X-Spam-Check-By: sourceware.org Date: Sun, 9 Jul 2006 15:04:16 -0400 From: Christopher Faylor To: cygwin AT cygwin DOT com Subject: [ANNOUNCEMENT] Updated: bison-2.3-1 Message-Id: Reply-To: cygwin AT cygwin DOT com References: <20030308234440 DOT GA8132 AT redhat DOT com> <20060222053418 DOT GA15103 AT trixie DOT casa DOT cgf DOT cx> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060222053418.GA15103@trixie.casa.cgf.cx> User-Agent: Mutt/1.5.11 Reply-To: The Cygwin Mailing List X-Mailer: Perl5 Mail::Internet v1.74 X-IsSubscribed: yes Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm Precedence: bulk List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com I've made a new version of 'bison' available for download. This updates the package to the latest version available from ftp.gnu.org. I've included the relevant portions of the Bison NEWS file at the end of this message. For a brief description of this package, see http://cygwin.com/packages/ . To update your installation, click on the "Install Cygwin now" link on the http://cygwin.com/ web page. This downloads setup.exe to your system. Run setup.exe to install or update the bison package. If you have questions or comments, please send them to the Cygwin mailing list. I would appreciate it if you would use the mailing list rather than emailing me directly. *** CYGWIN-ANNOUNCE UNSUBSCRIBE INFO *** If you want to unsubscribe from the cygwin-announce mailing list, look at the "List-Unsubscribe: " tag in the email header of this message. Send email to the address specified there. It will be in the format: cygwin-announce-unsubscribe-you=yourdomain DOT com AT cygwin DOT com If you need more information on unsubscribing, start reading here: http://sourceware.org/lists.html#unsubscribe-simple Please read *all* of the information on unsubscribing that is available starting at the above URL. cgf Bison News ---------- Changes in version 2.3, 2006-06-05: * GLR grammars should now use `YYRECOVERING ()' instead of `YYRECOVERING', for compatibility with LALR(1) grammars. * It is now documented that any definition of YYSTYPE or YYLTYPE should be to a type name that does not contain parentheses or brackets. Changes in version 2.2, 2006-05-19: * The distribution terms for all Bison-generated parsers now permit using the parsers in nonfree programs. Previously, this permission was granted only for Bison-generated LALR(1) parsers in C. * %name-prefix changes the namespace name in C++ outputs. * The C++ parsers export their token_type. * Bison now allows multiple %union declarations, and concatenates their contents together. * New warning: unused values Right-hand side symbols whose values are not used are reported, if the symbols have destructors. For instance: exp: exp "?" exp ":" exp { $1 ? $1 : $3; } | exp "+" exp ; will trigger a warning about $$ and $5 in the first rule, and $3 in the second ($1 is copied to $$ by the default rule). This example most likely contains three errors, and could be rewritten as: exp: exp "?" exp ":" exp { $$ = $1 ? $3 : $5; free ($1 ? $5 : $3); free ($1); } | exp "+" exp { $$ = $1 ? $1 : $3; if ($1) free ($3); } ; However, if the original actions were really intended, memory leaks and all, the warnings can be suppressed by letting Bison believe the values are used, e.g.: exp: exp "?" exp ":" exp { $1 ? $1 : $3; (void) ($$, $5); } | exp "+" exp { $$ = $1; (void) $3; } ; If there are mid-rule actions, the warning is issued if no action uses it. The following triggers no warning: $1 and $3 are used. exp: exp { push ($1); } '+' exp { push ($3); sum (); }; The warning is intended to help catching lost values and memory leaks. If a value is ignored, its associated memory typically is not reclaimed. * %destructor vs. YYABORT, YYACCEPT, and YYERROR. Destructors are now called when user code invokes YYABORT, YYACCEPT, and YYERROR, for all objects on the stack, other than objects corresponding to the right-hand side of the current rule. * %expect, %expect-rr Incorrect numbers of expected conflicts are now actual errors, instead of warnings. * GLR, YACC parsers. The %parse-params are available in the destructors (and the experimental printers) as per the documentation. * Bison now warns if it finds a stray `$' or `@' in an action. * %require "VERSION" This specifies that the grammar file depends on features implemented in Bison version VERSION or higher. * lalr1.cc: The token and value types are now class members. The tokens were defined as free form enums and cpp macros. YYSTYPE was defined as a free form union. They are now class members: tokens are enumerations of the `yy::parser::token' struct, and the semantic values have the `yy::parser::semantic_type' type. If you do not want or can update to this scheme, the directive `%define "global_tokens_and_yystype" "1"' triggers the global definition of tokens and YYSTYPE. This change is suitable both for previous releases of Bison, and this one. If you wish to update, then make sure older version of Bison will fail using `%require "2.2"'. * DJGPP support added. -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/