doc: one of the fixes for an ambiguous grammar was ambiguous too

[bison.git] / src / system.h

diff --git a/src/system.h b/src/system.h
index e297f608cacdde8aa4401339e94a6c2599f16128..bf7f59f9dbb66ab718f148e81517aacf7efbd50b 100644 (file)
--- a/src/system.h
+++ b/src/system.h
@@ -1,10 +1,11 @@
-/* system-dependent definitions for Bison.
-   Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.
+/* System-dependent definitions for Bison.

 
 

-   This program is free software; you can redistribute it and/or modify
+   Copyright (C) 2000-2007, 2009-2012 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
    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.
+   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,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
 
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of


@@ -12,188 +13,137 @@
    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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

 
 #ifndef BISON_SYSTEM_H
 
 #ifndef BISON_SYSTEM_H

-#define BISON_SYSTEM_H
-
-#if HAVE_CONFIG_H
-# include <config.h>
-#endif
-
-/* AIX requires this to be the first thing in the file.  */
-#ifdef __GNUC__
-# define alloca(Size) __builtin_alloca (Size)
-#else
-# if HAVE_ALLOCA_H
-#  include <alloca.h>
-# else
-#  ifdef _AIX
- #pragma alloca
-#  else
-#   ifndef alloca /* predefined by HP cc +Olibcalls */
-char *alloca ();
-#   endif
-#  endif
+# define BISON_SYSTEM_H
+
+/* flex 2.5.31 gratutiously defines macros like INT8_MIN.  But this
+   runs afoul of pre-C99 compilers that have <inttypes.h> or
+   <stdint.h>, which are included below if available.  It also runs
+   afoul of pre-C99 compilers that define these macros in <limits.h>.  */
+# if ! defined __STDC_VERSION__ || __STDC_VERSION__ < 199901
+#  undef INT8_MIN
+#  undef INT16_MIN
+#  undef INT32_MIN
+#  undef INT8_MAX
+#  undef INT16_MAX
+#  undef UINT8_MAX
+#  undef INT32_MAX
+#  undef UINT16_MAX
+#  undef UINT32_MAX

 # endif
 # endif

-#endif
-
-#include <stdio.h>

 
 

-#include <assert.h>
-
-#if HAVE_SYS_TYPES_H
-# include <sys/types.h>
-#endif
-
-#if HAVE_STDLIB_H
+# include <limits.h>
+# include <stddef.h>

 # include <stdlib.h>
 # include <stdlib.h>

-#endif
-
-/* The following test is to work around the gross typo in
-   systems like Sony NEWS-OS Release 4.0C, whereby EXIT_FAILURE
-   is defined to 0, not 1.  */
-#if !EXIT_FAILURE
-# undef EXIT_FAILURE
-# define EXIT_FAILURE 1
-#endif
-
-#ifndef EXIT_SUCCESS
-# define EXIT_SUCCESS 0
-#endif
-
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
-
-#if defined(STDC_HEADERS) || defined(HAVE_STRING_H)

 # include <string.h>
 # include <string.h>

-/* An ANSI string.h and pre-ANSI memory.h might conflict.  */
-# if !defined(STDC_HEADERS) && defined(HAVE_MEMORY_H)
-#  include <memory.h>
-# endif /* not STDC_HEADERS and HAVE_MEMORY_H */
-#else /* not STDC_HEADERS and not HAVE_STRING_H */
-# include <strings.h>
-/* memory.h and strings.h conflict on some systems.  */
-#endif /* not STDC_HEADERS and not HAVE_STRING_H */
-
-#include <errno.h>
-#include <limits.h>
-
-# include "xalloc.h"
-
-/* From xstrndup.c.  */
-char *xstrndup (const char *s, size_t n);
-
-
-/*----------------.
-| Using timevar.  |
-`----------------*/
-
-#include "timevar.h"
-extern int time_report;
-
-
-/*---------------------.
-| Missing prototypes.  |
-`---------------------*/
-
-#if defined HAVE_DECL_STPCPY && !HAVE_DECL_STPCPY
-char *stpcpy (char *dest, const char *src);
-#endif
-
-#if defined HAVE_DECL_STRCHR && !HAVE_DECL_STRCHR
-char *strchr (const char *s, int c);
-#endif
-
-#if defined HAVE_DECL_STRSPN && !HAVE_DECL_STRSPN
-size_t strspn (const char *s, const char *accept);
-#endif
+# include <unistd.h>
+# include <inttypes.h>

 
 

-#if defined HAVE_DECL_STRNLEN && !HAVE_DECL_STRNLEN
-size_t strnlen (const char *s, size_t maxlen);
-#endif
+# ifndef UINTPTR_MAX
+/* This isn't perfect, but it's good enough for Bison, which needs
+   only to hash pointers.  */
+typedef size_t uintptr_t;
+# endif

 
 

-#if defined HAVE_DECL_MEMCHR && !HAVE_DECL_MEMCHR
-void *memchr (const void *s, int c, size_t n);
-#endif
+// Version mismatch.
+# define EX_MISMATCH 63

 
 

-#if defined HAVE_DECL_MEMRCHR && !HAVE_DECL_MEMRCHR
-void *memrchr (const void *s, int c, size_t n);
-#endif
+/*---------.
+| Gnulib.  |
+`---------*/

 
 

+# include <unlocked-io.h>
+# include <verify.h>
+# include <xalloc.h>

 
 
 /*-----------------.
 | GCC extensions.  |
 `-----------------*/
 
 
 
 /*-----------------.
 | GCC extensions.  |
 `-----------------*/
 

-/* Use this to suppress gcc's `...may be used before initialized'
-   warnings.  */
-#ifdef lint
-# define IF_LINT(Code) Code
-#else
-# define IF_LINT(Code) /* empty */
-#endif
-
-#ifndef __attribute__
+/* Use PACIFY_CC to indicate that Code is unimportant to the logic of Bison
+   but that it is necessary for suppressing compiler warnings.  For example,
+   Code might be a variable initializer that's always overwritten before the
+   variable is used.
+
+   PACIFY_CC is intended to be useful only as a comment as it does not alter
+   Code.  It is tempting to redefine PACIFY_CC so that it will suppress Code
+   when configuring without --enable-gcc-warnings.  However, that would mean
+   that, for maintainers, Bison would compile with potentially less warnings
+   and safer logic than it would for users.  Due to the overhead of M4,
+   suppressing Code is unlikely to offer any significant improvement in
+   Bison's performance anyway.  */
+# define PACIFY_CC(Code) Code
+
+# ifndef __attribute__

 /* This feature is available in gcc versions 2.5 and later.  */
 /* This feature is available in gcc versions 2.5 and later.  */

-# if !defined (__GNUC__) || __GNUC__ < 2 || \
-(__GNUC__ == 2 && __GNUC_MINOR__ < 5) || __STRICT_ANSI__
-#  define __attribute__(Spec) /* empty */
+#  if (! defined __GNUC__ || __GNUC__ < 2 \
+       || (__GNUC__ == 2 && __GNUC_MINOR__ < 5))
+#   define __attribute__(Spec) /* empty */
+#  endif

 # endif
 # endif

-#endif

 
 /* The __-protected variants of `format' and `printf' attributes
    are accepted by gcc versions 2.6.4 (effectively 2.7) and later.  */
 
 /* The __-protected variants of `format' and `printf' attributes
    are accepted by gcc versions 2.6.4 (effectively 2.7) and later.  */

-#if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 7)
-# define __format__ format
-# define __printf__ printf
-#endif
+# if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 7)
+#  define __format__ format
+#  define __printf__ printf
+# endif
+
+# ifndef ATTRIBUTE_NORETURN
+#  define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__))
+# endif

 
 

-#ifndef ATTRIBUTE_NORETURN
-# define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__))
-#endif
+# ifndef ATTRIBUTE_UNUSED
+#  define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
+# endif

 
 

-#ifndef ATTRIBUTE_UNUSED
-# define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
-#endif

 
 /*------.
 | NLS.  |
 `------*/
 
 
 /*------.
 | NLS.  |
 `------*/
 

-#if HAVE_LOCALE_H

 # include <locale.h>
 # include <locale.h>

-#endif
-#if !HAVE_SETLOCALE
-# define setlocale(Category, Locale)
-#endif
-
-#include "gettext.h"
-#define _(Msgid)  gettext (Msgid)
-#define N_(Msgid) (Msgid)
-

 
 

-/*-------------------------------.
-| Fix broken compilation flags.  |
-`-------------------------------*/
-
-#ifndef LOCALEDIR
-# define LOCALEDIR "/usr/local/share/locale"
-#endif
+# include <gettext.h>
+# define _(Msgid)  gettext (Msgid)
+# define N_(Msgid) (Msgid)

 
 
 /*-----------.
 | Booleans.  |
 `-----------*/
 
 
 
 /*-----------.
 | Booleans.  |
 `-----------*/
 

-#if HAVE_STDBOOL_H

 # include <stdbool.h>
 # include <stdbool.h>

-#else
-typedef enum {false = 0, true = 1} bool;
-#endif
+
+
+
+/*-------------.
+| Assertions.  |
+`-------------*/
+
+/* In the past, Bison defined aver to simply invoke abort in the case of
+   a failed assertion.  The rationale was that <assert.h>'s assertions
+   were too heavyweight and could be disabled too easily.  See
+   discussions at
+   <http://lists.gnu.org/archive/html/bison-patches/2006-01/msg00080.html>
+   <http://lists.gnu.org/archive/html/bison-patches/2006-09/msg00111.html>.
+
+   However, normal assert output can be helpful during development and
+   in bug reports from users.  Moreover, it's not clear now that
+   <assert.h>'s assertions are significantly heavyweight.  Finally, if
+   users want to experiment with disabling assertions, it's debatable
+   whether it's our responsibility to stop them.  See discussion
+   starting at
+   <http://lists.gnu.org/archive/html/bison-patches/2009-09/msg00013.html>.
+
+   For now, we use assert but we call it aver throughout Bison in case
+   we later wish to try another scheme.
+*/
+# include <assert.h>
+# define aver assert

 
 
 /*-----------.
 
 
 /*-----------.


@@ -202,38 +152,52 @@ typedef enum {false = 0, true = 1} bool;
 
 # define obstack_chunk_alloc xmalloc
 # define obstack_chunk_free  free
 
 # define obstack_chunk_alloc xmalloc
 # define obstack_chunk_free  free

-# include "obstack.h"
+# include <obstack.h>

 
 

-#define obstack_sgrow(Obs, Str) \
+# define obstack_sgrow(Obs, Str)                \

   obstack_grow (Obs, Str, strlen (Str))
 
   obstack_grow (Obs, Str, strlen (Str))
 

-#define obstack_fgrow1(Obs, Format, Arg1)      \
-do {                                           \
-  char buf[4096];                              \
-  sprintf (buf, Format, Arg1);                 \
-  obstack_grow (Obs, buf, strlen (buf));       \
-} while (0)
+/* Output Str escaped for our postprocessing (i.e., escape M4 special
+   characters).
+
+   For instance "[foo]" -> "@{foo@}", "$$" -> "$][$][". */
+
+# define obstack_escape(Obs, Str)                       \
+  do {                                                  \
+    char const *p;                                      \
+    for (p = Str; *p; p++)                              \
+      switch (*p)                                       \
+        {                                               \
+        case '$': obstack_sgrow (Obs, "$]["); break;    \
+        case '@': obstack_sgrow (Obs, "@@" ); break;    \
+        case '[': obstack_sgrow (Obs, "@{" ); break;    \
+        case ']': obstack_sgrow (Obs, "@}" ); break;    \
+        default:  obstack_1grow (Obs, *p   ); break;    \
+        }                                               \
+  } while (0)

 
 

-#define obstack_fgrow2(Obs, Format, Arg1, Arg2)        \
-do {                                           \
-  char buf[4096];                              \
-  sprintf (buf, Format, Arg1, Arg2);           \
-  obstack_grow (Obs, buf, strlen (buf));       \
-} while (0)

 
 

-#define obstack_fgrow3(Obs, Format, Arg1, Arg2, Arg3)  \
-do {                                                   \
-  char buf[4096];                                      \
-  sprintf (buf, Format, Arg1, Arg2, Arg3);             \
-  obstack_grow (Obs, buf, strlen (buf));               \
-} while (0)
+/* Output Str both quoted for M4 (i.e., embed in [[...]]), and escaped
+   for our postprocessing (i.e., escape M4 special characters).  If
+   Str is empty (or NULL), output "[]" instead of "[[]]" as it make M4
+   programming easier (m4_ifval can be used).
+
+   For instance "[foo]" -> "[[@{foo@}]]", "$$" -> "[[$][$][]]". */
+
+# define obstack_quote(Obs, Str)                \
+  do {                                          \
+    char const* obstack_quote_p = Str;          \
+    if (obstack_quote_p && obstack_quote_p[0])  \
+      {                                         \
+        obstack_sgrow (Obs, "[[");              \
+        obstack_escape (Obs, obstack_quote_p);  \
+        obstack_sgrow (Obs, "]]");              \
+      }                                         \
+    else                                        \
+      obstack_sgrow (Obs, "[]");                \
+  } while (0)
+

 
 

-#define obstack_fgrow4(Obs, Format, Arg1, Arg2, Arg3, Arg4)    \
-do {                                                           \
-  char buf[4096];                                              \
-  sprintf (buf, Format, Arg1, Arg2, Arg3, Arg4);               \
-  obstack_grow (Obs, buf, strlen (buf));                       \
-} while (0)

 
 
 
 
 
 


@@ -241,25 +205,13 @@ do {                                                              \
 | Extensions to use for the output files.  |
 `-----------------------------------------*/
 
 | Extensions to use for the output files.  |
 `-----------------------------------------*/
 

-#ifdef VMS
-  /* VMS. */
-# define EXT_TAB       "_tab"
-# define EXT_OUTPUT    ".output"
-#else /* ! VMS */
-# ifdef MSDOS
-   /* MS DOS. */
-#  define EXT_TAB      "_tab"
-#  define EXT_OUTPUT   ".out"
-# else /* ! MSDOS */
-  /* Standard. */
-#  define EXT_TAB      ".tab"
-#  define EXT_OUTPUT   ".output"
-# endif /* ! MSDOS */
-#endif /* ! VMS */
+# ifndef OUTPUT_EXT
+#  define OUTPUT_EXT ".output"
+# endif

 
 

-#ifndef DEFAULT_TMPDIR
-# define DEFAULT_TMPDIR "/tmp"
-#endif
+# ifndef TAB_EXT
+#  define TAB_EXT ".tab"
+# endif

 
 
 
 
 
 


@@ -267,15 +219,15 @@ do {                                                              \
 | Free a linked list.  |
 `---------------------*/
 
 | Free a linked list.  |
 `---------------------*/
 

-#define LIST_FREE(Type, List)                  \
-do {                                           \
-  Type *_node, *_next;                         \
-  for (_node = List; _node; _node = _next)     \
-    {                                          \
-      _next = _node->next;                     \
-      XFREE (_node);                           \
-    }                                          \
-} while (0)
+# define LIST_FREE(Type, List)                  \
+  do {                                          \
+    Type *_node, *_next;                        \
+    for (_node = List; _node; _node = _next)    \
+      {                                         \
+        _next = _node->next;                    \
+        free (_node);                           \
+      }                                         \
+  } while (0)

 
 
 /*---------------------------------------------.
 
 
 /*---------------------------------------------.