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This is used to help the user catch cases where some value gets ovewritten by a new one. This should not happen, as this will probably leak. Unfortunately this uncovered a bug in the C++ parser itself: the lookahead value was not destroyed between two calls to yylex. For instance if the previous lookahead was a std::string, and then an int, then the value of the std::string was correctly taken (i.e., the lookahead was now an empty string), but std::string structure itself was not reclaimed. This is now done in variant::build(other&) (which is used to take the value of the lookahead): other is not only stolen from its value, it is also destroyed. This incurs a new performance penalty of a few percent, and union becomes faster again. * data/lalr1-fusion.cc (variant::build(other&)): Destroy other. (b4_variant_if): New. (variant::built): New. Use it whereever the status of the variant changes. * etc/bench.pl.in: Check the penalty of %define assert.
-*- outline -*- This directory contains Bison skeletons: the general shapes of the different parser kinds, that are specialized for specific grammars by the bison program. Currently, there are only three supported skeletons: - yacc.c It used to be named bison.simple: it corresponds to C Yacc compatible LALR(1) parsers. - lalr1.cc Produces a C++ parser class. It is still very experimental, and not yet supported. Please, subscribe to bison-patches@gnu.org. - glr.c A Generalized LR C parser based on Bison's LALR(1) tables. These skeletons are the only ones supported by the Bison team. Because the interface between skeletons and the bison program is not finished, *we are not bound to it*. In particular, Bison is not mature enough for us to consider that ``foreign skeletons'' are supported. ----- Copyright (C) 2002 Free Software Foundation, Inc. This file is part of GNU Bison. 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/>.