Treat %error-verbose as %define error_verbose.

This allows to pass -Derror_verbose on the command line.  Better yet, it
allows to pass -Derror_verbose=$(ERROR_VERBOSE), with ERROR_VERBOSE being
defined as false or true.

	* data/bison.m4 (b4_percent_define_if_define): Instead of relying
	on b4_percent_define_ifdef, for does not check the defined value,
	but only whether the symbol is defined, rely on
	b4_percent_define_flag_if, so that a value of "false" is processed
	as a false.
	If not defined, define the flag to "false".
	(b4_error_verbose_if): New.
	* data/glr.c, data/lalr1.cc, data/yacc.c: Use it instead of
	b4_error_verbose_flag.
	* src/getargs.h, src/getargs.c (error_verbose_flag): Remove.
	* src/output.c (prepare): Don't output it.
	* src/parse-gram.y (%error-verbose): Treat as %define error_verbose.

data/bison.m4

@@ -332,7 +332,6 @@ m4_define([b4_$3_if],
 # -----------------------------
 # Expand IF-TRUE, if FLAG is true, IF-FALSE otherwise.
 b4_define_flag_if([defines])	        # Whether headers are requested.
-b4_define_flag_if([error_verbose])	# Whether error are verbose.
 b4_define_flag_if([glr])		# Whether a GLR parser is requested.
 b4_define_flag_if([locations])	        # Whether locations are tracked.
 b4_define_flag_if([nondeterministic])	# Whether conflicts should be handled.
@@ -619,30 +618,11 @@ m4_define([b4_percent_define_ifdef],
 	  [$3])])
 
 
-# b4_percent_define_if_define(VARIABLE)
-# -------------------------------------
-# Define b4_VARIABLE_if that executes its $1 or $2 depending whether VARIABLE
-# was %defined.
-m4_define([b4_percent_define_if_define_],
-[m4_define([b4_$1_if], [b4_percent_define_ifdef([$1], [$2], [$3])])])
-m4_define([b4_percent_define_if_define],
-[b4_percent_define_if_define_([$1], $[1], $[2])])
-
 ## --------- ##
 ## Options.  ##
 ## --------- ##
 
 
-# b4_assert_if([IF-ASSERTIONS-ARE-USED], [IF-NOT])
-# b4_lex_symbol_if([IF-YYLEX-RETURNS-A-COMPLETE-SYMBOL], [IF-NOT])
-# b4_variant_if([IF-VARIANT-ARE-USED], [IF-NOT])
-# ----------------------------------------------
-b4_percent_define_if_define([assert])
-b4_percent_define_if_define([lex_symbol])
-b4_percent_define_if_define([variant])
-
-
-
 # b4_percent_define_flag_if(VARIABLE, IF-TRUE, [IF-FALSE])
 # --------------------------------------------------------
 # Mimic muscle_percent_define_flag_if in ../src/muscle_tab.h exactly.  That is,
@@ -666,6 +646,7 @@ m4_define([b4_percent_define_flag_if],
                            [[b4_percent_define_flag_if($1)]])])],
   [b4_fatal([[undefined %%define variable `%s' passed to b4_percent_define_flag_if]], [$1])])])
 
+
 # b4_percent_define_default(VARIABLE, DEFAULT)
 # --------------------------------------------
 # Mimic muscle_percent_define_default in ../src/muscle_tab.h exactly.  That is,
@@ -684,6 +665,30 @@ m4_define([b4_percent_define_default],
                         [[<skeleton default value>:-1.-1]]]])dnl
             m4_define([b4_percent_define_syncline(]$1[)], [[]])])])
 
+
+# b4_percent_define_if_define(VARIABLE)
+# -------------------------------------
+# Define b4_VARIABLE_if that executes its $1 or $2 depending whether
+# VARIABLE was %defined.
+m4_define([b4_percent_define_if_define_],
+[m4_define([b4_$1_if], [b4_percent_define_flag_if([$1], [$2], [$3])])])
+m4_define([b4_percent_define_if_define],
+[b4_percent_define_default([[$1]], [[false]])
+b4_percent_define_if_define_([$1], $[1], $[2])])
+
+
+# b4_assert_if([IF-ASSERTIONS-ARE-USED], [IF-NOT])
+# b4_error_verbose_if([IF-ERRORS-ARE-VERBOSE], [IF-NOT])
+# b4_lex_symbol_if([IF-YYLEX-RETURNS-A-COMPLETE-SYMBOL], [IF-NOT])
+# b4_variant_if([IF-VARIANT-ARE-USED], [IF-NOT])
+# ----------------------------------------------
+b4_percent_define_if_define([assert])
+b4_percent_define_if_define([error_verbose])
+b4_percent_define_if_define([lex_symbol])
+b4_percent_define_if_define([variant])
+
+
+
 # b4_percent_define_check_values(VALUES)
 # --------------------------------------
 # Mimic muscle_percent_define_check_values in ../src/muscle_tab.h exactly

data/glr.c

@@ -232,7 +232,7 @@ b4_defines_if([[#include "@basename(]b4_spec_defines_file[@)"]],
 # undef YYERROR_VERBOSE
 # define YYERROR_VERBOSE 1
 #else
-# define YYERROR_VERBOSE ]b4_error_verbose_flag[
+# define YYERROR_VERBOSE ]b4_error_verbose_if([1], [0])[
 #endif
 
 /* Enabling the token table.  */

data/lalr1.cc

@@ -1,6 +1,6 @@
 # C++ skeleton for Bison
 
-# Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008
+# Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
 # Free Software Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify
@@ -116,7 +116,7 @@ m4_popdef([b4_dollar_dollar])dnl
 
 
 m4_pushdef([b4_copyright_years],
-           [2002, 2003, 2004, 2005, 2006, 2007, 2008])
+           [2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009])
 
 m4_define([b4_parser_class_name],
           [b4_percent_define_get([[parser_class_name]])])
@@ -169,7 +169,7 @@ dnl FIXME: This is wrong, we want computed header guards.
 # undef YYERROR_VERBOSE
 # define YYERROR_VERBOSE 1
 #else
-# define YYERROR_VERBOSE ]b4_error_verbose_flag[
+# define YYERROR_VERBOSE ]b4_error_verbose_if([1], [0])[
 #endif
 
 /* Enabling the token table.  */

data/yacc.c

@@ -2,10 +2,10 @@
 # Yacc compatible skeleton for Bison
 
 # Copyright (C) 1984, 1989, 1990, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
-# 2007, 2008 Free Software Foundation, Inc.
+# 2007, 2008, 2009 Free Software Foundation, Inc.
 
 m4_pushdef([b4_copyright_years],
-[1984, 1989, 1990, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008])
+[1984, 1989, 1990, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009])
 
 # 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
@@ -200,7 +200,7 @@ m4_if(b4_prefix, [yy], [],
 # undef YYERROR_VERBOSE
 # define YYERROR_VERBOSE 1
 #else
-# define YYERROR_VERBOSE ]b4_error_verbose_flag[
+# define YYERROR_VERBOSE ]b4_error_verbose_if([1], [0])[
 #endif
 
 /* Enabling the token table.  */