remove useless variable.

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

diff --git a/src/scan-code.l b/src/scan-code.l
index 630d45d5315678b951b57b218809e4f0ebbb2984..88f899021b6315065e137efd60dfa417f52e8c22 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, 2007 Free Software Foundation, Inc.
+   Copyright (C) 2006, 2007, 2008, 2009 Free Software Foundation, Inc.

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


@@ -27,16 +27,16 @@
 #define code_wrap() 1
 
 #define FLEX_PREFIX(Id) code_ ## Id
 #define code_wrap() 1
 
 #define FLEX_PREFIX(Id) code_ ## Id

-#include "flex-scanner.h"
+#include <src/flex-scanner.h>

 
 

-#include "complain.h"
-#include "reader.h"
-#include "getargs.h"
+#include <src/complain.h>
+#include <src/reader.h>
+#include <src/getargs.h>

 #include <get-errno.h>
 #include <quote.h>
 #include <get-errno.h>
 #include <quote.h>

-
-#include "scan-code.h"
-#include "symlist.h"
+#include <src/muscle-tab.h>
+#include <src/scan-code.h>
+#include <src/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. */


@@ -81,6 +81,19 @@ splice        (\\[ \f\t\v]*\n)*
   /* Nesting level of the current code in braces.  */
   int braces_level = 0;
 
   /* 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 direcive, but don't bother.  */
+  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. */


@@ -135,10 +148,12 @@ splice     (\\[ \f\t\v]*\n)*
   "'" {
     STRING_GROW;
     BEGIN SC_CHARACTER;
   "'" {
     STRING_GROW;
     BEGIN SC_CHARACTER;

+    need_semicolon = true;

   }
   "\"" {
     STRING_GROW;
     BEGIN SC_STRING;
   }
   "\"" {
     STRING_GROW;
     BEGIN SC_STRING;

+    need_semicolon = true;

   }
   "/"{splice}"*" {
     STRING_GROW;
   }
   "/"{splice}"*" {
     STRING_GROW;


@@ -154,43 +169,63 @@ splice     (\\[ \f\t\v]*\n)*
 {
   "$"("<"{tag}">")?(-?[0-9]+|"$")  {
     handle_action_dollar (self->rule, yytext, *loc);
 {
   "$"("<"{tag}">")?(-?[0-9]+|"$")  {
     handle_action_dollar (self->rule, yytext, *loc);

+    need_semicolon = true;

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

+    need_semicolon = true;

   }
 
   "$"  {
     warn_at (*loc, _("stray `$'"));
     obstack_sgrow (&obstack_for_string, "$][");
   }
 
   "$"  {
     warn_at (*loc, _("stray `$'"));
     obstack_sgrow (&obstack_for_string, "$][");

+    need_semicolon = true;

   }
   "@"  {
     warn_at (*loc, _("stray `@'"));
     obstack_sgrow (&obstack_for_string, "@@");
   }
   "@"  {
     warn_at (*loc, _("stray `@'"));
     obstack_sgrow (&obstack_for_string, "@@");

+    need_semicolon = true;
+  }
+  "["  {
+    obstack_sgrow (&obstack_for_string, "@{");
+    need_semicolon = true;
+  }
+  "]"  {
+    obstack_sgrow (&obstack_for_string, "@}");
+    need_semicolon = true;

   }
 
   }
 

-  "{"  STRING_GROW; ++braces_level;
+  ";"  STRING_GROW;                 need_semicolon = false;
+  "{"  STRING_GROW; ++braces_level; need_semicolon = false;

   "}"  {
   "}"  {

-    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
        `;'.  But do not append `;' if emulating Yacc, since Yacc does
 
     /* 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.
-
-       FIXME: Bison should warn if a semicolon seems to be necessary
-       here, and should omit the semicolon if it seems unnecessary
-       (e.g., after ';', '{', or '}', each followed by comments or
-       white space).  Such a warning shouldn't depend on --yacc; it
-       should depend on a new --pedantic option, which would cause
-       Bison to warn if it detects an extension to POSIX.  --pedantic
-       should also diagnose other Bison extensions like %yacc.
-       Perhaps there should also be a GCC-style --pedantic-errors
-       option, so that such warnings are diagnosed as errors.  */
-    if (outer_brace && ! yacc_flag)
-      obstack_1grow (&obstack_for_string, ';');
+       not append one.  */
+    if (outer_brace && !yacc_flag && language_prio == default_prio
+        && skeleton_prio == default_prio && need_semicolon && ! in_cpp)
+      {
+       warn_at (*loc, _("a `;' might be needed at the end of action code"));
+       warn_at (*loc, _("future versions of Bison will not add the `;'"));
+       obstack_1grow (&obstack_for_string, ';');
+      }

 
     STRING_GROW;
 
     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>


@@ -201,7 +236,7 @@ splice       (\\[ \f\t\v]*\n)*
   }
   "@$" {
     obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");
   }
   "@$" {
     obstack_sgrow (&obstack_for_string, "]b4_at_dollar[");

-    locations_flag = true;
+    muscle_percent_define_ensure("locations", the_location, true);

   }
 }
 
   }
 }
 


@@ -356,7 +391,7 @@ handle_action_at (symbol_list *rule, char *text, location at_loc)
      ? rule->midrule_parent_rhs_index - 1
      : symbol_list_length (rule->next));
 
      ? rule->midrule_parent_rhs_index - 1
      : symbol_list_length (rule->next));
 

-  locations_flag = true;
+  muscle_percent_define_ensure("locations", at_loc, true);

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