Avoid empty-if warnings.

[bison.git] / src / scan-code.l

diff --git a/src/scan-code.l b/src/scan-code.l
index 4e464a7a8002f82ee5aecd30966730be8a6525aa..71c90768efb4700f2d52d888b4e3a9d604a075bc 100644 (file)
--- a/src/scan-code.l
+++ b/src/scan-code.l
@@ -1,12 +1,12 @@
 /* Bison Action Scanner                             -*- C -*-
 
 /* Bison Action Scanner                             -*- C -*-
 

-   Copyright (C) 2006 Free Software Foundation, Inc.
+   Copyright (C) 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.
 

-   This program is free software; you can redistribute it and/or modify
+   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
    it under the terms of the GNU General Public License as published by

-   the Free Software Foundation; either version 2 of the License, or
+   the Free Software Foundation, either version 3 of the License, or

    (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,


@@ -15,37 +15,32 @@
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
    GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License

-   along with this program; 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/>.  */

 
 %option debug nodefault nounput noyywrap never-interactive
 %option prefix="code_" outfile="lex.yy.c"
 
 %{
 
 %option debug nodefault nounput noyywrap never-interactive
 %option prefix="code_" outfile="lex.yy.c"
 
 %{

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

 /* Work around a bug in flex 2.5.31.  See Debian bug 333231
    <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333231>.  */
 #undef code_wrap
 #define code_wrap() 1
 
 #define FLEX_PREFIX(Id) code_ ## Id
 /* Work around a bug in flex 2.5.31.  See Debian bug 333231
    <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333231>.  */
 #undef code_wrap
 #define code_wrap() 1
 
 #define FLEX_PREFIX(Id) code_ ## Id

-#include "complain.h"

 #include "flex-scanner.h"
 #include "flex-scanner.h"

+
+#include "complain.h"

 #include "reader.h"
 #include "getargs.h"
 #include "reader.h"
 #include "getargs.h"

-#include <assert.h>

 #include <get-errno.h>
 #include <quote.h>
 
 #include "scan-code.h"
 #include <get-errno.h>
 #include <quote.h>
 
 #include "scan-code.h"

+#include "symlist.h"

 
 /* The current calling start condition: SC_RULE_ACTION or
    SC_SYMBOL_ACTION. */
 
 /* The current calling start condition: SC_RULE_ACTION or
    SC_SYMBOL_ACTION. */

-# define YY_DECL const char *code_lex (int sc_context, symbol_list *rule)
+# define YY_DECL static char *code_lex (code_props *self, int sc_context)

 YY_DECL;
 
 #define YY_USER_ACTION  location_compute (loc, &loc->end, yytext, yyleng);
 YY_DECL;
 
 #define YY_USER_ACTION  location_compute (loc, &loc->end, yytext, yyleng);


@@ -55,6 +50,12 @@ static void handle_action_dollar (symbol_list *rule, char *cp,
 static void handle_action_at (symbol_list *rule, char *cp, location at_loc);
 static location the_location;
 static location *loc = &the_location;
 static void handle_action_at (symbol_list *rule, char *cp, location at_loc);
 static location the_location;
 static location *loc = &the_location;

+
+/* A string representing the most recent translation.  */
+static char *last_string;
+
+/* True if an untyped $$ or $n was seen.  */
+static bool untyped_var_seen;

 %}
  /* C and C++ comments in code. */
 %x SC_COMMENT SC_LINE_COMMENT
 %}
  /* C and C++ comments in code. */
 %x SC_COMMENT SC_LINE_COMMENT


@@ -78,14 +79,14 @@ splice       (\\[ \f\t\v]*\n)*
 
 %{
   /* Nesting level of the current code in braces.  */
 
 %{
   /* Nesting level of the current code in braces.  */

-  int braces_level IF_LINT (= 0);
+  int braces_level = 0;

 
   /* This scanner is special: it is invoked only once, henceforth
      is expected to return only once.  This initialization is
      therefore done once per action to translate. */
 
   /* This scanner is special: it is invoked only once, henceforth
      is expected to return only once.  This initialization is
      therefore done once per action to translate. */

-  assert (sc_context == SC_SYMBOL_ACTION
-         || sc_context == SC_RULE_ACTION
-         || sc_context == INITIAL);
+  aver (sc_context == SC_SYMBOL_ACTION
+       || sc_context == SC_RULE_ACTION
+       || sc_context == INITIAL);

   BEGIN sc_context;
 %}
 
   BEGIN sc_context;
 %}
 


@@ -151,8 +152,12 @@ splice      (\\[ \f\t\v]*\n)*
 
 <SC_RULE_ACTION>
 {
 
 <SC_RULE_ACTION>
 {

-  "$"("<"{tag}">")?(-?[0-9]+|"$")   handle_action_dollar (rule, yytext, *loc);
-  "@"(-?[0-9]+|"$")                handle_action_at (rule, yytext, *loc);
+  "$"("<"{tag}">")?(-?[0-9]+|"$")  {
+    handle_action_dollar (self->rule, yytext, *loc);
+  }
+  "@"(-?[0-9]+|"$") {
+    handle_action_at (self->rule, yytext, *loc);
+  }

 
   "$"  {
     warn_at (*loc, _("stray `$'"));
 
   "$"  {
     warn_at (*loc, _("stray `$'"));


@@ -165,7 +170,7 @@ splice       (\\[ \f\t\v]*\n)*
 
   "{"  STRING_GROW; ++braces_level;
   "}"  {
 
   "{"  STRING_GROW; ++braces_level;
   "}"  {

-    bool outer_brace = --braces_level < 0;
+    bool outer_brace = --braces_level == 0;

 
     /* As an undocumented Bison extension, append `;' before the last
        brace in braced code, so that the user code can omit trailing
 
     /* As an undocumented Bison extension, append `;' before the last
        brace in braced code, so that the user code can omit trailing


@@ -190,8 +195,14 @@ splice      (\\[ \f\t\v]*\n)*
 
 <SC_SYMBOL_ACTION>
 {
 
 <SC_SYMBOL_ACTION>
 {

-  "$$"   obstack_sgrow (&obstack_for_string, "]b4_dollar_dollar[");
-  "@$"   obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");
+  "$$" {
+    obstack_sgrow (&obstack_for_string, "]b4_dollar_dollar[");
+    self->is_value_used = true;
+  }
+  "@$" {
+    obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");
+    locations_flag = true;
+  }

 }
 
 
 }
 
 


@@ -215,8 +226,8 @@ splice       (\\[ \f\t\v]*\n)*
 
  /* End of processing. */
 <*><<EOF>>      {
 
  /* End of processing. */
 <*><<EOF>>      {

-                   obstack_1grow (&obstack_for_string, '\0');
-                  return obstack_finish (&obstack_for_string);
+                   STRING_FINISH;
+                   return last_string;

                  }
 
 %%
                  }
 
 %%


@@ -238,9 +249,21 @@ int max_left_semantic_context = 0;
 static void
 handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)
 {
 static void
 handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)
 {

-  const char *type_name = NULL;
+  char const *type_name = NULL;

   char *cp = text + 1;
   char *cp = text + 1;

-  int rule_length = symbol_list_length (rule->next);
+  symbol_list *effective_rule;
+  int effective_rule_length;
+
+  if (rule->midrule_parent_rule)
+    {
+      effective_rule = rule->midrule_parent_rule;
+      effective_rule_length = rule->midrule_parent_rhs_index - 1;
+    }
+  else
+    {
+      effective_rule = rule;
+      effective_rule_length = symbol_list_length (rule->next);
+    }

 
   /* Get the type name if explicit. */
   if (*cp == '<')
 
   /* Get the type name if explicit. */
   if (*cp == '<')


@@ -250,43 +273,68 @@ handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)
        ++cp;
       *cp = '\0';
       ++cp;
        ++cp;
       *cp = '\0';
       ++cp;

+      if (untyped_var_seen)
+       complain_at (dollar_loc, _("explicit type given in untyped grammar"));
+      tag_seen = true;

     }
 
   if (*cp == '$')
     {
       if (!type_name)
        type_name = symbol_list_n_type_name_get (rule, dollar_loc, 0);
     }
 
   if (*cp == '$')
     {
       if (!type_name)
        type_name = symbol_list_n_type_name_get (rule, dollar_loc, 0);

-      if (!type_name && typed)
-       complain_at (dollar_loc, _("$$ of `%s' has no declared type"),
-                    rule->sym->tag);
+

       if (!type_name)
       if (!type_name)

-       type_name = "";
+       {
+         if (union_seen | tag_seen)
+           {
+             if (rule->midrule_parent_rule)
+               complain_at (dollar_loc,
+                            _("$$ for the midrule at $%d of `%s'"
+                              " has no declared type"),
+                            rule->midrule_parent_rhs_index,
+                            effective_rule->content.sym->tag);
+             else
+               complain_at (dollar_loc, _("$$ of `%s' has no declared type"),
+                            rule->content.sym->tag);
+           }
+         else
+           untyped_var_seen = true;
+         type_name = "";
+       }
+

       obstack_fgrow1 (&obstack_for_string,
                      "]b4_lhs_value([%s])[", type_name);
       obstack_fgrow1 (&obstack_for_string,
                      "]b4_lhs_value([%s])[", type_name);

-      rule->used = true;
+      rule->action_props.is_value_used = true;

     }
   else
     {
     }
   else
     {

-      long int num;
-      set_errno (0);
-      num = strtol (cp, 0, 10);
-      if (INT_MIN <= num && num <= rule_length && ! get_errno ())
+      long int num = strtol (cp, NULL, 10);
+
+      if (1 - INT_MAX + effective_rule_length <= num
+         && num <= effective_rule_length)

        {
          int n = num;
        {
          int n = num;

-         if (1-n > max_left_semantic_context)
-           max_left_semantic_context = 1-n;
-         if (!type_name && n > 0)
+         if (max_left_semantic_context < 1 - n)
+           max_left_semantic_context = 1 - n;
+         if (!type_name && 0 < n)

            type_name =
            type_name =

-             symbol_list_n_type_name_get (rule, dollar_loc, n);
-         if (!type_name && typed)
-           complain_at (dollar_loc, _("$%d of `%s' has no declared type"),
-                        n, rule->sym->tag);
+             symbol_list_n_type_name_get (effective_rule, dollar_loc, n);

          if (!type_name)
          if (!type_name)

-           type_name = "";
+           {
+             if (union_seen | tag_seen)
+               complain_at (dollar_loc, _("$%d of `%s' has no declared type"),
+                            n, effective_rule->content.sym->tag);
+             else
+               untyped_var_seen = true;
+             type_name = "";
+           }
+

          obstack_fgrow3 (&obstack_for_string,
                          "]b4_rhs_value(%d, %d, [%s])[",
          obstack_fgrow3 (&obstack_for_string,
                          "]b4_rhs_value(%d, %d, [%s])[",

-                         rule_length, n, type_name);
-         symbol_list_n_used_set (rule, n, true);
+                         effective_rule_length, n, type_name);
+          if (n > 0)
+            symbol_list_n_get (effective_rule, n)->action_props.is_value_used =
+              true;

        }
       else
        complain_at (dollar_loc, _("integer out of range: %s"), quote (text));
        }
       else
        complain_at (dollar_loc, _("integer out of range: %s"), quote (text));


@@ -303,22 +351,25 @@ static void
 handle_action_at (symbol_list *rule, char *text, location at_loc)
 {
   char *cp = text + 1;
 handle_action_at (symbol_list *rule, char *text, location at_loc)
 {
   char *cp = text + 1;

-  int rule_length = symbol_list_length (rule->next);
+  int effective_rule_length =
+    (rule->midrule_parent_rule
+     ? rule->midrule_parent_rhs_index - 1
+     : symbol_list_length (rule->next));
+

   locations_flag = true;
 
   if (*cp == '$')
     obstack_sgrow (&obstack_for_string, "]b4_lhs_location[");
   else
     {
   locations_flag = true;
 
   if (*cp == '$')
     obstack_sgrow (&obstack_for_string, "]b4_lhs_location[");
   else
     {

-      long int num;
-      set_errno (0);
-      num = strtol (cp, 0, 10);
+      long int num = strtol (cp, NULL, 10);

 
 

-      if (INT_MIN <= num && num <= rule_length && ! get_errno ())
+      if (1 - INT_MAX + effective_rule_length <= num
+         && num <= effective_rule_length)

        {
          int n = num;
          obstack_fgrow2 (&obstack_for_string, "]b4_rhs_location(%d, %d)[",
        {
          int n = num;
          obstack_fgrow2 (&obstack_for_string, "]b4_rhs_location(%d, %d)[",

-                         rule_length, n);
+                         effective_rule_length, n);

        }
       else
        complain_at (at_loc, _("integer out of range: %s"), quote (text));
        }
       else
        complain_at (at_loc, _("integer out of range: %s"), quote (text));


@@ -330,58 +381,102 @@ handle_action_at (symbol_list *rule, char *text, location at_loc)
 | Initialize the scanner.  |
 `-------------------------*/
 
 | Initialize the scanner.  |
 `-------------------------*/
 

-/* Translate the dollars and ats in \a a, whose location is l.
-   Depending on the \a sc_context (SC_RULE_ACTION, SC_SYMBOL_ACTION,
-   INITIAL), the processing is different.  */
+/* Translate the dollars and ats in \a self, in the context \a sc_context
+   (SC_RULE_ACTION, SC_SYMBOL_ACTION, INITIAL).  */

 
 

-static const char *
-translate_action (int sc_context, symbol_list *rule, const char *a, location l)
+static char const *
+translate_action (code_props *self, int sc_context)

 {
 {

-  const char *res;
+  char *res;

   static bool initialized = false;
   if (!initialized)
     {
       obstack_init (&obstack_for_string);
   static bool initialized = false;
   if (!initialized)
     {
       obstack_init (&obstack_for_string);

-      /* The initial buffer, never used. */
-      yy_delete_buffer (YY_CURRENT_BUFFER);

       yy_flex_debug = 0;
       initialized = true;
     }
 
       yy_flex_debug = 0;
       initialized = true;
     }
 

-  loc->start = loc->end = l.start;
-  yy_switch_to_buffer (yy_scan_string (a));
-  res = code_lex (sc_context, rule);
+  loc->start = loc->end = self->location.start;
+  yy_switch_to_buffer (yy_scan_string (self->code));
+  res = code_lex (self, sc_context);

   yy_delete_buffer (YY_CURRENT_BUFFER);
 
   return res;
 }
 
   yy_delete_buffer (YY_CURRENT_BUFFER);
 
   return res;
 }
 

-const char *
-translate_rule_action (symbol_list *rule, const char *a, location l)
+/*------------------------------------------------------------------------.
+| Implementation of the public interface as documented in "scan-code.h".  |
+`------------------------------------------------------------------------*/
+
+void
+code_props_none_init (code_props *self)

 {
 {

-  return translate_action (SC_RULE_ACTION, rule, a, l);
+  *self = code_props_none;

 }
 
 }
 

-const char *
-translate_symbol_action (const char *a, location l)
+code_props const code_props_none = CODE_PROPS_NONE_INIT;
+
+void
+code_props_plain_init (code_props *self, char const *code, location code_loc)

 {
 {

-  return translate_action (SC_SYMBOL_ACTION, NULL, a, l);
+  self->kind = CODE_PROPS_PLAIN;
+  self->code = code;
+  self->location = code_loc;
+  self->is_value_used = false;
+  self->rule = NULL;

 }
 
 }
 

-const char *
-translate_code (const char *a, location l)
+void
+code_props_symbol_action_init (code_props *self, char const *code,
+                               location code_loc)

 {
 {

-  return translate_action (INITIAL, NULL, a, l);
+  self->kind = CODE_PROPS_SYMBOL_ACTION;
+  self->code = code;
+  self->location = code_loc;
+  self->is_value_used = false;
+  self->rule = NULL;

 }
 
 }
 

-/*-----------------------------------------------.
-| Free all the memory allocated to the scanner.  |
-`-----------------------------------------------*/
+void
+code_props_rule_action_init (code_props *self, char const *code,
+                             location code_loc, symbol_list *rule)
+{
+  self->kind = CODE_PROPS_RULE_ACTION;
+  self->code = code;
+  self->location = code_loc;
+  self->is_value_used = false;
+  self->rule = rule;
+}
+
+void
+code_props_translate_code (code_props *self)
+{
+  switch (self->kind)
+    {
+      case CODE_PROPS_NONE:
+        break;
+      case CODE_PROPS_PLAIN:
+        self->code = translate_action (self, INITIAL);
+        break;
+      case CODE_PROPS_SYMBOL_ACTION:
+        self->code = translate_action (self, SC_SYMBOL_ACTION);
+        break;
+      case CODE_PROPS_RULE_ACTION:
+        self->code = translate_action (self, SC_RULE_ACTION);
+        break;
+    }
+}
+
+void
+code_scanner_last_string_free (void)
+{
+  STRING_FREE;
+}

 
 void
 code_scanner_free (void)
 {
   obstack_free (&obstack_for_string, 0);
   /* Reclaim Flex's buffers.  */
 
 void
 code_scanner_free (void)
 {
   obstack_free (&obstack_for_string, 0);
   /* Reclaim Flex's buffers.  */

-  yy_delete_buffer (YY_CURRENT_BUFFER);
+  yylex_destroy ();

 }
 }