bison: avoid warnings from static code analysis

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

diff --git a/src/scan-code.l b/src/scan-code.l
index 96cab6d150a002df9e3f2c3fc40713d74ebfd6a0..308d1d0dfcf6e2fa0b351723c374841ae068b5bd 100644 (file)
--- a/src/scan-code.l
+++ b/src/scan-code.l
@@ -1,6 +1,6 @@
 /* Bison Action Scanner                             -*- C -*-
 
 /* Bison Action Scanner                             -*- C -*-
 

-   Copyright (C) 2006-2012 Free Software Foundation, Inc.
+   Copyright (C) 2006-2015 Free Software Foundation, Inc.

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


@@ -78,8 +78,9 @@ static bool untyped_var_seen;
 
 /* POSIX says that a tag must be both an id and a C union member, but
    historically almost any character is allowed in a tag.  We disallow
 
 /* POSIX says that a tag must be both an id and a C union member, but
    historically almost any character is allowed in a tag.  We disallow

-   NUL and newline, as this simplifies our implementation.  */
-tag      [^\0\n>]+
+   NUL and newline, as this simplifies our implementation.  We allow
+   "->" as a means to dereference a pointer.  */
+tag      ([^\0\n>]|->)+

 
 /* Zero or more instances of backslash-newline.  Following GCC, allow
    white space between the backslash and the newline.  */
 
 /* Zero or more instances of backslash-newline.  Following GCC, allow
    white space between the backslash and the newline.  */


@@ -95,26 +96,6 @@ ref      -?[0-9]+|{id}|"["{id}"]"|"$"
 %%
 
 %{
 %%
 
 %{

-  /* Nesting level of the current code in braces.  */
-  int braces_level = 0;
-
-  /* Whether a semicolon is probably needed.
-
-     The heuristic is that a semicolon is not needed after '{', '}',
-     ';', or a C preprocessor directive, and that whitespaces and
-     comments do not affect this flag.  Note that '{' does not need a
-     semicolon because of '{}'.  A semicolon may be needed before a
-     cpp directive, but don't bother.
-
-     While it is maintained in several start-conditions (factoring
-     opportunities), it is meaningful only for SC_RULE_ACTION. */
-  bool need_semicolon = false;
-
-  /* Whether in a C preprocessor directive.  Don't use a start condition
-     for this because, at the end of strings and comments, we still need
-     to know whether we're in a directive.  */
-  bool in_cpp = false;
-

   /* 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. */


@@ -167,32 +148,14 @@ ref      -?[0-9]+|{id}|"["{id}"]"|"$"
 
 <SC_RULE_ACTION,SC_SYMBOL_ACTION>
 {
 
 <SC_RULE_ACTION,SC_SYMBOL_ACTION>
 {

-  "'" {
-    STRING_GROW;
-    BEGIN SC_CHARACTER;
-    need_semicolon = true;
-  }
-  "\"" {
-    STRING_GROW;
-    BEGIN SC_STRING;
-    need_semicolon = true;
-  }
-  "/"{splice}"*" {
-    STRING_GROW;
-    BEGIN SC_COMMENT;
-  }
-  "/"{splice}"/" {
-    STRING_GROW;
-    BEGIN SC_LINE_COMMENT;
-  }
+  "'"              STRING_GROW; BEGIN SC_CHARACTER;
+  "\""             STRING_GROW; BEGIN SC_STRING;
+  "/"{splice}"*"   STRING_GROW; BEGIN SC_COMMENT;
+  "/"{splice}"/"   STRING_GROW; BEGIN SC_LINE_COMMENT;
+

   [$@]  {
   [$@]  {

-    complain_at (*loc, Wother, _("stray '%s'"), yytext);
+    complain (loc, Wother, _("stray '%s'"), yytext);

     obstack_escape (&obstack_for_string, yytext);
     obstack_escape (&obstack_for_string, yytext);

-    need_semicolon = true;
-  }
-  [\[\]]  {
-    obstack_escape (&obstack_for_string, yytext);
-    need_semicolon = true;

   }
 }
 
   }
 }
 


@@ -203,49 +166,13 @@ ref      -?[0-9]+|{id}|"["{id}"]"|"$"
     handle_action_dollar (self->rule, yytext, *loc);
     if (ref_tail_fields)
       obstack_sgrow (&obstack_for_string, ref_tail_fields);
     handle_action_dollar (self->rule, yytext, *loc);
     if (ref_tail_fields)
       obstack_sgrow (&obstack_for_string, ref_tail_fields);

-    need_semicolon = true;

   }
   "@"{ref} {
     ref_tail_fields = NULL;
     handle_action_at (self->rule, yytext, *loc);
     if (ref_tail_fields)
       obstack_sgrow (&obstack_for_string, ref_tail_fields);
   }
   "@"{ref} {
     ref_tail_fields = NULL;
     handle_action_at (self->rule, yytext, *loc);
     if (ref_tail_fields)
       obstack_sgrow (&obstack_for_string, ref_tail_fields);

-    need_semicolon = true;
-  }
-
-  ";"  STRING_GROW;                 need_semicolon = false;
-  "{"  STRING_GROW; ++braces_level; need_semicolon = false;
-  "}"  {
-    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
-       ';'.  But do not append ';' if emulating Yacc, since Yacc does
-       not append one.  */
-    if (outer_brace && !yacc_flag && language_prio == default_prio
-        && skeleton_prio == default_prio && need_semicolon && ! in_cpp)
-      {
-        complain_at (*loc, Wother,
-                     _("a ';' might be needed at the end of action code"));
-        complain_at (*loc, Wother,
-                     _("future versions of Bison will not add the ';'"));
-        obstack_1grow (&obstack_for_string, ';');
-      }
-
-    STRING_GROW;
-    need_semicolon = false;

   }
   }

-
-  /* Preprocessing directives should only be recognized at the beginning
-     of lines, allowing whitespace including comments, but in C/C++,
-     '#' can only be the start of preprocessor directives or within
-     '#define' directives anyway, so don't bother with begin of line.  */
-  "#"       STRING_GROW; in_cpp = true;
-
-  {splice}  STRING_GROW;
-  [\n\r]    STRING_GROW; if (in_cpp) in_cpp = need_semicolon = false;
-  [ \t\f]   STRING_GROW;
-  .         STRING_GROW; need_semicolon = true;

 }
 
 <SC_SYMBOL_ACTION>
 }
 
 <SC_SYMBOL_ACTION>


@@ -400,23 +327,34 @@ get_at_spec(unsigned symbol_index)
 }
 
 static void
 }
 
 static void

-show_sub_message (const char* cp, bool explicit_bracketing,
+show_sub_message (warnings warning,
+                  const char* cp, bool explicit_bracketing,

                   int midrule_rhs_index, char dollar_or_at,
                   int midrule_rhs_index, char dollar_or_at,

-                  warnings wflags, unsigned indent,
-                  const variant *var)
+                  unsigned indent, const variant *var)

 {
   const char *at_spec = get_at_spec (var->symbol_index);
 
   if (var->err == 0)
 {
   const char *at_spec = get_at_spec (var->symbol_index);
 
   if (var->err == 0)

-    complain_at_indent (var->loc, wflags, &indent,
-                        _("refers to: %c%s at %s"), dollar_or_at,
-                        var->id, at_spec);
+    complain_indent (&var->loc, warning, &indent,
+                     _("refers to: %c%s at %s"), dollar_or_at,
+                     var->id, at_spec);

   else
     {
       static struct obstack msg_buf;
       const char *tail = explicit_bracketing ? "" : cp + strlen (var->id);
   else
     {
       static struct obstack msg_buf;
       const char *tail = explicit_bracketing ? "" : cp + strlen (var->id);

-      const char *id = var->hidden_by ? var->hidden_by->id : var->id;
-      location id_loc = var->hidden_by ? var->hidden_by->loc : var->loc;
+      const char *id;
+      location id_loc;
+
+      if (var->hidden_by)
+        {
+          id = var->hidden_by->id;
+          id_loc = var->hidden_by->loc;
+        }
+      else
+        {
+          id = var->id;
+          id_loc = var->loc;
+        }

 
       /* Create the explanation message. */
       obstack_init (&msg_buf);
 
       /* Create the explanation message. */
       obstack_init (&msg_buf);


@@ -445,23 +383,25 @@ show_sub_message (const char* cp, bool explicit_bracketing,
                         _(", cannot be accessed from mid-rule action at $%d"),
                         midrule_rhs_index);
 
                         _(", cannot be accessed from mid-rule action at $%d"),
                         midrule_rhs_index);
 

-      complain_at_indent (id_loc, wflags, &indent, "%s",
-                          obstack_finish0 (&msg_buf));
+      complain_indent (&id_loc, warning, &indent, "%s",
+                        obstack_finish0 (&msg_buf));

       obstack_free (&msg_buf, 0);
     }
 }
 
 static void
       obstack_free (&msg_buf, 0);
     }
 }
 
 static void

-show_sub_messages (const char* cp, bool explicit_bracketing,
+show_sub_messages (warnings warning,
+                   const char* cp, bool explicit_bracketing,

                    int midrule_rhs_index, char dollar_or_at,
                    int midrule_rhs_index, char dollar_or_at,

-                   warnings wflags, unsigned indent)
+                   unsigned indent)

 {
   unsigned i;
 
   for (i = 0; i < variant_count; ++i)
 {
   unsigned i;
 
   for (i = 0; i < variant_count; ++i)

-    show_sub_message (cp, explicit_bracketing,
+    show_sub_message (warning | silent,
+                      cp, explicit_bracketing,

                       midrule_rhs_index, dollar_or_at,
                       midrule_rhs_index, dollar_or_at,

-                      wflags, indent, &variant_table[i]);
+                      indent, &variant_table[i]);

 }
 
 /* Returned from "parse_ref" when the reference
 }
 
 /* Returned from "parse_ref" when the reference


@@ -472,9 +412,6 @@ show_sub_messages (const char* cp, bool explicit_bracketing,
    points to LHS ($$) of the current rule or midrule. */
 #define LHS_REF (INT_MIN + 1)
 
    points to LHS ($$) of the current rule or midrule. */
 #define LHS_REF (INT_MIN + 1)
 

-/* Sub-messages indent. */
-#define SUB_INDENT (4)
-

 /* Parse named or positional reference. In case of positional
    references, can return negative values for $-n "deep" stack
    accesses. */
 /* Parse named or positional reference. In case of positional
    references, can return negative values for $-n "deep" stack
    accesses. */


@@ -500,8 +437,8 @@ parse_ref (char *cp, symbol_list *rule, int rule_length,
         return num;
       else
         {
         return num;
       else
         {

-          complain_at (text_loc, complaint, _("integer out of range: %s"),
-                       quote (text));
+          complain (&text_loc, complaint, _("integer out of range: %s"),
+                    quote (text));

           return INVALID_REF;
         }
     }
           return INVALID_REF;
         }
     }


@@ -589,32 +526,33 @@ parse_ref (char *cp, symbol_list *rule, int rule_length,
           cp_end - cp : ref_tail_fields - cp;
         unsigned indent = 0;
 
           cp_end - cp : ref_tail_fields - cp;
         unsigned indent = 0;
 

-        complain_at_indent (text_loc, complaint, &indent,
-                            _("invalid reference: %s"), quote (text));
+        complain_indent (&text_loc, complaint, &indent,
+                         _("invalid reference: %s"), quote (text));

         indent += SUB_INDENT;
         if (len == 0)
           {
             location sym_loc = text_loc;
             sym_loc.start.column += 1;
             sym_loc.end = sym_loc.start;
         indent += SUB_INDENT;
         if (len == 0)
           {
             location sym_loc = text_loc;
             sym_loc.start.column += 1;
             sym_loc.end = sym_loc.start;

-            complain_at_indent (sym_loc, complaint, &indent,
-                                _("syntax error after '%c', expecting integer, "
-                                  "letter, '_', '[', or '$'"),
-                                dollar_or_at);
+            complain_indent (&sym_loc, complaint, &indent,
+                             _("syntax error after '%c', expecting integer, "
+                               "letter, '_', '[', or '$'"),
+                             dollar_or_at);

           }
         else if (midrule_rhs_index)
           }
         else if (midrule_rhs_index)

-          complain_at_indent (rule->location, complaint, &indent,
-                              _("symbol not found in production before $%d: "
-                                "%.*s"),
-                              midrule_rhs_index, len, cp);
+          complain_indent (&rule->location, complaint, &indent,
+                           _("symbol not found in production before $%d: "
+                             "%.*s"),
+                           midrule_rhs_index, len, cp);

         else
         else

-          complain_at_indent (rule->location, complaint, &indent,
-                              _("symbol not found in production: %.*s"),
-                              len, cp);
+          complain_indent (&rule->location, complaint, &indent,
+                           _("symbol not found in production: %.*s"),
+                           len, cp);

 
         if (variant_count > 0)
 
         if (variant_count > 0)

-          show_sub_messages (cp, explicit_bracketing, midrule_rhs_index,
-                             dollar_or_at, complaint, indent);
+          show_sub_messages (complaint,
+                             cp, explicit_bracketing, midrule_rhs_index,
+                             dollar_or_at, indent);

         return INVALID_REF;
       }
     case 1:
         return INVALID_REF;
       }
     case 1:


@@ -622,10 +560,11 @@ parse_ref (char *cp, symbol_list *rule, int rule_length,
         unsigned indent = 0;
         if (variant_count > 1)
           {
         unsigned indent = 0;
         if (variant_count > 1)
           {

-            complain_at_indent (text_loc, Wother, &indent,
-                                _("misleading reference: %s"), quote (text));
-            show_sub_messages (cp, explicit_bracketing, midrule_rhs_index,
-                               dollar_or_at, Wother, indent + SUB_INDENT);
+            complain_indent (&text_loc, Wother, &indent,
+                             _("misleading reference: %s"), quote (text));
+            show_sub_messages (Wother,
+                               cp, explicit_bracketing, midrule_rhs_index,
+                               dollar_or_at, indent + SUB_INDENT);

           }
         {
           unsigned symbol_index =
           }
         {
           unsigned symbol_index =


@@ -637,16 +576,14 @@ parse_ref (char *cp, symbol_list *rule, int rule_length,
     default:
       {
         unsigned indent = 0;
     default:
       {
         unsigned indent = 0;

-        complain_at_indent (text_loc, complaint, &indent,
-                            _("ambiguous reference: %s"), quote (text));
-        show_sub_messages (cp, explicit_bracketing, midrule_rhs_index,
-                           dollar_or_at, complaint, indent + SUB_INDENT);
+        complain_indent (&text_loc, complaint, &indent,
+                         _("ambiguous reference: %s"), quote (text));
+        show_sub_messages (complaint,
+                           cp, explicit_bracketing, midrule_rhs_index,
+                           dollar_or_at, indent + SUB_INDENT);

         return INVALID_REF;
       }
     }
         return INVALID_REF;
       }
     }

-
-  /* Not reachable. */
-  return INVALID_REF;

 }
 
 /* Keeps track of the maximum number of semantic values to the left of
 }
 
 /* Keeps track of the maximum number of semantic values to the left of


@@ -667,15 +604,16 @@ fetch_type_name (char *cp, char const **type_name,
   if (*cp == '<')
     {
       *type_name = ++cp;
   if (*cp == '<')
     {
       *type_name = ++cp;

-      while (*cp != '>')
+      /* Series of non-'>' or "->".  */
+      while (*cp != '>' || cp[-1] == '-')

         ++cp;
 
       /* The '>' symbol will be later replaced by '\0'. Original
          'text' is needed for error messages. */
       ++cp;
       if (untyped_var_seen)
         ++cp;
 
       /* The '>' symbol will be later replaced by '\0'. Original
          'text' is needed for error messages. */
       ++cp;
       if (untyped_var_seen)

-        complain_at (dollar_loc, complaint,
-                     _("explicit type given in untyped grammar"));
+        complain (&dollar_loc, complaint,
+                  _("explicit type given in untyped grammar"));

       tag_seen = true;
     }
   return cp;
       tag_seen = true;
     }
   return cp;


@@ -733,15 +671,15 @@ handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)
           if (union_seen | tag_seen)
             {
               if (rule->midrule_parent_rule)
           if (union_seen | tag_seen)
             {
               if (rule->midrule_parent_rule)

-                complain_at (dollar_loc, complaint,
+                complain (&dollar_loc, complaint,

                              _("$$ for the midrule at $%d of %s"
                                " has no declared type"),
                              rule->midrule_parent_rhs_index,
                              quote (effective_rule->content.sym->tag));
               else
                              _("$$ for the midrule at $%d of %s"
                                " has no declared type"),
                              rule->midrule_parent_rhs_index,
                              quote (effective_rule->content.sym->tag));
               else

-                complain_at (dollar_loc, complaint,
-                             _("$$ of %s has no declared type"),
-                             quote (rule->content.sym->tag));
+                complain (&dollar_loc, complaint,
+                          _("$$ of %s has no declared type"),
+                          quote (rule->content.sym->tag));

             }
           else
             untyped_var_seen = true;
             }
           else
             untyped_var_seen = true;


@@ -762,9 +700,9 @@ handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)
       if (!type_name)
         {
           if (union_seen | tag_seen)
       if (!type_name)
         {
           if (union_seen | tag_seen)

-            complain_at (dollar_loc, complaint,
-                         _("$%s of %s has no declared type"), cp,
-                         quote (effective_rule->content.sym->tag));
+            complain (&dollar_loc, complaint,
+                      _("$%s of %s has no declared type"), cp,
+                      quote (effective_rule->content.sym->tag));

           else
             untyped_var_seen = true;
         }
           else
             untyped_var_seen = true;
         }


@@ -773,7 +711,7 @@ handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)
                       "]b4_rhs_value(%d, %d, ", effective_rule_length, n);
       obstack_quote (&obstack_for_string, type_name);
       obstack_sgrow (&obstack_for_string, ")[");
                       "]b4_rhs_value(%d, %d, ", effective_rule_length, n);
       obstack_quote (&obstack_for_string, type_name);
       obstack_sgrow (&obstack_for_string, ")[");

-      if (n > 0)
+      if (0 < n)

         symbol_list_n_get (effective_rule, n)->action_props.is_value_used =
           true;
       break;
         symbol_list_n_get (effective_rule, n)->action_props.is_value_used =
           true;
       break;