X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/77714df234fec3610f18f873b569354599fac17d..db2cc12fd07acb54b19cf6475f6d330a8b904e0a:/NEWS

diff --git a/NEWS b/NEWS
index 50fb91ef..51836800 100644
--- a/NEWS
+++ b/NEWS
@@ -1,7 +1,20 @@
 Bison News
 ----------
 
-Changes in version 1.49b:
+Changes in version 1.49b, 2002-08-12:
+
+* GLR parsing
+  The declaration
+     %glr-parser
+  causes Bison to produce a Generalized LR (GLR) parser, capable of handling
+  almost any context-free grammar, ambiguous or not.  The new declarations
+  %dprec and %merge on grammar rules allow parse-time resolution of
+  ambiguities.  Contributed by Paul Hilfinger.
+
+* Output Directory
+  When not in Yacc compatibility mode, when the output file was not
+  specified, runnning `bison foo/bar.y' created `foo/bar.c'.  It
+  now creates `bar.c'.
 
 * Undefined token
   The undefined token was systematically mapped to 2 which prevented
@@ -17,9 +30,30 @@ Changes in version 1.49b:
   user specified that one of her tokens is numbered 256, then error
   will be mapped onto another number.
 
-* Large grammars
-  Large grammars are now supported (large token numbers, large grammar
-  size (= sum of the LHS and RHS lengths), large LALR tables).
+* Verbose error messages
+  They no longer report `..., expecting error or...' for state where
+  error recovery is possible.
+
+* End token
+  Defaults to `$end' instead of `$'.
+
+* Error recovery now conforms to documentation and to POSIX
+  When a Bison-generated parser encounters a syntax error, it now pops
+  the stack until it finds a state that allows shifting the error
+  token.  Formerly, it popped the stack until it found a state that
+  allowed some non-error action other than a default reduction on the
+  error token.  The new behavior has long been the documented behavior,
+  and has long been required by POSIX.  For more details, please see
+  <http://mail.gnu.org/pipermail/bug-bison/2002-May/001452.html>.
+
+* Traces
+  Popped tokens and nonterminals are now reported.
+
+* Larger grammars
+  Larger grammars are now supported (larger token numbers, larger grammar
+  size (= sum of the LHS and RHS lengths), larger LALR tables).
+  Formerly, many of these numbers ran afoul of 16-bit limits;
+  now these limits are 32 bits on most hosts.
 
 * Explicit initial rule
   Bison used to play hacks with the initial rule, which the user does
@@ -30,6 +64,13 @@ Changes in version 1.49b:
   Before, Bison reported the useless rules, but, although not used,
   included them in the parsers.  They are now actually removed.
 
+* Useless rules, useless nonterminals
+  They are now reported, as a warning, with their locations.
+
+* Rules never reduced
+  Rules that can never be reduced because of conflicts are now
+  reported.
+
 * Incorrect `Token not used'
   On a grammar such as
 
@@ -52,7 +93,7 @@ Changes in version 1.49b:
 * Token end-of-file
   The token end of file may be specified by the user, in which case,
   the user symbol is used in the reports, the graphs, and the verbose
-  error messages instead of `$', which remains being the defaults.
+  error messages instead of `$end', which remains being the default.
   For instance
      %token YYEOF 0
   or
@@ -62,6 +103,7 @@ Changes in version 1.49b:
   This old option, which has been broken for ages, is removed.
 
 * New translations
+  Brazilian Portuguese, thanks to Alexandre Folle de Menezes.
   Croatian, thanks to Denis Lackovic.
 
 * Incorrect token definitions
@@ -72,6 +114,29 @@ Changes in version 1.49b:
   the compiler supports ANSI C or is a C++ compiler, as enums.
   This helps debuggers producing symbols instead of values.
 
+* Reports
+  In addition to --verbose, bison supports --report=THINGS, which
+  produces additional information:
+  - itemset
+    complete the core item sets with their closure
+  - lookahead
+    explicitly associate lookaheads to items
+  - solved
+    describe shift/reduce conflicts solving.
+    Bison used to systematically output this information on top of
+    the report.  Solved conflicts are now attached to their states.
+
+* Type clashes
+  Previous versions don't complain when there is a type clash on
+  the default action if the rule has a mid-rule action, such as in:
+
+      %type <foo> bar
+      %%
+      bar: '0' {} '0';
+
+  This is fixed.
+
+* GNU M4 is now required when using Bison.
 
 Changes in version 1.35, 2002-03-25: