Inform m4 whether a tag is a valid id.

[bison.git] / src / output.c

diff --git a/src/output.c b/src/output.c
index 4608a2fa58b7110351e6188793cde039561f2860..afcec94956b05cce53ea896b3533438c82c5d076 100644 (file)
--- a/src/output.c
+++ b/src/output.c
@@ -1,24 +1,22 @@
 /* Output the generated parsing program for Bison.
 
    Copyright (C) 1984, 1986, 1989, 1992, 2000, 2001, 2002, 2003, 2004,
 /* Output the generated parsing program for Bison.
 
    Copyright (C) 1984, 1986, 1989, 1992, 2000, 2001, 2002, 2003, 2004,

-   2005, 2006 Free Software Foundation, Inc.
+   2005, 2006, 2007, 2008 Free Software Foundation, Inc.

 
    This file is part of Bison, the GNU Compiler Compiler.
 
 
    This file is part of Bison, the GNU Compiler Compiler.
 

-   Bison is free software; you can redistribute it and/or modify it
-   under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2, or (at your option)
-   any later version.
+   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
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.

 
 

-   Bison is distributed in the hope that it will be useful, but
-   WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   General Public License for more details.
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.

 
    You should have received a copy of the GNU General Public License
 
    You should have received a copy of the GNU General Public License

-   along with Bison; see the file COPYING.  If not, write to the Free
-   Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
-   02110-1301, USA.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

 
 #include <config.h>
 #include "system.h"
 
 #include <config.h>
 #include "system.h"


@@ -145,6 +143,7 @@ prepare_symbols (void)
   MUSCLE_INSERT_BOOL ("token_table", token_table_flag);
   MUSCLE_INSERT_INT ("tokens_number", ntokens);
   MUSCLE_INSERT_INT ("nterms_number", nvars);
   MUSCLE_INSERT_BOOL ("token_table", token_table_flag);
   MUSCLE_INSERT_INT ("tokens_number", ntokens);
   MUSCLE_INSERT_INT ("nterms_number", nvars);

+  MUSCLE_INSERT_INT ("symbols_number", nsyms);

   MUSCLE_INSERT_INT ("undef_token_number", undeftoken->number);
   MUSCLE_INSERT_INT ("user_token_number_max", max_user_token_number);
 
   MUSCLE_INSERT_INT ("undef_token_number", undeftoken->number);
   MUSCLE_INSERT_INT ("user_token_number_max", max_user_token_number);
 


@@ -158,9 +157,12 @@ prepare_symbols (void)
     int i;
     /* We assume that the table will be output starting at column 2. */
     int j = 2;
     int i;
     /* We assume that the table will be output starting at column 2. */
     int j = 2;

+    struct quoting_options *qo = clone_quoting_options (0);
+    set_quoting_style (qo, c_quoting_style);
+    set_quoting_flags (qo, QA_SPLIT_TRIGRAPHS);

     for (i = 0; i < nsyms; i++)
       {
     for (i = 0; i < nsyms; i++)
       {

-       char const *cp = quotearg_style (c_quoting_style, symbols[i]->tag);
+       char *cp = quotearg_alloc (symbols[i]->tag, -1, qo);

        /* Width of the next token, including the two quotes, the
           comma and the space.  */
        int width = strlen (cp) + 2;
        /* Width of the next token, including the two quotes, the
           comma and the space.  */
        int width = strlen (cp) + 2;


@@ -174,9 +176,11 @@ prepare_symbols (void)
        if (i)
          obstack_1grow (&format_obstack, ' ');
        MUSCLE_OBSTACK_SGROW (&format_obstack, cp);
        if (i)
          obstack_1grow (&format_obstack, ' ');
        MUSCLE_OBSTACK_SGROW (&format_obstack, cp);

+        free (cp);

        obstack_1grow (&format_obstack, ',');
        j += width;
       }
        obstack_1grow (&format_obstack, ',');
        j += width;
       }

+    free (qo);

     obstack_sgrow (&format_obstack, " ]b4_null[");
 
     /* Finish table and store. */
     obstack_sgrow (&format_obstack, " ]b4_null[");
 
     /* Finish table and store. */


@@ -279,6 +283,73 @@ prepare_states (void)
 }
 
 
 }
 
 

+/*-------------------------------------------------------.
+| Compare two symbols by type-name, and then by number.  |
+`-------------------------------------------------------*/
+
+int
+symbol_type_name_cmp (const symbol **lhs, const symbol **rhs)
+{
+  int res = UNIQSTR_CMP((*lhs)->type_name, (*rhs)->type_name);
+  if (res)
+    return res;
+  return (*lhs)->number - (*rhs)->number;
+}
+
+
+/*----------------------------------------------------------------.
+| Return a (malloc'ed) table of the symbols sorted by type-name.  |
+`----------------------------------------------------------------*/
+
+static symbol **
+symbols_by_type_name ()
+{
+  typedef int (*qcmp_type) (const void *, const void *);
+  symbol **res = xmemdup (symbols, nsyms * sizeof *res);
+  qsort (res, nsyms, sizeof *res, (qcmp_type) &symbol_type_name_cmp);
+  return res;
+}
+
+
+/*------------------------------------------------------------------.
+| Define b4_type_names, which is a list of (lists of the numbers of |
+| symbols with same type-name).                                     |
+`------------------------------------------------------------------*/
+
+static void
+type_names_output (FILE *out)
+{
+  int i;
+  symbol **syms = symbols_by_type_name ();
+  fputs ("m4_define([b4_type_names],\n[", out);
+  for (i = 0; i < nsyms; /* nothing */)
+    {
+      // The index of the first symbol of the current type-name.
+      int i0 = i;
+      fputs (i ? ",\n[" : "[", out);
+      for (; i < nsyms && syms[i]->type_name == syms[i0]->type_name; ++i)
+        fprintf (out, "%s%d", i != i0 ? ", " : "", syms[i]->number);
+      fputs ("]", out);
+    }
+  fputs ("])\n\n", out);
+  free (syms);
+}
+
+
+/*-------------------------------------.
+| The list of all the symbol numbers.  |
+`-------------------------------------*/
+
+static void
+symbol_numbers_output (FILE *out)
+{
+  int i;
+  fputs ("m4_define([b4_symbol_numbers],\n[", out);
+  for (i = 0; i < nsyms; ++i)
+    fprintf (out, "%s[%d]", i ? ", " : "", i);
+  fputs ("])\n\n", out);
+}
+

 
 /*---------------------------------.
 | Output the user actions to OUT.  |
 
 /*---------------------------------.
 | Output the user actions to OUT.  |


@@ -301,9 +372,9 @@ user_actions_output (FILE *out)
   fputs ("])\n\n", out);
 }
 
   fputs ("])\n\n", out);
 }
 

-/*--------------------------------------.
-| Output the merge functions to OUT.   |
-`--------------------------------------*/
+/*------------------------------------.
+| Output the merge functions to OUT.  |
+`------------------------------------*/

 
 static void
 merger_output (FILE *out)
 
 static void
 merger_output (FILE *out)


@@ -324,6 +395,74 @@ merger_output (FILE *out)
   fputs ("]])\n\n", out);
 }
 
   fputs ("]])\n\n", out);
 }
 

+
+/*----------------------------------.
+| Whether S is a valid identifier.  |
+`----------------------------------*/
+
+static bool
+is_identifier (uniqstr s)
+{
+  static char const alphanum[26 + 26 + 1 + 10] =
+    "abcdefghijklmnopqrstuvwxyz"
+    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+    "_"
+    "0123456789";
+  if (!s || ! memchr (alphanum, *s, sizeof alphanum - 10))
+    return false;
+  for (++s; *s; ++s)
+    if (! memchr (alphanum, *s, sizeof alphanum))
+      return false;
+  return true;
+}
+
+/*---------------------------------------.
+| Output the symbol definitions to OUT.  |
+`---------------------------------------*/
+
+static void
+symbol_definitions_output (FILE *out)
+{
+  int i;
+  for (i = 0; i < nsyms; ++i)
+    {
+      symbol *sym = symbols[i];
+      const char *key;
+
+#define SET_KEY(Entry)                                                  \
+      obstack_fgrow2 (&format_obstack, "symbol(%d, %s)", i, Entry);     \
+      obstack_1grow (&format_obstack, 0);                               \
+      key = obstack_finish (&format_obstack);
+
+      // Whether the tag is a valid identifier.
+      SET_KEY("tag_is_id");
+      MUSCLE_INSERT_INT (key, is_identifier(sym->tag));
+
+      // The inner tag.
+      SET_KEY("tag");
+      MUSCLE_INSERT_STRING (key, sym->tag);
+
+      SET_KEY("user_number");
+      MUSCLE_INSERT_INT (key, sym->user_token_number);
+
+      SET_KEY("is_token");
+      MUSCLE_INSERT_INT (key,
+                         i < ntokens && sym != errtoken && sym != undeftoken);
+
+      SET_KEY("number");
+      MUSCLE_INSERT_INT (key, sym->number);
+
+      SET_KEY("has_type_name");
+      MUSCLE_INSERT_INT (key, !!sym->type_name);
+
+      SET_KEY("type_name");
+      MUSCLE_INSERT_STRING (key, sym->type_name ? sym->type_name : "");
+
+#undef SET_KEY
+    }
+}
+
+

 /*--------------------------------------.
 | Output the tokens definition to OUT.  |
 `--------------------------------------*/
 /*--------------------------------------.
 | Output the tokens definition to OUT.  |
 `--------------------------------------*/


@@ -373,70 +512,41 @@ token_definitions_output (FILE *out)
 }
 
 
 }
 
 

-/*---------------------------------------.
-| Output the symbol destructors to OUT.  |
-`---------------------------------------*/
-
-static void
-symbol_destructors_output (FILE *out)
-{
-  int i;
-  char const *sep = "";
-
-  fputs ("m4_define([b4_symbol_destructors], \n[", out);
-  for (i = 0; i < nsyms; ++i)
-    if (symbol_destructor_get (symbols[i]))
-      {
-       symbol *sym = symbols[i];
-
-       /* Filename, lineno,
-          Symbol-name, Symbol-number,
-          destructor, optional typename.  */
-       fprintf (out, "%s[", sep);
-       sep = ",\n";
-       escaped_output (out, symbol_destructor_location_get (sym).start.file);
-       fprintf (out, ", %d, ",
-                symbol_destructor_location_get (sym).start.line);
-       escaped_output (out, sym->tag);
-       fprintf (out, ", %d, [[%s]]", sym->number,
-                symbol_destructor_get (sym));
-       if (sym->type_name)
-         fprintf (out, ", [[%s]]", sym->type_name);
-       fputc (']', out);
-      }
-  fputs ("])\n\n", out);
-}
-
-
-/*------------------------------------.
-| Output the symbol printers to OUT.  |
-`------------------------------------*/
+/*---------------------------------------------------.
+| Output the symbol destructors or printers to OUT.  |
+`---------------------------------------------------*/

 
 static void
 
 static void

-symbol_printers_output (FILE *out)
+symbol_code_props_output (FILE *out, char const *what,
+                          code_props const *(*get)(symbol const *))

 {
   int i;
   char const *sep = "";
 
 {
   int i;
   char const *sep = "";
 

-  fputs ("m4_define([b4_symbol_printers], \n[", out);
+  fputs ("m4_define([b4_symbol_", out);
+  fputs (what, out);
+  fputs ("], \n[", out);

   for (i = 0; i < nsyms; ++i)
   for (i = 0; i < nsyms; ++i)

-    if (symbol_printer_get (symbols[i]))
-      {
-       symbol *sym = symbols[i];
-
-       /* Filename, lineno,
-          Symbol-name, Symbol-number,
-          printer, optional typename.  */
-       fprintf (out, "%s[", sep);
-       sep = ",\n";
-       escaped_output (out, symbol_printer_location_get (sym).start.file);
-       fprintf (out, ", %d, ", symbol_printer_location_get (sym).start.line);
-       escaped_output (out, sym->tag);
-       fprintf (out, ", %d, [[%s]]", sym->number, symbol_printer_get (sym));
-       if (sym->type_name)
-         fprintf (out, ", [[%s]]", sym->type_name);
-       fputc (']', out);
-      }
+    {
+      symbol *sym = symbols[i];
+      char const *code = (*get) (sym)->code;
+      if (code)
+        {
+          location loc = (*get) (sym)->location;
+          /* Filename, lineno,
+             Symbol-name, Symbol-number,
+             code, optional typename.  */
+          fprintf (out, "%s[", sep);
+          sep = ",\n";
+          escaped_output (out, loc.start.file);
+          fprintf (out, ", %d, ", loc.start.line);
+          escaped_output (out, sym->tag);
+          fprintf (out, ", %d, [[%s]]", sym->number, code);
+          if (sym->type_name)
+            fprintf (out, ", [[%s]]", sym->type_name);
+          fputc (']', out);
+        }
+    }

   fputs ("])\n\n", out);
 }
 
   fputs ("])\n\n", out);
 }
 


@@ -488,6 +598,26 @@ prepare_actions (void)
                                    0, 1, conflict_list_cnt);
 }
 
                                    0, 1, conflict_list_cnt);
 }
 

+
+/*--------------------------------------------.
+| Output the definitions of all the muscles.  |
+`--------------------------------------------*/
+
+static void
+muscles_output (FILE *out)
+{
+  fputs ("m4_init()\n", out);
+  merger_output (out);
+  symbol_code_props_output (out, "destructors", &symbol_destructor_get);
+  symbol_code_props_output (out, "printers", &symbol_printer_get);
+  symbol_definitions_output (out);
+  symbol_numbers_output (out);
+  token_definitions_output (out);
+  type_names_output (out);
+  user_actions_output (out);
+  // Must be last.
+  muscles_m4_output (out);
+}

 \f
 /*---------------------------.
 | Call the skeleton parser.  |
 \f
 /*---------------------------.
 | Call the skeleton parser.  |


@@ -497,15 +627,11 @@ static void
 output_skeleton (void)
 {
   FILE *in;
 output_skeleton (void)
 {
   FILE *in;

-  FILE *out;

   int filter_fd[2];
   int filter_fd[2];

-  char const *argv[7];
+  char const *argv[9];

   pid_t pid;
 
   pid_t pid;
 

-  /* Compute the names of the package data dir and skeleton file.
-     Test whether m4sugar.m4 is readable, to check for proper
-     installation.  A faulty installation can cause deadlock, so a
-     cheap sanity check is worthwhile.  */
+  /* Compute the names of the package data dir and skeleton files.  */

   char const m4sugar[] = "m4sugar/m4sugar.m4";
   char const m4bison[] = "bison.m4";
   char *full_m4sugar;
   char const m4sugar[] = "m4sugar/m4sugar.m4";
   char const m4bison[] = "bison.m4";
   char *full_m4sugar;


@@ -513,7 +639,7 @@ output_skeleton (void)
   char *full_skeleton;
   char const *p;
   char const *m4 = (p = getenv ("M4")) ? p : M4;
   char *full_skeleton;
   char const *p;
   char const *m4 = (p = getenv ("M4")) ? p : M4;

-  char const *pkgdatadir = (p = getenv ("BISON_PKGDATADIR")) ? p : PKGDATADIR;
+  char const *pkgdatadir = compute_pkgdatadir ();

   size_t skeleton_size = strlen (skeleton) + 1;
   size_t pkgdatadirlen = strlen (pkgdatadir);
   while (pkgdatadirlen && pkgdatadir[pkgdatadirlen - 1] == '/')
   size_t skeleton_size = strlen (skeleton) + 1;
   size_t pkgdatadirlen = strlen (pkgdatadir);
   while (pkgdatadirlen && pkgdatadir[pkgdatadirlen - 1] == '/')


@@ -521,54 +647,83 @@ output_skeleton (void)
   full_skeleton = xmalloc (pkgdatadirlen + 1
                           + (skeleton_size < sizeof m4sugar
                              ? sizeof m4sugar : skeleton_size));
   full_skeleton = xmalloc (pkgdatadirlen + 1
                           + (skeleton_size < sizeof m4sugar
                              ? sizeof m4sugar : skeleton_size));

-  strcpy (full_skeleton, pkgdatadir);
+  strncpy (full_skeleton, pkgdatadir, pkgdatadirlen);

   full_skeleton[pkgdatadirlen] = '/';
   strcpy (full_skeleton + pkgdatadirlen + 1, m4sugar);
   full_m4sugar = xstrdup (full_skeleton);
   strcpy (full_skeleton + pkgdatadirlen + 1, m4bison);
   full_m4bison = xstrdup (full_skeleton);
   full_skeleton[pkgdatadirlen] = '/';
   strcpy (full_skeleton + pkgdatadirlen + 1, m4sugar);
   full_m4sugar = xstrdup (full_skeleton);
   strcpy (full_skeleton + pkgdatadirlen + 1, m4bison);
   full_m4bison = xstrdup (full_skeleton);

-  strcpy (full_skeleton + pkgdatadirlen + 1, skeleton);
+  if (strchr (skeleton, '/'))
+    strcpy (full_skeleton, skeleton);
+  else
+    strcpy (full_skeleton + pkgdatadirlen + 1, skeleton);
+
+  /* Test whether m4sugar.m4 is readable, to check for proper
+     installation.  A faulty installation can cause deadlock, so a
+     cheap sanity check is worthwhile.  */

   xfclose (xfopen (full_m4sugar, "r"));
 
   /* Create an m4 subprocess connected to us via two pipes.  */
 
   if (trace_flag & trace_tools)
     fprintf (stderr, "running: %s %s - %s %s\n",
   xfclose (xfopen (full_m4sugar, "r"));
 
   /* Create an m4 subprocess connected to us via two pipes.  */
 
   if (trace_flag & trace_tools)
     fprintf (stderr, "running: %s %s - %s %s\n",

-            m4, full_m4sugar, full_m4bison, full_skeleton);
+             m4, full_m4sugar, full_m4bison, full_skeleton);

 
 

-  argv[0] = m4;
-  argv[1] = full_m4sugar;
-  argv[2] = "-";
-  argv[3] = full_m4bison;
-  argv[4] = full_skeleton;
-  argv[5] = trace_flag & trace_m4 ? "-dV" : NULL;
-  argv[6] = NULL;
+  /* Some future version of GNU M4 (most likely 1.6) may treat the -dV in a
+     position-dependent manner.  Keep it as the first argument so that all
+     files are traced.

 
 

+     See the thread starting at
+     <http://lists.gnu.org/archive/html/bug-bison/2008-07/msg00000.html>
+     for details.  */
+  {
+    int i = 0;
+    argv[i++] = m4;
+    argv[i++] = "-I";
+    argv[i++] = pkgdatadir;
+    if (trace_flag & trace_m4)
+      argv[i++] = "-dV";
+    argv[i++] = full_m4sugar;
+    argv[i++] = "-";
+    argv[i++] = full_m4bison;
+    argv[i++] = full_skeleton;
+    argv[i++] = NULL;
+  }
+  /* When POSIXLY_CORRECT is set, some future versions of GNU M4 (most likely
+     2.0) may drop some of the GNU extensions that Bison's skeletons depend
+     upon.  So that the next release of Bison is forward compatible with those
+     future versions of GNU M4, we unset POSIXLY_CORRECT here.
+
+     FIXME: A user might set POSIXLY_CORRECT to affect processes run from
+     macros like m4_syscmd in a custom skeleton.  For now, Bison makes no
+     promises about the behavior of custom skeletons, so this scenario is not a
+     concern.  However, we eventually want to eliminate this shortcoming.  The
+     next release of GNU M4 (1.4.12 or 1.6) will accept the -g command-line
+     option as a no-op, and later releases will accept it to indicate that
+     POSIXLY_CORRECT should be ignored.  Once the GNU M4 versions that accept
+     -g are pervasive, Bison should use -g instead of unsetting
+     POSIXLY_CORRECT.
+
+     See the thread starting at
+     <http://lists.gnu.org/archive/html/bug-bison/2008-07/msg00000.html>
+     for details.  */
+  unsetenv ("POSIXLY_CORRECT");

   init_subpipe ();
   pid = create_subpipe (argv, filter_fd);
   init_subpipe ();
   pid = create_subpipe (argv, filter_fd);

-  free (full_m4bison);

   free (full_m4sugar);
   free (full_m4sugar);

+  free (full_m4bison);

   free (full_skeleton);
 
   free (full_skeleton);
 

-  out = fdopen (filter_fd[0], "w");
-  if (! out)
-    error (EXIT_FAILURE, get_errno (),
-          "fdopen");
-
-  /* Output the definitions of all the muscles.  */
-  fputs ("m4_init()\n", out);
-
-  user_actions_output (out);
-  merger_output (out);
-  token_definitions_output (out);
-  symbol_destructors_output (out);
-  symbol_printers_output (out);
-
-  muscles_m4_output (out);
-
-  fputs ("m4_wrap([m4_divert_pop(0)])\n", out);
-  fputs ("m4_divert_push(0)dnl\n", out);
-  xfclose (out);
+  if (trace_flag & trace_muscles)
+    muscles_output (stderr);
+  {
+    FILE *out = fdopen (filter_fd[0], "w");
+    if (! out)
+      error (EXIT_FAILURE, get_errno (),
+             "fdopen");
+    muscles_output (out);
+    xfclose (out);
+  }

 
   /* Read and process m4's output.  */
   timevar_push (TV_M4);
 
   /* Read and process m4's output.  */
   timevar_push (TV_M4);


@@ -586,6 +741,15 @@ output_skeleton (void)
 static void
 prepare (void)
 {
 static void
 prepare (void)
 {

+  /* BISON_USE_PUSH_FOR_PULL is for the test suite and should not be documented
+     for the user.  */
+  char const *use_push_for_pull_env = getenv ("BISON_USE_PUSH_FOR_PULL");
+  bool use_push_for_pull_flag = false;
+  if (use_push_for_pull_env != NULL
+      && use_push_for_pull_env[0] != '\0'
+      && 0 != strcmp (use_push_for_pull_env, "0"))
+    use_push_for_pull_flag = true;
+

   /* Flags. */
   MUSCLE_INSERT_BOOL ("debug_flag", debug_flag);
   MUSCLE_INSERT_BOOL ("defines_flag", defines_flag);
   /* Flags. */
   MUSCLE_INSERT_BOOL ("debug_flag", debug_flag);
   MUSCLE_INSERT_BOOL ("defines_flag", defines_flag);


@@ -593,10 +757,9 @@ prepare (void)
   MUSCLE_INSERT_BOOL ("glr_flag", glr_parser);
   MUSCLE_INSERT_BOOL ("locations_flag", locations_flag);
   MUSCLE_INSERT_BOOL ("nondeterministic_flag", nondeterministic_parser);
   MUSCLE_INSERT_BOOL ("glr_flag", glr_parser);
   MUSCLE_INSERT_BOOL ("locations_flag", locations_flag);
   MUSCLE_INSERT_BOOL ("nondeterministic_flag", nondeterministic_parser);

-  MUSCLE_INSERT_BOOL ("pure_flag", pure_parser);
-  MUSCLE_INSERT_BOOL ("push_flag", push_parser);

   MUSCLE_INSERT_BOOL ("synclines_flag", !no_lines_flag);
   MUSCLE_INSERT_BOOL ("tag_seen_flag", tag_seen);
   MUSCLE_INSERT_BOOL ("synclines_flag", !no_lines_flag);
   MUSCLE_INSERT_BOOL ("tag_seen_flag", tag_seen);

+  MUSCLE_INSERT_BOOL ("use_push_for_pull_flag", use_push_for_pull_flag);

   MUSCLE_INSERT_BOOL ("yacc_flag", yacc_flag);
 
   /* File names.  */
   MUSCLE_INSERT_BOOL ("yacc_flag", yacc_flag);
 
   /* File names.  */


@@ -616,12 +779,6 @@ prepare (void)
   DEFINE (spec_verbose_file);
 #undef DEFINE
 
   DEFINE (spec_verbose_file);
 #undef DEFINE
 

-  /* User Code.  */
-  obstack_1grow (&pre_prologue_obstack, 0);
-  obstack_1grow (&post_prologue_obstack, 0);
-  muscle_insert ("pre_prologue", obstack_finish (&pre_prologue_obstack));
-  muscle_insert ("post_prologue", obstack_finish (&post_prologue_obstack));
-

   /* Find the right skeleton file, and add muscles about the skeletons.  */
   if (skeleton)
     MUSCLE_INSERT_C_STRING ("skeleton", skeleton);
   /* Find the right skeleton file, and add muscles about the skeletons.  */
   if (skeleton)
     MUSCLE_INSERT_C_STRING ("skeleton", skeleton);


@@ -630,12 +787,10 @@ prepare (void)
 
   /* About the skeletons.  */
   {
 
   /* About the skeletons.  */
   {

-    char const *pkgdatadir = getenv ("BISON_PKGDATADIR");

     /* b4_pkgdatadir is used inside m4_include in the skeletons, so digraphs
        would never be expanded.  Hopefully no one has M4-special characters in
        his Bison installation path.  */
     /* b4_pkgdatadir is used inside m4_include in the skeletons, so digraphs
        would never be expanded.  Hopefully no one has M4-special characters in
        his Bison installation path.  */

-    MUSCLE_INSERT_STRING_RAW ("pkgdatadir",
-                              pkgdatadir ? pkgdatadir : PKGDATADIR);
+    MUSCLE_INSERT_STRING_RAW ("pkgdatadir", compute_pkgdatadir ());

   }
 }
 
   }
 }
 


@@ -660,6 +815,11 @@ output (void)
   output_skeleton ();
 
   obstack_free (&format_obstack, NULL);
   output_skeleton ();
 
   obstack_free (&format_obstack, NULL);

-  obstack_free (&pre_prologue_obstack, NULL);
-  obstack_free (&post_prologue_obstack, NULL);
+}
+
+char const *
+compute_pkgdatadir (void)
+{
+  char const *pkgdatadir = getenv ("BISON_PKGDATADIR");
+  return pkgdatadir ? pkgdatadir : PKGDATADIR;

 }
 }