Bison News
----------
-Changes in version 1.875f:
+Changes in version 2.1a:
-* 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.
+Changes in version 2.1, 2005-09-16:
-Changes in version 1.875e, 2004-12-10:
+* 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.
-* New directive: %initial-action.
- This directive allows the user to run arbitrary code (including
- initializing @$) from yyparse before parsing starts.
+* 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.
-* The option `--report=lookahead' was changed to `--report=look-ahead'.
- The old spelling still works, but is not documented and will be
- removed.
+* 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.
-* 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.
+* 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"'.
-* Goto numbers are no longer arbitrarily limited to 16-bit counts.
+Changes in version 2.0, 2004-12-25:
-Changes in version 1.875d, 2004-05-21:
+* Possibly-incompatible changes
-* 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.
+ - 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.
-* NUL bytes are no longer allowed in Bison string literals, unfortunately.
+ - 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.
-* %token numbers can now be hexadecimal integers, e.g., `%token FOO 0x12d'.
- This is a GNU extension.
+ - Semicolon changes:
+ . 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.
+ - 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.
-* Experimental %destructor support has been added to lalr1.cc.
+ - NUL bytes are no longer allowed in Bison string literals, unfortunately.
-Changes in version 1.875c, 2003-08-25:
+* New features
- (Just bug fixes.)
+ - GLR grammars now support locations.
-Changes in version 1.875b, 2003-06-17:
+ - New directive: %initial-action.
+ This directive allows the user to run arbitrary code (including
+ initializing @$) from yyparse before parsing starts.
-* GLR grammars now support locations.
+ - A new directive "%expect-rr N" specifies the expected number of
+ reduce/reduce conflicts in GLR parsers.
-* 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.
+ - %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.
+
+ - New configure option --disable-yacc, to disable installation of the
+ yacc command and -ly library introduced in 1.875 for POSIX conformance.
-Changes in version 1.875a, 2003-02-01:
+* Bug fixes
-* 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.
+ - 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.
-* New configure option --disable-yacc, to disable installation of the
- yacc command and -ly library introduced in 1.875 for POSIX conformance.
+ - 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:
alloca is used only when compiled with GCC, to avoid portability
problems as on AIX.
+* yyparse now returns 2 if memory is exhausted; formerly it dumped core.
+
* When the generated parser lacks debugging code, YYDEBUG is now 0
(as POSIX requires) instead of being undefined.
-----
-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.
projects / bison.git / blobdiff