X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/0906b12cd56f9777fb684b8a257a0e56c090a93c..93561c21e8d42aad487fd81ef1f79c5ba3f494fe:/NEWS diff --git a/NEWS b/NEWS index 7df5d87e..167cc8bd 100644 --- a/NEWS +++ b/NEWS @@ -2,16 +2,60 @@ GNU Bison NEWS * Noteworthy changes in release ?.? (????-??-??) [?] +** Future changes + + Bison will stop adding a semicolon at the end of the actions: + + foo.y:2.22: warning: a ';' might be needed at the end of action code + exp: "num" { $$ = $1 } + ^ + foo.y:2.22: future versions of Bison will not add the ';' + + Like other GNU packages, Bison will start using some of the C99 features + for its own code, especially the definition of variables after statements. + The generated C parsers still aim at C90. + ** Incompatible changes *** Obsolete features - Support for YYFAIL is removed (deprecated in Bison 2.4.2). - Support for yystype and yyltype (instead of YYSTYPE and YYLTYPE) - is removed (deprecated in Bison 1.875). - Support for YYPARSE_PARAM is removed (deprecated in Bison 1.875). + Support for YYFAIL is removed (deprecated in Bison 2.4.2): use YYERROR. + + Support for yystype and yyltype is removed (deprecated in Bison 1.875): + use YYSTYPE and YYLTYPE. + + Support for YYLEX_PARAM and YYPARSE_PARAM is removed (deprecated in Bison + 1.875): use %lex-param, %parse-param, or %param. + +** Bug fixes + +*** The epilogue is no longer affected by internal #defines + + The glr.c skeleton uses defines such as #define yylval (yystackp->yyval) in + generated code. These weren't properly undefined before the inclusion of + the user epilogue, so functions such as the following were butchered by the + preprocessor expansion: -** Warnings + int yylex (YYSTYPE *yylval); + + This is has been fixed: yylval, yynerrs, yychar, and yylloc are now valid + identifiers for user-provided variables. + +*** stdio.h is no longer needed when locations are enabled (yacc.c) + + Changes in Bison 2.7 introduced a dependency on FILE and fprintf when + locations are enabled. This is fixed. + +** Diagnostics reported by Bison + + Most of these features were contributed by Théophile Ranquet and Victor + Santet. + +*** Carets + + Version 2.7 introduced caret errors, for a prettier output. These are now + activated by default. The old format can still be used by invoking Bison + with -fno-caret (or -fnone). *** Enhancements of the -Werror option @@ -170,6 +214,8 @@ GNU Bison NEWS ** Java skeleton improvements + Contributed by Paolo Bonzini. + The constants for token names were moved to the Lexer interface. Also, it is possible to add code to the parser's constructors using "%code init" and "%define init_throws". @@ -195,6 +241,16 @@ GNU Bison NEWS used by the scanner, or rejecting invalid combinations from a factory invoked by the user actions). +** Renamed %define variables + + The following variables have been renamed for consistency. Backward + compatibility is ensured, but upgrading is recommended. + + lr.default-reductions -> lr.default-reduction + lr.keep-unreachable-states -> lr.keep-unreachable-state + namespace -> api.namespace + stype -> api.value.type + ** Variable api.token.prefix The variable api.token.prefix changes the way tokens are identified in @@ -211,15 +267,6 @@ GNU Bison NEWS use these prefixed token names, although the grammar itself still uses the short names (as in the sample rule given above). -** Renamed %define variables - - The following variables have been renamed for consistency. Backward - compatibility is ensured, but upgrading is recommended. - - lr.default-reductions -> lr.default-reduction - lr.keep-unreachable-states -> lr.keep-unreachable-state - namespace -> api.namespace - ** Variable parse.error This variable controls the verbosity of error messages. The use of the @@ -228,6 +275,8 @@ GNU Bison NEWS ** Semantic predicates + Contributed by Paul Hilfinger. + The new, experimental, semantic-predicate feature allows actions of the form "%?{ BOOLEAN-EXPRESSION }", which cause syntax errors (as for YYERROR) if the expression evaluates to 0, and are evaluated immediately @@ -240,17 +289,20 @@ GNU Bison NEWS It used to be an error only if used in non GLR mode, _and_ if there are reduce/reduce conflicts. -* Noteworthy changes in release ?.? (????-??-??) [?] +** Token numbering has changed to preserve the user-defined order -** %language is no longer an experimental feature. + When declaring %token A B, the numbering for A is inferior to B. Up to now, + when declaring associativity at the same time, with %left (or %right, + %precedence, %nonassoc), B was inferior to A. - The introduction of this feature, in 2.4, was four years ago. The --language - option and the %language directive are no longer experimental. +* Noteworthy changes in release 2.7 (2012-12-12) [stable] ** Bug fixes Warnings about uninitialized yylloc in yyparse have been fixed. + Restored C90 compliance (yet no report was ever made). + ** Diagnostics are improved *** Changes in the format of error messages @@ -748,6 +800,7 @@ GNU Bison NEWS These features are experimental in this version. More user feedback will help to stabilize them. + Contributed by Alex Rozenman. ** IELR(1) and canonical LR(1): @@ -1264,6 +1317,7 @@ GNU Bison NEWS The current Java interface is experimental and may evolve. More user feedback will help to stabilize it. + Contributed by Paolo Bonzini. ** %language @@ -1277,6 +1331,7 @@ GNU Bison NEWS Bison can now generate an XML report of the LALR(1) automaton using the new "--xml" option. The current XML schema is experimental and may evolve. More user feedback will help to stabilize it. + Contributed by Wojciech Polak. ** The grammar file may now specify the name of the parser header file using %defines. For example: @@ -2253,7 +2308,7 @@ Output file does not redefine const for C++. ----- -Copyright (C) 1995-2012 Free Software Foundation, Inc. +Copyright (C) 1995-2013 Free Software Foundation, Inc. This file is part of Bison, the GNU Parser Generator.