NEWS

   1 Bison News
   2 ----------
   3
   4 Changes in version 1.34, 2002-03-12:
   5
   6 * File name clashes are detected
   7   $ bison foo.y -d -o foo.x
   8   fatal error: header and parser would be both named `foo.x'
   9
  10 * A missing `;' ending a rule triggers a warning
  11   In accordance with POSIX, and in agreement with other
  12   Yacc implementations, Bison will mandate this semicolon in a near
  13   future.  This eases the implementation of a Bison parser of Bison
  14   grammars by making this grammar LALR(1) instead of LR(2).  To
  15   facilitate the transition, this release introduces a warning.
  16
  17 * Revert the C++ namespace changes introduced in 1.31, as they caused too
  18   many portability hassles.
  19
  20 * DJGPP support added.
  21
  22 * Fix test suite portability problems.
  23 \f
  24 Changes in version 1.33, 2002-02-07:
  25
  26 * Fix C++ issues
  27   Groff could not be compiled for the definition of size_t was lacking
  28   under some conditions.
  29
  30 * Catch invalid @n
  31   As is done with $n.
  32 \f
  33 Changes in version 1.32, 2002-01-23:
  34
  35 * Fix Yacc output file names
  36
  37 * Portability fixes
  38
  39 * Italian, Dutch translations
  40 \f
  41 Changes in version 1.31, 2002-01-14:
  42
  43 * Many Bug Fixes
  44
  45 * GNU Gettext and %expect
  46   GNU Gettext asserts 10 s/r conflicts, but there are 7.  Now that
  47   Bison dies on incorrect %expectations, we fear there will be
  48   too many bug reports for Gettext, so _for the time being_, %expect
  49   does not trigger an error when the input file is named `plural.y'.
  50
  51 * Use of alloca in parsers
  52   If YYSTACK_USE_ALLOCA is defined to 0, then the parsers will use
  53   malloc exclusively.  Since 1.29, but was not NEWS'ed.
  54
  55   alloca is used only when compiled with GCC, to avoid portability
  56   problems as on AIX.
  57
  58 * When the generated parser lacks debugging code, YYDEBUG is now 0
  59   (as POSIX requires) instead of being undefined.
  60
  61 * User Actions
  62   Bison has always permitted actions such as { $$ = $1 }: it adds the
  63   ending semicolon.  Now if in Yacc compatibility mode, the semicolon
  64   is no longer output: one has to write { $$ = $1; }.
  65
  66 * Better C++ compliance
  67   The output parsers try to respect C++ namespaces.
  68   [This turned out to be a failed experiment, and it was reverted later.]
  69
  70 * Reduced Grammars
  71   Fixed bugs when reporting useless nonterminals.
  72
  73 * 64 bit hosts
  74   The parsers work properly on 64 bit hosts.
  75
  76 * Error messages
  77   Some calls to strerror resulted in scrambled or missing error messages.
  78
  79 * %expect
  80   When the number of shift/reduce conflicts is correct, don't issue
  81   any warning.
  82
  83 * The verbose report includes the rule line numbers.
  84
  85 * Rule line numbers are fixed in traces.
  86
  87 * Swedish translation
  88
  89 * Parse errors
  90   Verbose parse error messages from the parsers are better looking.
  91   Before: parse error: unexpected `'/'', expecting `"number"' or `'-'' or `'(''
  92      Now: parse error: unexpected '/', expecting "number" or '-' or '('
  93
  94 * Fixed parser memory leaks.
  95   When the generated parser was using malloc to extend its stacks, the
  96   previous allocations were not freed.
  97
  98 * Fixed verbose output file.
  99   Some newlines were missing.
 100   Some conflicts in state descriptions were missing.
 101
 102 * Fixed conflict report.
 103   Option -v was needed to get the result.
 104
 105 * %expect
 106   Was not used.
 107   Mismatches are errors, not warnings.
 108
 109 * Fixed incorrect processing of some invalid input.
 110
 111 * Fixed CPP guards: 9foo.h uses BISON_9FOO_H instead of 9FOO_H.
 112
 113 * Fixed some typos in the documentation.
 114
 115 * %token MY_EOF 0 is supported.
 116   Before, MY_EOF was silently renumbered as 257.
 117
 118 * doc/refcard.tex is updated.
 119
 120 * %output, %file-prefix, %name-prefix.
 121   New.
 122
 123 * --output
 124   New, aliasing `--output-file'.
 125 \f
 126 Changes in version 1.30, 2001-10-26:
 127
 128 * `--defines' and `--graph' have now an optionnal argument which is the
 129   output file name. `-d' and `-g' do not change, they do not take any
 130   argument.
 131
 132 * `%source_extension' and `%header_extension' are removed, failed
 133   experiment.
 134
 135 * Portability fixes.
 136 \f
 137 Changes in version 1.29, 2001-09-07:
 138
 139 * The output file does not define const, as this caused problems when used
 140   with common autoconfiguration schemes.  If you still use ancient compilers
 141   that lack const, compile with the equivalent of the C compiler option
 142   `-Dconst='.  autoconf's AC_C_CONST macro provides one way to do this.
 143
 144 * Added `-g' and `--graph'.
 145
 146 * The Bison manual is now distributed under the terms of the GNU FDL.
 147
 148 * The input and the output files has automatically a similar extension.
 149
 150 * Russian translation added.
 151
 152 * NLS support updated; should hopefully be less troublesome.
 153
 154 * Added the old Bison reference card.
 155
 156 * Added `--locations' and `%locations'.
 157
 158 * Added `-S' and `--skeleton'.
 159
 160 * `%raw', `-r', `--raw' is disabled.
 161
 162 * Special characters are escaped when output.  This solves the problems
 163   of the #line lines with path names including backslashes.
 164
 165 * New directives.
 166   `%yacc', `%fixed_output_files', `%defines', `%no_parser', `%verbose',
 167   `%debug', `%source_extension' and `%header_extension'.
 168
 169 * @$
 170   Automatic location tracking.
 171 \f
 172 Changes in version 1.28, 1999-07-06:
 173
 174 * Should compile better now with K&R compilers.
 175
 176 * Added NLS.
 177
 178 * Fixed a problem with escaping the double quote character.
 179
 180 * There is now a FAQ.
 181 \f
 182 Changes in version 1.27:
 183
 184 * The make rule which prevented bison.simple from being created on
 185   some systems has been fixed.
 186 \f
 187 Changes in version 1.26:
 188
 189 * Bison now uses automake.
 190
 191 * New mailing lists: <bug-bison@gnu.org> and <help-bison@gnu.org>.
 192
 193 * Token numbers now start at 257 as previously documented, not 258.
 194
 195 * Bison honors the TMPDIR environment variable.
 196
 197 * A couple of buffer overruns have been fixed.
 198
 199 * Problems when closing files should now be reported.
 200
 201 * Generated parsers should now work even on operating systems which do
 202   not provide alloca().
 203 \f
 204 Changes in version 1.25, 1995-10-16:
 205
 206 * Errors in the input grammar are not fatal; Bison keeps reading
 207 the grammar file, and reports all the errors found in it.
 208
 209 * Tokens can now be specified as multiple-character strings: for
 210 example, you could use "<=" for a token which looks like <=, instead
 211 of chosing a name like LESSEQ.
 212
 213 * The %token_table declaration says to write a table of tokens (names
 214 and numbers) into the parser file.  The yylex function can use this
 215 table to recognize multiple-character string tokens, or for other
 216 purposes.
 217
 218 * The %no_lines declaration says not to generate any #line preprocessor
 219 directives in the parser file.
 220
 221 * The %raw declaration says to use internal Bison token numbers, not
 222 Yacc-compatible token numbers, when token names are defined as macros.
 223
 224 * The --no-parser option produces the parser tables without including
 225 the parser engine; a project can now use its own parser engine.
 226 The actions go into a separate file called NAME.act, in the form of
 227 a switch statement body.
 228 \f
 229 Changes in version 1.23:
 230
 231 The user can define YYPARSE_PARAM as the name of an argument to be
 232 passed into yyparse.  The argument should have type void *.  It should
 233 actually point to an object.  Grammar actions can access the variable
 234 by casting it to the proper pointer type.
 235
 236 Line numbers in output file corrected.
 237 \f
 238 Changes in version 1.22:
 239
 240 --help option added.
 241 \f
 242 Changes in version 1.20:
 243
 244 Output file does not redefine const for C++.
 245
 246 Local Variables:
 247 mode: outline
 248 End: