maint: update for changes to gnulib's announce-gen.

[bison.git] / NEWS

diff --git a/NEWS b/NEWS
index 492aa87672ce6d1aec4c1db521d01f2deab57d9c..08b0f194c7dc4a0f444cb78d284ae44ca6316830 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -119,6 +119,23 @@ Bison News
   POSIX Yacc whose use is reported by -Wyacc, and rejected in Yacc
   mode (--yacc).
 
+** YYFAIL now produces warnings and Java parsers no longer implement it.
+
+  YYFAIL has existed for many years as an undocumented feature of
+  deterministic parsers in C generated by Bison.  More recently, it was
+  a documented feature of Bison's experimental Java parsers.  As
+  promised in Bison 2.4.2's NEWS entry, any appearance of YYFAIL in a
+  semantic action now produces a deprecation warning, and Java parsers
+  no longer implement YYFAIL at all.  For further details, including a
+  discussion of how to suppress C preprocessor warnings about YYFAIL
+  being unused, see the Bison 2.4.2 NEWS entry.
+
+** `%prec IDENTIFIER' requires IDENTIFIER to be defined separately.
+
+  As promised in Bison 2.4.2's NEWS entry, it is now an error if a token
+  that appears after a %prec directive is not defined by %token, %left,
+  %right, or %nonassoc.  This is required by POSIX.
+
 ** Temporary hack for adding a semicolon to the user action.
 
   Previously, Bison appended a semicolon to every user action for
@@ -162,7 +179,30 @@ Bison News
   were resolved with %nonassoc.  Such tokens are now properly omitted
   from the list.
 
-* Changes in version 2.4.2 (????-??-??):
+** Destructor calls fixed for lookaheads altered in semantic actions.
+
+  Previously for deterministic parsers in C, if a user semantic action
+  altered yychar, the parser in some cases used the old yychar value to
+  determine which destructor to call for the lookahead upon a syntax
+  error or upon parser return.  This bug has been fixed.
+
+* Changes in version 2.4.2 (2010-03-20):
+
+** Some portability problems that resulted in failures and livelocks
+   in the test suite on some versions of at least Solaris, AIX, HP-UX,
+   RHEL4, and Tru64 have been addressed.  As a result, fatal Bison
+   errors should no longer cause M4 to report a broken pipe on the
+   affected platforms.
+
+** `%prec IDENTIFIER' requires IDENTIFIER to be defined separately.
+
+  POSIX specifies that an error be reported for any identifier that does
+  not appear on the LHS of a grammar rule and that is not defined by
+  %token, %left, %right, or %nonassoc.  Bison 2.3b and later lost this
+  error report for the case when an identifier appears only after a
+  %prec directive.  It is now restored.  However, for backward
+  compatibility with recent Bison releases, it is only a warning for
+  now.  In Bison 2.5 and later, it will return to being an error.
 
 ** Detection of GNU M4 1.4.6 or newer during configure is improved.
 
@@ -1285,8 +1325,7 @@ End:
 
 -----
 
-Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
-2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
+Copyright (C) 1995-2010 Free Software Foundation, Inc.
 
 This file is part of Bison, the GNU Parser Generator.