X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/6240346aa045e8c0d7da616aca87c9d4d350d369..a17c70f876111f81e2968acfef936b7127660acd:/NEWS diff --git a/NEWS b/NEWS index 9a6a1e14..3bfc1f94 100644 --- a/NEWS +++ b/NEWS @@ -4,14 +4,6 @@ GNU Bison NEWS ** WARNING: Future backward-incompatibilities! - Bison will stop adding a semicolon at the end of the actions (as announced - in the release 2.5): - - 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. @@ -28,6 +20,9 @@ GNU Bison NEWS Support for YYLEX_PARAM and YYPARSE_PARAM is removed (deprecated in Bison 1.875): use %lex-param, %parse-param, or %param. + Missing semicolons at the end of actions are no longer added (as announced + in the release 2.5). + ** Bug fixes *** The epilogue is no longer affected by internal #defines (glr.c) @@ -39,7 +34,7 @@ GNU Bison NEWS int yylex (YYSTYPE *yylval); - This is has been fixed: yylval, yynerrs, yychar, and yylloc are now valid + This is 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) @@ -221,6 +216,11 @@ GNU Bison NEWS bar.y: error: shift/reduce conflicts: 1 found, 0 expected bar.y: error: reduce/reduce conflicts: 2 found, 0 expected +** Incompatibilities with POSIX Yacc + + The 'yacc' category is no longer part of '-Wall', enable it explicitly + with '-Wyacc'. + ** Additional yylex/yyparse arguments The new directive %param declares additional arguments to both yylex and @@ -284,17 +284,33 @@ GNU Bison NEWS It used to be an error only if used in non GLR mode, _and_ if there are reduce/reduce conflicts. -** Token numbering has changed to preserve the user-defined order +** Tokens are numbered in their order of appearance + + Contributed by Valentin Tolmer. + + With '%token A B', A had a number less than the one of B. However, + precedence declarations used to generate a reversed order. This is now + fixed, and introducing tokens with any of %token, %left, %right, + %precedence, or %nonassoc yields the same result. + + When mixing declarations of tokens with a litteral character (e.g., 'a') + or with an identifier (e.g., B) in a precedence declaration, Bison + numbered the litteral characters first. For example + + %right A B 'c' 'd' + + would lead to the tokens declared in this order: 'c' 'd' A B. Again, the + input order is now preserved. - 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. + These changes were made so that one can remove useless precedence and + associativity declarations (i.e., map %nonassoc, %left or %right to + %precedence, or to %token) and get exactly the same output. ** Useless precedence and associativity Contributed by Valentin Tolmer. - When developping and maintaining a grammar, useless associativity and + When developing and maintaining a grammar, useless associativity and precedence directives are common. They can be a nuisance: new ambiguities arising are sometimes masked because their conflicts are resolved due to the extra precedence or associativity information. Furthermore, it can @@ -319,8 +335,8 @@ GNU Bison NEWS %left '*' %% exp: - "num" - | exp '+' "num" + "number" + | exp '+' "number" | exp '*' exp ; @@ -339,7 +355,7 @@ GNU Bison NEWS %precedence '=' %% - exp: "var" '=' "num"; + exp: "var" '=' "number"; will produce a @@ -354,7 +370,7 @@ GNU Bison NEWS %nonassoc '=' %% - exp: "var" '=' "num"; + exp: "var" '=' "number"; The warning is: @@ -511,8 +527,8 @@ GNU Bison NEWS exp: exp '+' exp { $exp = $1 + $3; }; ^^^ - The default behaviour for now is still not to display these unless - explictly asked with -fcaret (or -fall). However, in a later release, it + The default behavior for now is still not to display these unless + explicitly asked with -fcaret (or -fall). However, in a later release, it will be made the default behavior (but may still be deactivated with -fno-caret). @@ -599,7 +615,7 @@ GNU Bison NEWS Other issues in the test suite have been addressed. - Nul characters are correctly displayed in error messages. + Null characters are correctly displayed in error messages. When possible, yylloc is correctly initialized before calling yylex. It is no longer necessary to initialize it in the %initial-action. @@ -2515,7 +2531,12 @@ along with this program. If not, see . LocalWords: Automake TMPDIR LESSEQ ylwrap endif yydebug YYTOKEN YYLSP ival hh LocalWords: extern YYTOKENTYPE TOKENTYPE yytokentype tokentype STYPE lval pdf LocalWords: lang yyoutput dvi html ps POSIX lvalp llocp Wother nterm arg init - LocalWords: TOK calc yyo fval Wconflicts + LocalWords: TOK calc yyo fval Wconflicts parsers yystackp yyval yynerrs + LocalWords: Théophile Ranquet Santet fno fnone stype associativity Tolmer + LocalWords: Wprecedence Rassoul Wempty Paolo Bonzini parser's Michiel loc + LocalWords: redeclaration sval fcaret reentrant XSLT xsl Wmaybe yyvsp Tedi + LocalWords: pragmas noreturn untyped Rozenman unexpanded Wojciech Polak + LocalWords: Alexandre MERCHANTABILITY Local Variables: mode: outline