*** Enhancements of the -Werror option
The -Werror=CATEGORY option is now recognized, and will treat specified
- warnings as errors. The warnings need not have been explictly activated
- using the -W option, this is similar to what gcc 4.7 does.
+ warnings as errors. The warnings need not have been explicitly activated
+ using the -W option, this is similar to what GCC 4.7 does.
For example, given the following command line, Bison will treat both
- warnings related to POSIX Yacc incompatiblities and S/R conflicts as
+ warnings related to POSIX Yacc incompatibilities and S/R conflicts as
errors (and only those):
$ bison -Werror=yacc,error=conflicts-sr input.y
In the case of warnings treated as errors, the prefix is changed from
"warning: " to "error: ", and the suffix is displayed, in a manner similar
- to gcc, as [-Werror=CATEGORY].
+ to GCC, as [-Werror=CATEGORY].
For instance, where the previous version of Bison would report (and exit
with failure):
use these prefixed token names, although the grammar itself still
uses the short names (as in the sample rule given above).
-** Variable api.namespace
+** Renamed %define variables
- The 'namespace' variable is renamed 'api.namespace'. Backward
+ The following variables have been renamed for consistency. Backward
compatibility is ensured, but upgrading is recommended.
+ lr.default-reductions -> lr.default-reduction
+ lr.keep-unreachable-states -> lr.keep-unreachable-state
+ namespace -> api.namespace
+
** Variable parse.error
This variable controls the verbosity of error messages. The use of the
* Noteworthy changes in release ?.? (????-??-??) [?]
-** Bug fixes
-
- Bugs and portability issues in the test suite have been fixed.
+** %language is no longer an experimental feature.
- Some errors in translations have been addressed, and --help now directs
- users to the appropriate place to report them.
+ The introduction of this feature, in 2.4, was four years ago. The --language
+ option and the %language directive are no longer experimental.
- Stray Info files shipped by accident are removed.
+** New value for %define variable: api.pure full
- Incorrect definitions of YY_, issued by yacc.c when no parser header is
- generated, are removed.
+ The %define variable api.pure requests a pure (reentrant) parser. However,
+ for historical reasons, using it in a location-tracking Yacc parser resulted
+ in an yyerror function that did not take a location as a parameter. With this
+ new value, the user may request a better pure parser, where yyerror does take
+ a location as a parameter (in location-tracking parsers).
- All the generated headers are self-contained.
+ The use of "%define api.pure true" is deprecated in favor of this new
+ "%define api.pure full".
** Changes in the format of error messages
foo.y:5.10-25: result type clash on merge function 'merge': <t3> != <t2>
foo.y:4.13-27: previous declaration
+** Exception safety (lalr1.cc)
+
+ The parse function now catches exceptions, uses the %destructors to
+ release memory (the lookahead symbol and the symbols pushed on the stack)
+ before re-throwing the exception.
+
+ This feature is somewhat experimental. User feedback would be
+ appreciated.
+
+** New %define variable: api.location.type (glr.cc, lalr1.cc, lalr1.java)
+
+ The %define variable api.location.type defines the name of the type to use
+ for locations. When defined, Bison no longer generates the position.hh
+ and location.hh files, nor does the parser will include them: the user is
+ then responsible to define her type.
+
+ This can be used in programs with several parsers to factor their location
+ and position files: let one of them generate them, and the others just use
+ them.
+
+ This feature was actually introduced, but not documented, in Bison 2.5,
+ under the name "location_type" (which is maintained for backward
+ compatibility).
+
+ For consistency, lalr1.java's %define variables location_type and
+ position_type are deprecated in favor of api.location.type and
+ api.position.type.
+
+** Graph improvements in DOT and XSLT
+
+ The graphical presentation of the states is more readable: their shape is
+ now rectangular, the state number is clearly displayed, and the items are
+ numbered and left-justified.
+
+ The reductions are now explicitly represented as transitions to other
+ diamond shaped nodes.
+
+ These changes are present in both --graph output and xml2dot.xsl XSLT
+ processing, with minor (documented) differences.
+
+ Two nodes were added to the documentation: Xml and Graphviz.
+
+* Noteworthy changes in release ?.? (????-??-??) [?]
+
+** Bug fixes
+
+ Warnings about uninitialized yylloc in yyparse have been fixed.
+
+** Documentation
+
+ The sections about shift/reduce and reduce/reduce conflicts resolution
+ have been fixed and extended.
+
+* Noteworthy changes in release 2.6.5 (2012-11-07) [stable]
+
+ We consider compiler warnings about Bison generated parsers to be bugs.
+ Rather than working around them in your own project, please consider
+ reporting them to us.
+
+** Bug fixes
+
+ Warnings about uninitialized yylval and/or yylloc for push parsers with a
+ pure interface have been fixed for GCC 4.0 up to 4.8, and Clang 2.9 to
+ 3.2.
+
+ Other issues in the test suite have been addressed.
+
+ Nul 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.
+
+* Noteworthy changes in release 2.6.4 (2012-10-23) [stable]
+
+ Bison 2.6.3's --version was incorrect. This release fixes this issue.
+
+* Noteworthy changes in release 2.6.3 (2012-10-22) [stable]
+
+** Bug fixes
+
+ Bugs and portability issues in the test suite have been fixed.
+
+ Some errors in translations have been addressed, and --help now directs
+ users to the appropriate place to report them.
+
+ Stray Info files shipped by accident are removed.
+
+ Incorrect definitions of YY_, issued by yacc.c when no parser header is
+ generated, are removed.
+
+ All the generated headers are self-contained.
+
** Header guards (yacc.c, glr.c, glr.cc)
In order to avoid collisions, the header guards are now
will use YY_CALC_LIB_PARSE_H_INCLUDED as guard.
-** Exception safety (lalr1.cc)
-
- The parse function now catches exceptions, uses the %destructors to
- release memory (the lookahead symbol and the symbols pushed on the stack)
- before rethrowing the exception.
-
- This feature is somewhat experimental. User feedback would be
- appreciated.
-
** Fix compiler warnings in the generated parser (yacc.c, glr.c)
The compilation of pure parsers (%define api.pure) can trigger GCC
"function declared 'noreturn' should not return") have also been
addressed.
-** New %define variable: api.location.type (glr.cc, lalr1.cc)
-
- The %define variable api.location.type defines the name of the type to use
- for locations. When defined, Bison no longer generates the position.hh
- and location.hh files, nor does the parser will include them: the user is
- then responsible to define her type.
-
- This can be used in programs with several parsers to factor their location
- and position files: let one of them generate them, and the others just use
- them.
-
- This feature was actually introduced, but not documented, in Bison 2.5,
- under the name "location_type" (which is maintained for backward
- compatibility).
-
* Noteworthy changes in release 2.6.2 (2012-08-03) [stable]
** Bug fixes
* Noteworthy changes in release 2.6 (2012-07-19) [stable]
-** Future changes:
+** Future changes
The next major release of Bison will drop support for the following
deprecated features. Please report disagreements to bug-bison@gnu.org.
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
+ LocalWords: TOK calc yyo fval Wconflicts
Local Variables:
mode: outline