Added Yacc library to Bison

[Paul Eggert]

POSIX requires that there be a Yacc library, linkable by "cc -ly".  I
installed the following patch to Bison so that Bison can conform to
this POSIX requirement.

2002-11-30  Paul Eggert  <address@hidden>

        Add Yacc library, since POSIX requires it.
        * doc/bison.texinfo (Yacc Library): New node.  Regenerate top menu.
        * lib/Makefile.am (lib_LIBRARIES, liby_a_SOURCES): New macros.
        * lib/main.c, lib/yyerror.c: New files.

Index: doc/bison.texinfo
===================================================================
RCS file: /cvsroot/bison/bison/doc/bison.texinfo,v
retrieving revision 1.88
diff -p -u -r1.88 bison.texinfo
--- doc/bison.texinfo   30 Nov 2002 07:42:37 -0000      1.88
+++ doc/bison.texinfo   30 Nov 2002 09:07:52 -0000
@@ -119,7 +119,8 @@ Reference sections:
 * Copying This Manual::  License for copying this manual.
 * Index::             Cross-references to the text.
 
address@hidden --- The Detailed Node Listing ---
address@hidden
+ --- The Detailed Node Listing ---
 
 The Concepts of Bison
 
@@ -130,6 +131,8 @@ The Concepts of Bison
                         a semantic value (the value of an integer,
                         the name of an identifier, etc.).
 * Semantic Actions::  Each rule can have an action containing C code.
+* GLR Parsers::       Writing parsers for general context-free languages
+* Locations Overview::    Tracking Locations.
 * Bison Parser::      What are Bison's input and output,
                         how is the output used?
 * Stages::            Stages in writing and running Bison grammars.
@@ -143,8 +146,8 @@ Examples
                         Operator precedence is introduced.
 * Simple Error Recovery::  Continuing after syntax errors.
 * Location Tracking Calc:: Demonstrating the use of @@@var{n} and @@$.
-* Multi-function Calc::    Calculator with memory and trig functions.
-                        It uses multiple data-types for semantic values.
+* Multi-function Calc::  Calculator with memory and trig functions.
+                           It uses multiple data-types for semantic values.
 * Exercises::         Ideas for improving the multi-function calculator.
 
 Reverse Polish Notation Calculator
@@ -182,15 +185,16 @@ Bison Grammar Files
 * Rules::             How to write grammar rules.
 * Recursion::         Writing recursive rules.
 * Semantics::         Semantic values and actions.
+* Locations::         Locations and actions.
 * Declarations::      All kinds of Bison declarations are described here.
 * Multiple Parsers::  Putting more than one Bison parser in one program.
 
 Outline of a Bison Grammar
 
-* Prologue::          Syntax and usage of the prologue (declarations section).
+* Prologue::          Syntax and usage of the prologue.
 * Bison Declarations::  Syntax and usage of the Bison declarations section.
 * Grammar Rules::     Syntax and usage of the grammar rules section.
-* Epilogue::          Syntax and usage of the epilogue (additional code 
section).
+* Epilogue::          Syntax and usage of the epilogue.
 
 Defining Language Semantics
 
@@ -202,6 +206,12 @@ Defining Language Semantics
                       This says when, why and how to use the exceptional
                         action in the middle of a rule.
 
+Tracking Locations
+
+* Location Type::               Specifying a data type for locations.
+* Actions and Locations::       Using locations in actions.
+* Location Default Action::     Defining a general way to compute locations.
+
 Bison Declarations
 
 * Token Decl::        Declaring terminal symbols.
@@ -229,7 +239,7 @@ The Lexical Analyzer Function @code{yyle
                         of the token it has read.
 * Token Positions::   How @code{yylex} must return the text position
                         (line number, etc.) of the token, if the
-                         actions want that.
+                        actions want that.
 * Pure Calling::      How the calling convention differs
                         in a pure parser (@pxref{Pure Decl, ,A Pure 
(Reentrant) Parser}).
 
@@ -259,7 +269,7 @@ Handling Context Dependencies
 * Tie-in Recovery::   Lexical tie-ins have implications for how
                         error recovery rules must be written.
 
-Understanding or Debugging Your Parser
+Debugging Your Parser
 
 * Understanding::     Understanding the structure of your parser.
 * Tracing::           Tracing the execution of your parser.
@@ -269,6 +279,7 @@ Invoking Bison
 * Bison Options::     All the options described in detail,
                         in alphabetical order by short options.
 * Option Cross Key::  Alphabetical list of long options.
+* Yacc Library::      Yacc-compatible @code{yylex} and @code{main}.
 
 Frequently Asked Questions
 
@@ -6075,6 +6086,7 @@ will produce @file{output.c++} and @file
 * Bison Options::     All the options described in detail,
                         in alphabetical order by short options.
 * Option Cross Key::  Alphabetical list of long options.
+* Yacc Library::      Yacc-compatible @code{yylex} and @code{main}.
 @end menu
 
 @node Bison Options
@@ -6265,6 +6277,32 @@ the corresponding short option.
 --yacc                                -y
 @end example
 @end ifinfo
+
address@hidden Yacc Library
address@hidden Yacc Library
+
+The Yacc library contains default implementations of the
address@hidden and @code{main} functions.  These default
+implementations are normally not useful, but @acronym{POSIX} requires
+them.  To use the Yacc library, link your program with the
address@hidden option.  Note that Bison's implementation of the Yacc
+library is distributed under the terms of the @acronym{GNU} General
+Public License (@pxref{Copying}).
+
+If you use the Yacc library's @code{yyerror} function, you should
+declare @code{yyerror} as follows:
+
address@hidden
+int yyerror (char const *);
address@hidden example
+
+Bison ignores the @code{int} value returned by this @code{yyerror}.
+If you use the Yacc library's @code{main} function, your
address@hidden function should have the following type signature:
+
address@hidden
+int yyparse (void);
address@hidden example
 
 @c ================================================= Invoking Bison
 
Index: lib/Makefile.am
===================================================================
RCS file: /cvsroot/bison/bison/lib/Makefile.am,v
retrieving revision 1.34
diff -p -u -r1.34 Makefile.am
--- lib/Makefile.am     3 Nov 2002 08:39:43 -0000       1.34
+++ lib/Makefile.am     30 Nov 2002 09:07:52 -0000
@@ -17,12 +17,15 @@
 
 AM_CFLAGS = $(WARNING_CFLAGS)
 
+lib_LIBRARIES = liby.a
 noinst_LIBRARIES = libbison.a
 
 # config.h is in build/., and system.h is in src/src/.
 INCLUDES = -I$(top_builddir)      \
            -I$(top_srcdir)/src \
            -I$(top_srcdir)/lib
+
+liby_a_SOURCES = main.c yyerror.c
 
 # Heck, we are still using an old version of Automake which does not
 # understand inner AC_LIBOBJ (i.e., from Autoconf itself, not from
--- /dev/null   2002-11-30 01:07:34.000000000 -0800
+++ lib/main.c  2002-11-29 23:05:04.879290000 -0800
@@ -0,0 +1,38 @@
+/* Yacc library main function.
+
+   Copyright (C) 2002 Free Software Foundation, Inc.
+
+   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.
+
+   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.
+
+   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., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <config.h>
+
+#if HAVE_LOCALE_H
+# include <locale.h>
+#endif
+#if ! HAVE_SETLOCALE
+# define setlocale(Category, Locale)
+#endif
+
+int yyparse (void);
+
+int
+main (void)
+{
+  setlocale (LC_ALL, "");
+  return yyparse ();
+}
--- /dev/null   2002-11-30 01:07:34.000000000 -0800
+++ lib/yyerror.c       2002-11-29 23:05:47.677281000 -0800
@@ -0,0 +1,30 @@
+/* Yacc library error-printing function.
+
+   Copyright (C) 2002 Free Software Foundation, Inc.
+
+   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.
+
+   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.
+
+   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., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <stdio.h>
+
+int yyerror (char const *);
+
+int
+yyerror (char const *message)
+{
+  return fprintf (stderr, "%s\n", message);
+}