NEWS

   1 Bison News
   2 ----------
   3
   4 Changes in version 1.49a:
   5
   6 * False `Token not used' report fixed.
   7   On a grammar such as
   8
   9            %token useless useful
  10            %%
  11            exp: '0' %prec useful;
  12
  13   where a token was used to set the precedence of the last rule,
  14   bison reported both `useful' and `useless' as useless tokens.
  15
  16 * Revert the C++ namespace changes introduced in 1.31, as they caused too
  17   many portability hassles.
  18
  19 * Items overflow
  20   Bison no longer dumps core when there are too many items, it just
  21   dies.
  22
  23 * Token end-of-file
  24   The token end of file may be specified by the user, in which case,
  25   the user symbol is used in the reports, the graphs, and the verbose
  26   error messages instead of `$', which remains being the defaults.
  27   For instance
  28      %token YYEOF 0
  29   or
  30      %token YYEOF 0 "end of file"
  31 \f
  32 Changes in version 1.31, 2002-01-14:
  33
  34 * Many Bug Fixes
  35
  36 * GNU Gettext and %expect
  37   GNU Gettext asserts 10 s/r conflicts, but there are 7.  Now that
  38   Bison dies on incorrect %expectations, we fear there will be
  39   too many bug reports for Gettext, so _for the time being_, %expect
  40   does not trigger an error when the input file is named `plural.y'.
  41
  42 * Use of alloca in parsers
  43   If YYSTACK_USE_ALLOCA is defined to 0, then the parsers will use
  44   malloc exclusively.  Since 1.29, but was not NEWS'ed.
  45
  46   alloca is used only when compiled with GCC, to avoid portability
  47   problems as on AIX.
  48
  49 * When the generated parser lacks debugging code, YYDEBUG is now 0
  50   (as POSIX requires) instead of being undefined.
  51
  52 * User Actions
  53   Bison has always permitted actions such as { $$ = $1 }: it adds the
  54   ending semicolon.  Now if in Yacc compatibility mode, the semicolon
  55   is no longer output: one has to write { $$ = $1; }.
  56
  57 * Better C++ compliance
  58   The output parsers try to respect C++ namespaces.
  59
  60 * Reduced Grammars
  61   Fixed bugs when reporting useless nonterminals.
  62
  63 * 64 bit hosts
  64   The parsers work properly on 64 bit hosts.
  65
  66 * Error messages
  67   Some calls to strerror resulted in scrambled or missing error messages.
  68
  69 * %expect
  70   When the number of shift/reduce conflicts is correct, don't issue
  71   any warning.
  72
  73 * The verbose report includes the rule line numbers.
  74
  75 * Rule line numbers are fixed in traces.
  76
  77 * Swedish translation
  78
  79 * Parse errors
  80   Verbose parse error messages from the parsers are better looking.
  81   Before: parse error: unexpected `'/'', expecting `"number"' or `'-'' or `'(''
  82      Now: parse error: unexpected '/', expecting "number" or '-' or '('
  83
  84 * Fixed parser memory leaks.
  85   When the generated parser was using malloc to extend its stacks, the
  86   previous allocations were not freed.
  87
  88 * Fixed verbose output file.
  89   Some newlines were missing.
  90   Some conflicts in state descriptions were missing.
  91
  92 * Fixed conflict report.
  93   Option -v was needed to get the result.
  94
  95 * %expect
  96   Was not used.
  97   Mismatches are errors, not warnings.
  98
  99 * Fixed incorrect processing of some invalid input.
 100
 101 * Fixed CPP guards: 9foo.h uses BISON_9FOO_H instead of 9FOO_H.
 102
 103 * Fixed some typos in the documentation.
 104
 105 * %token MY_EOF 0 is supported.
 106   Before, MY_EOF was silently renumbered as 257.
 107
 108 * doc/refcard.tex is updated.
 109
 110 * %output, %file-prefix, %name-prefix.
 111   New.
 112
 113 * --output
 114   New, aliasing `--output-file'.
 115 \f
 116 Changes in version 1.30:
 117
 118 * `--defines' and `--graph' have now an optionnal argument which is the
 119   output file name. `-d' and `-g' do not change, they do not take any
 120   argument.
 121
 122 * `%source_extension' and `%header_extension' are removed, failed
 123   experiment.
 124
 125 * Portability fixes.
 126 \f
 127 Changes in version 1.29, 2001-09-07:
 128
 129 * The output file does not define const, as this caused problems when used
 130   with common autoconfiguration schemes.  If you still use ancient compilers
 131   that lack const, compile with the equivalent of the C compiler option
 132   `-Dconst='.  autoconf's AC_C_CONST macro provides one way to do this.
 133
 134 * Added `-g' and `--graph'.
 135
 136 * The Bison manual is now distributed under the terms of the GNU FDL.
 137
 138 * The input and the output files has automatically a similar extension.
 139
 140 * Russian translation added.
 141
 142 * NLS support updated; should hopefully be less troublesome.
 143
 144 * Added the old Bison reference card.
 145
 146 * Added `--locations' and `%locations'.
 147
 148 * Added `-S' and `--skeleton'.
 149
 150 * `%raw', `-r', `--raw' is disabled.
 151
 152 * Special characters are escaped when output.  This solves the problems
 153   of the #line lines with path names including backslashes.
 154
 155 * New directives.
 156   `%yacc', `%fixed_output_files', `%defines', `%no_parser', `%verbose',
 157   `%debug', `%source_extension' and `%header_extension'.
 158
 159 * @$
 160   Automatic location tracking.
 161 \f
 162 Changes in version 1.28, 1999-07-06:
 163
 164 * Should compile better now with K&R compilers.
 165
 166 * Added NLS.
 167
 168 * Fixed a problem with escaping the double quote character.
 169
 170 * There is now a FAQ.
 171 \f
 172 Changes in version 1.27:
 173
 174 * The make rule which prevented bison.simple from being created on
 175   some systems has been fixed.
 176 \f
 177 Changes in version 1.26:
 178
 179 * Bison now uses automake.
 180
 181 * New mailing lists: <bug-bison@gnu.org> and <help-bison@gnu.org>.
 182
 183 * Token numbers now start at 257 as previously documented, not 258.
 184
 185 * Bison honors the TMPDIR environment variable.
 186
 187 * A couple of buffer overruns have been fixed.
 188
 189 * Problems when closing files should now be reported.
 190
 191 * Generated parsers should now work even on operating systems which do
 192   not provide alloca().
 193 \f
 194 Changes in version 1.25, 1995-10-16:
 195
 196 * Errors in the input grammar are not fatal; Bison keeps reading
 197 the grammar file, and reports all the errors found in it.
 198
 199 * Tokens can now be specified as multiple-character strings: for
 200 example, you could use "<=" for a token which looks like <=, instead
 201 of chosing a name like LESSEQ.
 202
 203 * The %token_table declaration says to write a table of tokens (names
 204 and numbers) into the parser file.  The yylex function can use this
 205 table to recognize multiple-character string tokens, or for other
 206 purposes.
 207
 208 * The %no_lines declaration says not to generate any #line preprocessor
 209 directives in the parser file.
 210
 211 * The %raw declaration says to use internal Bison token numbers, not
 212 Yacc-compatible token numbers, when token names are defined as macros.
 213
 214 * The --no-parser option produces the parser tables without including
 215 the parser engine; a project can now use its own parser engine.
 216 The actions go into a separate file called NAME.act, in the form of
 217 a switch statement body.
 218 \f
 219 Changes in version 1.23:
 220
 221 The user can define YYPARSE_PARAM as the name of an argument to be
 222 passed into yyparse.  The argument should have type void *.  It should
 223 actually point to an object.  Grammar actions can access the variable
 224 by casting it to the proper pointer type.
 225
 226 Line numbers in output file corrected.
 227 \f
 228 Changes in version 1.22:
 229
 230 --help option added.
 231 \f
 232 Changes in version 1.20:
 233
 234 Output file does not redefine const for C++.
 235
 236 Local Variables:
 237 mode: outline
 238 End: