Files
bison/data/c++.m4
Akim Demaille ef51bfa744 c++: use nullptr for C++11.
C++11 introduces "nullptr" which plays the role of C's NULL, in
replacement of "0".  Fix the C++ skeletons to avoid warnings about
uses of "0" in place of "nullptr", and improve C skeletons to also use
this "nullptr" when compiled with a C++11 compiler.

* configure.ac: More C++ warnings.
* NEWS (2.5.1): Document this.
* data/c++.m4, data/c.m4 (b4_null_define): New.
(b4_null): Use YY_NULL instead of 0.
* data/glr.c, data/lalr1.cc, data/location.cc, data/yacc.c:
Call b4_null_define/b4_null where appropriate.
Use YY_NULL instead of NULL.
* data/location.cc (initialize): Accept a default argument,
YY_NULL.
* tests/actions.at, tests/calc.at: Adjust.

* data/glr.c, lib/libiberty.h, src/system.h (__attribute__):
Do not disable it when __STRICT_ANSI__ is defined, as, for
instance, it disables the __attribute__((unused)) which
protects us from some compiler warnings.
This was already done elsewhere in Bison, in 2001, see
4a0d893695.
* tests/regression.at: Adjust output.
2012-03-31 11:12:28 +02:00

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-*- Autoconf -*-
# C++ skeleton for Bison
# Copyright (C) 2002-2012 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
# 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
# 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 this program. If not, see <http://www.gnu.org/licenses/>.
m4_include(b4_pkgdatadir/[c.m4])
## ---------------- ##
## Default values. ##
## ---------------- ##
# Default parser class name.
b4_percent_define_default([[parser_class_name]], [[parser]])
# Don't do that so that we remember whether we're using a user
# request, or the default value.
#
# b4_percent_define_default([[location_type]], [[location]])
b4_percent_define_default([[filename_type]], [[std::string]])
b4_percent_define_default([[namespace]], m4_defn([b4_prefix]))
b4_percent_define_default([[global_tokens_and_yystype]], [[false]])
b4_percent_define_default([[define_location_comparison]],
[m4_if(b4_percent_define_get([[filename_type]]),
[std::string], [[true]], [[false]])])
## ----------- ##
## Namespace. ##
## ----------- ##
m4_define([b4_namespace_ref], [b4_percent_define_get([[namespace]])])
# Don't permit an empty b4_namespace_ref. Any `::parser::foo' appended to it
# would compile as an absolute reference with `parser' in the global namespace.
# b4_namespace_open would open an anonymous namespace and thus establish
# internal linkage. This would compile. However, it's cryptic, and internal
# linkage for the parser would be specified in all translation units that
# include the header, which is always generated. If we ever need to permit
# internal linkage somehow, surely we can find a cleaner approach.
m4_if(m4_bregexp(b4_namespace_ref, [^[ ]*$]), [-1], [],
[b4_complain_at(b4_percent_define_get_loc([[namespace]]),
[[namespace reference is empty]])])
# Instead of assuming the C++ compiler will do it, Bison should reject any
# invalid b4_namepsace_ref that would be converted to a valid
# b4_namespace_open. The problem is that Bison doesn't always output
# b4_namespace_ref to uncommented code but should reserve the ability to do so
# in future releases without risking breaking any existing user grammars.
# Specifically, don't allow empty names as b4_namespace_open would just convert
# those into anonymous namespaces, and that might tempt some users.
m4_if(m4_bregexp(b4_namespace_ref, [::[ ]*::]), [-1], [],
[b4_complain_at(b4_percent_define_get_loc([[namespace]]),
[[namespace reference has consecutive "::"]])])
m4_if(m4_bregexp(b4_namespace_ref, [::[ ]*$]), [-1], [],
[b4_complain_at(b4_percent_define_get_loc([[namespace]]),
[[namespace reference has a trailing "::"]])])
m4_define([b4_namespace_open],
[b4_user_code([b4_percent_define_get_syncline([[namespace]])
[namespace ]m4_bpatsubst(m4_dquote(m4_bpatsubst(m4_dquote(b4_namespace_ref),
[^\(.\)[ ]*::], [\1])),
[::], [ { namespace ])[ {]])])
m4_define([b4_namespace_close],
[b4_user_code([b4_percent_define_get_syncline([[namespace]])
m4_bpatsubst(m4_dquote(m4_bpatsubst(m4_dquote(b4_namespace_ref[ ]),
[^\(.\)[ ]*\(::\)?\([^][:]\|:[^:]\)*],
[\1])),
[::\([^][:]\|:[^:]\)*], [} ])[} // ]b4_namespace_ref])])
# b4_token_enums(LIST-OF-PAIRS-TOKEN-NAME-TOKEN-NUMBER)
# -----------------------------------------------------
# Output the definition of the tokens as enums.
m4_define([b4_token_enums],
[/* Tokens. */
enum yytokentype {
m4_map_sep([ b4_token_enum], [,
],
[$@])
};
])
## ----------------- ##
## Semantic Values. ##
## ----------------- ##
# b4_lhs_value([TYPE])
# --------------------
# Expansion of $<TYPE>$.
m4_define([b4_lhs_value],
[(yyval[]m4_ifval([$1], [.$1]))])
# b4_rhs_value(RULE-LENGTH, NUM, [TYPE])
# --------------------------------------
# Expansion of $<TYPE>NUM, where the current rule has RULE-LENGTH
# symbols on RHS.
m4_define([b4_rhs_value],
[(yysemantic_stack_@{($1) - ($2)@}m4_ifval([$3], [.$3]))])
# b4_lhs_location()
# -----------------
# Expansion of @$.
m4_define([b4_lhs_location],
[(yyloc)])
# b4_rhs_location(RULE-LENGTH, NUM)
# ---------------------------------
# Expansion of @NUM, where the current rule has RULE-LENGTH symbols
# on RHS.
m4_define([b4_rhs_location],
[(yylocation_stack_@{($1) - ($2)@})])
# b4_parse_param_decl
# -------------------
# Extra formal arguments of the constructor.
# Change the parameter names from "foo" into "foo_yyarg", so that
# there is no collision bw the user chosen attribute name, and the
# argument name in the constructor.
m4_define([b4_parse_param_decl],
[m4_ifset([b4_parse_param],
[m4_map_sep([b4_parse_param_decl_1], [, ], [b4_parse_param])])])
m4_define([b4_parse_param_decl_1],
[$1_yyarg])
# b4_parse_param_cons
# -------------------
# Extra initialisations of the constructor.
m4_define([b4_parse_param_cons],
[m4_ifset([b4_parse_param],
[
b4_cc_constructor_calls(b4_parse_param)])])
m4_define([b4_cc_constructor_calls],
[m4_map_sep([b4_cc_constructor_call], [,
], [$@])])
m4_define([b4_cc_constructor_call],
[$2 ($2_yyarg)])
# b4_parse_param_vars
# -------------------
# Extra instance variables.
m4_define([b4_parse_param_vars],
[m4_ifset([b4_parse_param],
[
/* User arguments. */
b4_cc_var_decls(b4_parse_param)])])
m4_define([b4_cc_var_decls],
[m4_map_sep([b4_cc_var_decl], [
], [$@])])
m4_define([b4_cc_var_decl],
[ $1;])