java: finish fixing parser stack popping bug.

[bison.git] / NEWS

diff --git a/NEWS b/NEWS
index 061044915a9459c2347d780a5f2502e538e7c5f6..144aae850c583423d5bc718e0f46891f531e72dd 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -116,27 +116,27 @@ Bison News
     %define lr.type ielr
     %define lr.type canonical-lr
 
     %define lr.type ielr
     %define lr.type canonical-lr
 

-  The default reduction optimization in the parser tables can also be
-  adjusted using `%define lr.default-reductions'.  See the documentation
-  for `%define lr.type' and `%define lr.default-reductions' in the
-  section `Bison Declaration Summary' in the Bison manual for the
-  details.
+  The default-reduction optimization in the parser tables can also be
+  adjusted using `%define lr.default-reductions'.  For details on both
+  of these features, see the new section `Tuning LR' in the Bison
+  manual.

 
   These features are experimental.  More user feedback will help to
   stabilize them.
 
 
   These features are experimental.  More user feedback will help to
   stabilize them.
 

-** LAC (lookahead correction) for syntax error handling:
+** LAC (Lookahead Correction) for syntax error handling:

 
   Canonical LR, IELR, and LALR can suffer from a couple of problems
   upon encountering a syntax error.  First, the parser might perform
   additional parser stack reductions before discovering the syntax
 
   Canonical LR, IELR, and LALR can suffer from a couple of problems
   upon encountering a syntax error.  First, the parser might perform
   additional parser stack reductions before discovering the syntax

-  error.  Such reductions perform user semantic actions that are
+  error.  Such reductions can perform user semantic actions that are

   unexpected because they are based on an invalid token, and they
   cause error recovery to begin in a different syntactic context than
   the one in which the invalid token was encountered.  Second, when
   unexpected because they are based on an invalid token, and they
   cause error recovery to begin in a different syntactic context than
   the one in which the invalid token was encountered.  Second, when

-  verbose error messages are enabled (with %error-verbose or `#define
-  YYERROR_VERBOSE'), the expected token list in the syntax error
-  message can both contain invalid tokens and omit valid tokens.
+  verbose error messages are enabled (with %error-verbose or the
+  obsolete `#define YYERROR_VERBOSE'), the expected token list in the
+  syntax error message can both contain invalid tokens and omit valid
+  tokens.

 
   The culprits for the above problems are %nonassoc, default
   reductions in inconsistent states, and parser state merging.  Thus,
 
   The culprits for the above problems are %nonassoc, default
   reductions in inconsistent states, and parser state merging.  Thus,


@@ -144,11 +144,11 @@ Bison News
   %nonassoc is used or if default reductions are enabled for
   inconsistent states.
 
   %nonassoc is used or if default reductions are enabled for
   inconsistent states.
 

-  LAC is a new mechanism within the parsing algorithm that completely
-  solves these problems for canonical LR, IELR, and LALR without
-  sacrificing %nonassoc, default reductions, or state mering.  When
-  LAC is in use, canonical LR and IELR behave exactly the same for
-  both syntactically acceptable and syntactically unacceptable input.
+  LAC is a new mechanism within the parsing algorithm that solves
+  these problems for canonical LR, IELR, and LALR without sacrificing
+  %nonassoc, default reductions, or state merging.  When LAC is in
+  use, canonical LR and IELR behave almost exactly the same for both
+  syntactically acceptable and syntactically unacceptable input.

   While LALR still does not support the full language-recognition
   power of canonical LR and IELR, LAC at least enables LALR's syntax
   error handling to correctly reflect LALR's language-recognition
   While LALR still does not support the full language-recognition
   power of canonical LR and IELR, LAC at least enables LALR's syntax
   error handling to correctly reflect LALR's language-recognition


@@ -159,8 +159,8 @@ Bison News
 
     %define parse.lac full
 
 
     %define parse.lac full
 

-  See the documentation for `%define parse.lac' in the section `Bison
-  Declaration Summary' in the Bison manual for additional details.
+  See the new section `LAC' in the Bison manual for additional
+  details including a few caveats.

 
   LAC is an experimental feature.  More user feedback will help to
   stabilize it.
 
   LAC is an experimental feature.  More user feedback will help to
   stabilize it.


@@ -314,11 +314,11 @@ Bison News
 
 ** Verbose syntax error message fixes:
 
 
 ** Verbose syntax error message fixes:
 

-  When %error-verbose or `#define YYERROR_VERBOSE' is specified,
-  syntax error messages produced by the generated parser include the
-  unexpected token as well as a list of expected tokens.  The effect
-  of %nonassoc on these verbose messages has been corrected in two
-  ways, but a complete fix requires LAC, described above:
+  When %error-verbose or the obsolete `#define YYERROR_VERBOSE' is
+  specified, syntax error messages produced by the generated parser
+  include the unexpected token as well as a list of expected tokens.
+  The effect of %nonassoc on these verbose messages has been corrected
+  in two ways, but a more complete fix requires LAC, described above:

 
 *** When %nonassoc is used, there can exist parser states that accept no
     tokens, and so the parser does not always require a lookahead token
 
 *** When %nonassoc is used, there can exist parser states that accept no
     tokens, and so the parser does not always require a lookahead token


@@ -350,6 +350,13 @@ Bison News
     canonical LR.  However, LAC is still experimental and is disabled
     by default.
 
     canonical LR.  However, LAC is still experimental and is disabled
     by default.
 

+** Java skeleton fixes:
+
+*** A location handling bug has been fixed.
+
+*** The top element of each of the value stack and location stack is now
+    cleared when popped so that it can be garbage collected.
+

 * Changes in version 2.4.3 (2010-08-05):
 
 ** Bison now obeys -Werror and --warnings=error for warnings about
 * Changes in version 2.4.3 (2010-08-05):
 
 ** Bison now obeys -Werror and --warnings=error for warnings about