version 2.7.1

[bison.git] / NEWS

diff --git a/NEWS b/NEWS
index 1fe419f426ca4e42683440c9c8a04065788b03f8..d445ce7e2dd877b6a28ff9e12e2260dd323ac9ef 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -1,53 +1,185 @@
 GNU Bison NEWS
 
 GNU Bison NEWS
 

-* Noteworthy changes in release ?.? (????-??-??) [?]
+* Noteworthy changes in release 2.7.1 (2013-04-15) [stable]

 
 ** Bug fixes
 
 
 ** Bug fixes
 

-  Bugs and portability issues in the test suite have been fixed.
+*** Fix compiler attribute portability (yacc.c)

 
 

-  Some errors in translations have been addressed, and --help now directs
-  users to the appropriate place to report them.
+  With locations enabled, __attribute__ was used unprotected.

 
 

-  Stray Info files shipped by accident are removed.
+*** Fix some compiler warnings (lalr1.cc)

 
 

-  Incorrect definitions of YY_, issued by yacc.c when no parser header is
-  generated, are removed.
+* Noteworthy changes in release 2.7 (2012-12-12) [stable]

 
 

-  All the generated headers are self-contained.
+** Bug fixes
+
+  Warnings about uninitialized yylloc in yyparse have been fixed.

 
 

-** Changes in the format of error messages
+  Restored C90 compliance (yet no report was ever made).
+
+** Diagnostics are improved
+
+*** Changes in the format of error messages

 
   This used to be the format of many error reports:
 
 
   This used to be the format of many error reports:
 

-    foo.y:5.10-24: result type clash on merge function 'merge': <t3> != <t2>
-    foo.y:4.13-27: previous declaration
+    input.y:2.7-12: %type redeclaration for exp
+    input.y:1.7-12: previous declaration

 
   It is now:
 
 
   It is now:
 

-    foo.y:5.10-25: result type clash on merge function 'merge': <t3> != <t2>
-    foo.y:4.13-27:     previous declaration
+    input.y:2.7-12: error: %type redeclaration for exp
+    input.y:1.7-12:     previous declaration

 
 

-** Header guards (yacc.c, glr.c, glr.cc)
+*** New format for error reports: carets

 
 

-  In order to avoid collisions, the header guards are now
-  YY_<PREFIX>_<FILE>_INCLUDED, instead of merely <PREFIX>_<FILE>.
-  For instance the header generated from
+  Caret errors have been added to Bison:

 
 

-    %define api.prefix "calc"
-    %defines "lib/parse.h"
+    input.y:2.7-12: error: %type redeclaration for exp
+     %type <sval> exp
+           ^^^^^^
+    input.y:1.7-12:     previous declaration
+     %type <ival> exp
+           ^^^^^^

 
 

-  will use YY_CALC_LIB_PARSE_H_INCLUDED as guard.
+  or
+
+    input.y:3.20-23: error: ambiguous reference: '$exp'
+     exp: exp '+' exp { $exp = $1 + $3; };
+                        ^^^^
+    input.y:3.1-3:       refers to: $exp at $$
+     exp: exp '+' exp { $exp = $1 + $3; };
+     ^^^
+    input.y:3.6-8:       refers to: $exp at $1
+     exp: exp '+' exp { $exp = $1 + $3; };
+          ^^^
+    input.y:3.14-16:     refers to: $exp at $3
+     exp: exp '+' exp { $exp = $1 + $3; };
+                  ^^^
+
+  The default behaviour for now is still not to display these unless
+  explictly asked with -fcaret (or -fall). However, in a later release, it
+  will be made the default behavior (but may still be deactivated with
+  -fno-caret).
+
+** New value for %define variable: api.pure full
+
+  The %define variable api.pure requests a pure (reentrant) parser. However,
+  for historical reasons, using it in a location-tracking Yacc parser
+  resulted in a 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).
+
+  The use of "%define api.pure true" is deprecated in favor of this new
+  "%define api.pure full".
+
+** 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.

 
 ** 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)
 
 ** 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.
+  before re-throwing the exception.

 
   This feature is somewhat experimental.  User feedback would be
   appreciated.
 
 
   This feature is somewhat experimental.  User feedback would be
   appreciated.
 

+** 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.
+
+** %language is no longer an experimental feature.
+
+  The introduction of this feature, in 2.4, was four years ago. The
+  --language option and the %language directive are no longer experimental.
+
+** Documentation
+
+  The sections about shift/reduce and reduce/reduce conflicts resolution
+  have been fixed and extended.
+
+  Although introduced more than four years ago, XML and Graphviz reports
+  were not properly documented.
+
+  The translation of mid-rule actions is now described.
+
+* 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
+  YY_<PREFIX>_<FILE>_INCLUDED, instead of merely <PREFIX>_<FILE>.
+  For instance the header generated from
+
+    %define api.prefix "calc"
+    %defines "lib/parse.h"
+
+  will use YY_CALC_LIB_PARSE_H_INCLUDED as guard.
+

 ** Fix compiler warnings in the generated parser (yacc.c, glr.c)
 
   The compilation of pure parsers (%define api.pure) can trigger GCC
 ** Fix compiler warnings in the generated parser (yacc.c, glr.c)
 
   The compilation of pure parsers (%define api.pure) can trigger GCC


@@ -383,6 +515,7 @@ GNU Bison NEWS
 
   These features are experimental in this version.  More user feedback
   will help to stabilize them.
 
   These features are experimental in this version.  More user feedback
   will help to stabilize them.

+  Contributed by Alex Rozenman.

 
 ** IELR(1) and canonical LR(1):
 
 
 ** IELR(1) and canonical LR(1):
 


@@ -899,6 +1032,7 @@ GNU Bison NEWS
 
   The current Java interface is experimental and may evolve.  More user
   feedback will help to stabilize it.
 
   The current Java interface is experimental and may evolve.  More user
   feedback will help to stabilize it.

+  Contributed by Paolo Bonzini.

 
 ** %language
 
 
 ** %language
 


@@ -912,6 +1046,7 @@ GNU Bison NEWS
   Bison can now generate an XML report of the LALR(1) automaton using the new
   "--xml" option.  The current XML schema is experimental and may evolve.  More
   user feedback will help to stabilize it.
   Bison can now generate an XML report of the LALR(1) automaton using the new
   "--xml" option.  The current XML schema is experimental and may evolve.  More
   user feedback will help to stabilize it.

+  Contributed by Wojciech Polak.

 
 ** The grammar file may now specify the name of the parser header file using
   %defines.  For example:
 
 ** The grammar file may now specify the name of the parser header file using
   %defines.  For example:


@@ -1888,7 +2023,7 @@ Output file does not redefine const for C++.
 
 -----
 
 
 -----
 

-Copyright (C) 1995-2012 Free Software Foundation, Inc.
+Copyright (C) 1995-2013 Free Software Foundation, Inc.

 
 This file is part of Bison, the GNU Parser Generator.
 
 
 This file is part of Bison, the GNU Parser Generator.
 


@@ -1922,7 +2057,8 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
  LocalWords:  namespaces strerror const autoconfiguration Dconst Autoconf's FDL
  LocalWords:  Automake TMPDIR LESSEQ ylwrap endif yydebug YYTOKEN YYLSP ival hh
  LocalWords:  extern YYTOKENTYPE TOKENTYPE yytokentype tokentype STYPE lval pdf
  LocalWords:  namespaces strerror const autoconfiguration Dconst Autoconf's FDL
  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 calc yyo fval
+ LocalWords:  lang yyoutput dvi html ps POSIX lvalp llocp calc yyo fval Wmaybe
+ LocalWords:  yyvsp pragmas noreturn java's

 
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