Bison News
----------
-Changes in version 1.875f:
+Changes in version 2.0b, 2005-07-24:
-* Bison-generated parsers no longer default to using the alloca function
- (when available) to extend the parser stack, due to widespread
- problems in unchecked stack-overflow detection. You can "#define
- YYSTACK_USE_ALLOCA 1" to use alloca anyway, but please read the
- manual to determine safe values for YYMAXDEPTH in that case.
+* Bison-generated parsers now support the translation of diagnostics like
+ "syntax error" into languages other than English. The default
+ language is still English. For details, please see the new
+ Internationalization section of the Bison manual. Software
+ distributors should also see the new PACKAGING file. Thanks to
+ Bruno Haible for this new feature.
-Changes in version 1.875e, 2004-12-10:
+* Wording in the Bison-generated parsers has been changed slightly to
+ simplify translation. In particular, the message "memory exhausted"
+ has replaced "parser stack overflow", as the old message was not
+ always accurate for modern Bison-generated parsers.
-* New directive: %initial-action.
- This directive allows the user to run arbitrary code (including
- initializing @$) from yyparse before parsing starts.
+* Destructors are now called when the parser aborts, for all symbols left
+ behind on the stack. Also, the start symbol is now destroyed after a
+ successful parse. In both cases, the behavior was formerly inconsistent.
-* The option `--report=lookahead' was changed to `--report=look-ahead'.
- The old spelling still works, but is not documented and will be
- removed.
+* The yytname array now contains the same contents that it did in 2.0,
+ undoing an incompatible and undocumented change made in 2.0a.
-* Error token location.
- During error recovery, the location of the syntax error is updated
- to cover the whole sequence covered by the error token: it includes
- the shifted symbols thrown away during the first part of the error
- recovery, and the lookahead rejected during the second part.
+Changes in version 2.0a, 2005-05-22:
-* Goto numbers are no longer arbitrarily limited to 16-bit counts.
+* When generating verbose diagnostics, Bison-generated parsers no longer
+ quote the literal strings associated with tokens. For example, for
+ a syntax error associated with '%token NUM "number"' they might
+ print 'syntax error, unexpected number' instead of 'syntax error,
+ unexpected "number"'.
-Changes in version 1.875d, 2004-05-21:
+Changes in version 2.0, 2004-12-25:
-* Unescaped newlines are no longer allowed in character constants or
- string literals. They were never portable, and GCC 3.4.0 has
- dropped support for them. Better diagnostics are now generated if
- forget a closing quote.
+* Possibly-incompatible changes
-* NUL bytes are no longer allowed in Bison string literals, unfortunately.
+ - Bison-generated parsers no longer default to using the alloca function
+ (when available) to extend the parser stack, due to widespread
+ problems in unchecked stack-overflow detection. You can "#define
+ YYSTACK_USE_ALLOCA 1" to require the use of alloca, but please read
+ the manual to determine safe values for YYMAXDEPTH in that case.
-* %token numbers can now be hexadecimal integers, e.g., `%token FOO 0x12d'.
- This is a GNU extension.
+ - Error token location.
+ During error recovery, the location of the syntax error is updated
+ to cover the whole sequence covered by the error token: it includes
+ the shifted symbols thrown away during the first part of the error
+ recovery, and the lookahead rejected during the second part.
-* A new directive "%expect-rr N" specifies the expected number of
- reduce/reduce conflicts in GLR parsers.
+ - Semicolon changes:
+ . Stray semicolons are no longer allowed at the start of a grammar.
+ . Semicolons are now required after in-grammar declarations.
-* Experimental %destructor support has been added to lalr1.cc.
+ - Unescaped newlines are no longer allowed in character constants or
+ string literals. They were never portable, and GCC 3.4.0 has
+ dropped support for them. Better diagnostics are now generated if
+ forget a closing quote.
-Changes in version 1.875c, 2003-08-25:
+ - NUL bytes are no longer allowed in Bison string literals, unfortunately.
- (Just bug fixes.)
+* New features
-Changes in version 1.875b, 2003-06-17:
+ - GLR grammars now support locations.
-* GLR grammars now support locations.
+ - New directive: %initial-action.
+ This directive allows the user to run arbitrary code (including
+ initializing @$) from yyparse before parsing starts.
-* Semicolon changes:
- - Semicolons are now allowed before "|" in grammar rules, as POSIX requires.
- - Stray semicolons are no longer allowed at the start of a grammar.
- - Semicolons are now required after in-grammar declarations.
+ - A new directive "%expect-rr N" specifies the expected number of
+ reduce/reduce conflicts in GLR parsers.
+
+ - %token numbers can now be hexadecimal integers, e.g., `%token FOO 0x12d'.
+ This is a GNU extension.
+
+ - The option `--report=lookahead' was changed to `--report=look-ahead'.
+ The old spelling still works, but is not documented and will be
+ removed.
+
+ - Experimental %destructor support has been added to lalr1.cc.
-Changes in version 1.875a, 2003-02-01:
+ - New configure option --disable-yacc, to disable installation of the
+ yacc command and -ly library introduced in 1.875 for POSIX conformance.
-* For now, %expect-count violations are now just warnings, not errors.
- This is for compatibility with Bison 1.75 and earlier (when there are
- reduce/reduce conflicts) and with Bison 1.30 and earlier (when there
- are too many or too few shift/reduce conflicts). However, in future
- versions of Bison we plan to improve the %expect machinery so that
- these violations will become errors again.
+* Bug fixes
-* New configure option --disable-yacc, to disable installation of the
- yacc command and -ly library introduced in 1.875 for POSIX conformance.
+ - For now, %expect-count violations are now just warnings, not errors.
+ This is for compatibility with Bison 1.75 and earlier (when there are
+ reduce/reduce conflicts) and with Bison 1.30 and earlier (when there
+ are too many or too few shift/reduce conflicts). However, in future
+ versions of Bison we plan to improve the %expect machinery so that
+ these violations will become errors again.
+
+ - Within Bison itself, numbers (e.g., goto numbers) are no longer
+ arbitrarily limited to 16-bit counts.
+
+ - Semicolons are now allowed before "|" in grammar rules, as POSIX requires.
\f
Changes in version 1.875, 2003-01-01:
-----
-Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
+Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
Free Software Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
You should have received a copy of the GNU General Public License
along with autoconf; see the file COPYING. If not, write to
-the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA.
+the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+Boston, MA 02110-1301, USA.