 20:24:13 +0200 akim
@@ -1,5 +1,5 @@
 # Checking the output filenames.                         -*- Autotest -*-
-# Copyright 2000, 2001 Free Software Foundation, Inc.
+# Copyright (C) 2000, 2001, 2002 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
@@ -406,18 +406,18 @@ m4_define([AT_CHECK_CALC],
 (2^2)^3 = 64], [486])

 # Some parse errors.
-_AT_CHECK_CALC_ERROR([$1], [0 0], [10],
+_AT_CHECK_CALC_ERROR([$1], [0 0], [11],
                      [1.3-1.4: parse error, unexpected "number"])
-_AT_CHECK_CALC_ERROR([$1], [1//2], [13],
+_AT_CHECK_CALC_ERROR([$1], [1//2], [15],
                      [1.3-1.4: parse error, unexpected '/', expecting "number" 
or '-' or '('])
 _AT_CHECK_CALC_ERROR([$1], [error], [4],
                      [1.1-1.2: parse error, unexpected $undefined., expecting 
"number" or '-' or '\n' or '('])
-_AT_CHECK_CALC_ERROR([$1], [1 = 2 = 3], [19],
+_AT_CHECK_CALC_ERROR([$1], [1 = 2 = 3], [22],
                      [1.7-1.8: parse error, unexpected '='])
 _AT_CHECK_CALC_ERROR([$1],
                      [
 +1],
-                     [13],
+                     [14],
                      [2.1-2.2: parse error, unexpected '+'])
 # Exercise error messages with EOF: work on an empty file.
 _AT_CHECK_CALC_ERROR([$1],
@@ -430,7 +430,7 @@ m4_define([AT_CHECK_CALC],
 # associated to `error'.
 _AT_CHECK_CALC_ERROR([$1],
                      [(1 ++ 2) + (0 0) = 1],
-                     [76],
+                     [82],
 [1.5-1.6: parse error, unexpected '+', expecting "number" or '-' or '('
 1.15-1.16: parse error, unexpected "number"
 calc: error: 0 != 1])
Index: tests/regression.at
--- tests/regression.at Sat, 25 May 2002 19:19:52 +0200 akim
+++ tests/regression.at Sun, 26 May 2002 20:20:55 +0200 akim
@@ -1,5 +1,5 @@
 # Bison Regressions.                               -*- Autotest -*-
-# Copyright 2001, 2002 Free Software Foundation, Inc.
+# Copyright (C) 2001, 2002 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
@@ -548,6 +548,11 @@ else: "else" statement;
 static const short yycheck[] =
 {
        7,     3,     9,     4,     0,    -1,     6,     5
+};
+static const unsigned char yystos[] =
+{
+       0,     3,     8,     9,    10,     4,     0,     6,    11,     5,
+       8,     8
 };
 ]])