* NEWS: Use more outline-mode markup.
Suggested by Jim Meyering.
+2008-11-04 Akim Demaille <demaille@gostai.com>
+
+ Reformat NEWS.
+ * NEWS: Use more outline-mode markup.
+ Suggested by Jim Meyering.
+
2008-11-04 Joel E. Denny <jdenny@ces.clemson.edu>
Fix user actions without a trailing semicolon.
2008-11-04 Joel E. Denny <jdenny@ces.clemson.edu>
Fix user actions without a trailing semicolon.
-Changes in version ?.? (????-??-??):
+* Changes in version ?.? (????-??-??):
-Changes in version 2.4 (2008-11-02):
+* Changes in version 2.4 (2008-11-02):
-* %language is an experimental feature.
+** %language is an experimental feature.
We first introduced this feature in test release 2.3b as a cleaner
alternative to %skeleton. Since then, we have discussed the possibility of
We first introduced this feature in test release 2.3b as a cleaner
alternative to %skeleton. Since then, we have discussed the possibility of
we consider %language to be an experimental feature that will likely evolve
in future releases.
we consider %language to be an experimental feature that will likely evolve
in future releases.
-* Forward compatibility with GNU M4 has been improved.
+** Forward compatibility with GNU M4 has been improved.
-* Several bugs in the C++ skeleton and the experimental Java skeleton have been
+** Several bugs in the C++ skeleton and the experimental Java skeleton have been
-Changes in version 2.3b (2008-05-27):
+* Changes in version 2.3b (2008-05-27):
-* The quotes around NAME that used to be required in the following directive
+** The quotes around NAME that used to be required in the following directive
are now deprecated:
%define NAME "VALUE"
are now deprecated:
%define NAME "VALUE"
-* The directive `%pure-parser' is now deprecated in favor of:
+** The directive `%pure-parser' is now deprecated in favor of:
%define api.pure
which has the same effect except that Bison is more careful to warn about
unreasonable usage in the latter case.
%define api.pure
which has the same effect except that Bison is more careful to warn about
unreasonable usage in the latter case.
Bison can now generate an LALR(1) parser in C with a push interface. That
is, instead of invoking `yyparse', which pulls tokens from `yylex', you can
Bison can now generate an LALR(1) parser in C with a push interface. That
is, instead of invoking `yyparse', which pulls tokens from `yylex', you can
The current push parsing interface is experimental and may evolve. More user
feedback will help to stabilize it.
The current push parsing interface is experimental and may evolve. More user
feedback will help to stabilize it.
-* The -g and --graph options now output graphs in Graphviz DOT format,
+** The -g and --graph options now output graphs in Graphviz DOT format,
not VCG format. Like --graph, -g now also takes an optional FILE argument
and thus cannot be bundled with other short options.
not VCG format. Like --graph, -g now also takes an optional FILE argument
and thus cannot be bundled with other short options.
Bison can now generate an LALR(1) parser in Java. The skeleton is
`data/lalr1.java'. Consider using the new %language directive instead of
Bison can now generate an LALR(1) parser in Java. The skeleton is
`data/lalr1.java'. Consider using the new %language directive instead of
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.
This new directive specifies the programming language of the generated
parser, which can be C (the default), C++, or Java. Besides the skeleton
that Bison uses, the directive affects the names of the generated files if
the grammar file's name ends in ".y".
This new directive specifies the programming language of the generated
parser, which can be C (the default), C++, or Java. Besides the skeleton
that Bison uses, the directive affects the names of the generated files if
the grammar file's name ends in ".y".
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.
-* The grammar file may now specify the name of the parser header file using
+** The grammar file may now specify the name of the parser header file using
%defines. For example:
%defines "parser.h"
%defines. For example:
%defines "parser.h"
-* When reporting useless rules, useless nonterminals, and unused terminals,
+** When reporting useless rules, useless nonterminals, and unused terminals,
Bison now employs the terms "useless in grammar" instead of "useless",
"useless in parser" instead of "never reduced", and "unused in grammar"
instead of "unused".
Bison now employs the terms "useless in grammar" instead of "useless",
"useless in parser" instead of "never reduced", and "unused in grammar"
instead of "unused".
-* Unreachable State Removal
+** Unreachable State Removal
Previously, Bison sometimes generated parser tables containing unreachable
states. A state can become unreachable during conflict resolution if Bison
Previously, Bison sometimes generated parser tables containing unreachable
states. A state can become unreachable during conflict resolution if Bison
See the %define entry in the `Bison Declaration Summary' in the Bison manual
for further discussion.
See the %define entry in the `Bison Declaration Summary' in the Bison manual
for further discussion.
-* Lookahead Set Correction in the `.output' Report
+** Lookahead Set Correction in the `.output' Report
When instructed to generate a `.output' file including lookahead sets
(using `--report=lookahead', for example), Bison now prints each reduction's
When instructed to generate a `.output' file including lookahead sets
(using `--report=lookahead', for example), Bison now prints each reduction's
bug affected only the `.output' file and not the generated parser source
code.
bug affected only the `.output' file and not the generated parser source
code.
-* --report-file=FILE is a new option to override the default `.output' file
+** --report-file=FILE is a new option to override the default `.output' file
-* The `=' that used to be required in the following directives is now
+** The `=' that used to be required in the following directives is now
deprecated:
%file-prefix "parser"
%name-prefix "c_"
%output "parser.c"
deprecated:
%file-prefix "parser"
%name-prefix "c_"
%output "parser.c"
-* An Alternative to `%{...%}' -- `%code QUALIFIER {CODE}'
+** An Alternative to `%{...%}' -- `%code QUALIFIER {CODE}'
Bison 2.3a provided a new set of directives as a more flexible alternative to
the traditional Yacc prologue blocks. Those have now been consolidated into
Bison 2.3a provided a new set of directives as a more flexible alternative to
the traditional Yacc prologue blocks. Those have now been consolidated into
The prologue alternatives are experimental. More user feedback will help to
determine whether they should become permanent features.
The prologue alternatives are experimental. More user feedback will help to
determine whether they should become permanent features.
-* Revised warning: unset or unused mid-rule values
+** Revised warning: unset or unused mid-rule values
Since Bison 2.2, Bison has warned about mid-rule values that are set but not
used within any of the actions of the parent rule. For example, Bison warns
Since Bison 2.2, Bison has warned about mid-rule values that are set but not
used within any of the actions of the parent rule. For example, Bison warns
To enable these warnings, specify the option `--warnings=midrule-values' or
`-W', which is a synonym for `--warnings=all'.
To enable these warnings, specify the option `--warnings=midrule-values' or
`-W', which is a synonym for `--warnings=all'.
-* Default %destructor or %printer with `<*>' or `<>'
+** Default %destructor or %printer with `<*>' or `<>'
Bison now recognizes two separate kinds of default %destructor's and
%printer's:
Bison now recognizes two separate kinds of default %destructor's and
%printer's:
See the section `Freeing Discarded Symbols' in the Bison manual for further
details.
See the section `Freeing Discarded Symbols' in the Bison manual for further
details.
-* %left, %right, and %nonassoc can now declare token numbers. This is required
+** %left, %right, and %nonassoc can now declare token numbers. This is required
by POSIX. However, see the end of section `Operator Precedence' in the Bison
manual for a caveat concerning the treatment of literal strings.
by POSIX. However, see the end of section `Operator Precedence' in the Bison
manual for a caveat concerning the treatment of literal strings.
-* The nonfunctional --no-parser, -n, and %no-parser options have been
+** The nonfunctional --no-parser, -n, and %no-parser options have been
completely removed from Bison.
completely removed from Bison.
-Changes in version 2.3a, 2006-09-13:
+* Changes in version 2.3a, 2006-09-13:
-* Instead of %union, you can define and use your own union type
+** Instead of %union, you can define and use your own union type
YYSTYPE if your grammar contains at least one <type> tag.
Your YYSTYPE need not be a macro; it can be a typedef.
This change is for compatibility with other Yacc implementations,
and is required by POSIX.
YYSTYPE if your grammar contains at least one <type> tag.
Your YYSTYPE need not be a macro; it can be a typedef.
This change is for compatibility with other Yacc implementations,
and is required by POSIX.
-* Locations columns and lines start at 1.
+** Locations columns and lines start at 1.
In accordance with the GNU Coding Standards and Emacs.
In accordance with the GNU Coding Standards and Emacs.
-* You may now declare per-type and default %destructor's and %printer's:
+** You may now declare per-type and default %destructor's and %printer's:
%destructor's and %printer's were experimental, and they were rewritten in
future versions.]
%destructor's and %printer's were experimental, and they were rewritten in
future versions.]
-* Except for LALR(1) parsers in C with POSIX Yacc emulation enabled (with `-y',
+** Except for LALR(1) parsers in C with POSIX Yacc emulation enabled (with `-y',
`--yacc', or `%yacc'), Bison no longer generates #define statements for
associating token numbers with token names. Removing the #define statements
helps to sanitize the global namespace during preprocessing, but POSIX Yacc
requires them. Bison still generates an enum for token names in all cases.
`--yacc', or `%yacc'), Bison no longer generates #define statements for
associating token numbers with token names. Removing the #define statements
helps to sanitize the global namespace during preprocessing, but POSIX Yacc
requires them. Bison still generates an enum for token names in all cases.
-* Handling of traditional Yacc prologue blocks is now more consistent but
+** Handling of traditional Yacc prologue blocks is now more consistent but
potentially incompatible with previous releases of Bison.
As before, you declare prologue blocks in your grammar file with the
potentially incompatible with previous releases of Bison.
As before, you declare prologue blocks in your grammar file with the
Now, Bison never inserts the pre-prologue into the header file. In the code
file, it always inserts it before the token definitions.
Now, Bison never inserts the pre-prologue into the header file. In the code
file, it always inserts it before the token definitions.
-* Bison now provides a more flexible alternative to the traditional Yacc
+** Bison now provides a more flexible alternative to the traditional Yacc
prologue blocks: %before-header, %start-header, %end-header, and
%after-header.
prologue blocks: %before-header, %start-header, %end-header, and
%after-header.
[Although we failed to mention this here in the 2.3a release, the prologue
alternatives were experimental, and they were rewritten in future versions.]
[Although we failed to mention this here in the 2.3a release, the prologue
alternatives were experimental, and they were rewritten in future versions.]
-* The option `--report=look-ahead' has been changed to `--report=lookahead'.
+** The option `--report=look-ahead' has been changed to `--report=lookahead'.
The old spelling still works, but is not documented and may be removed
in a future release.
The old spelling still works, but is not documented and may be removed
in a future release.
-Changes in version 2.3, 2006-06-05:
+* Changes in version 2.3, 2006-06-05:
-* GLR grammars should now use `YYRECOVERING ()' instead of `YYRECOVERING',
+** GLR grammars should now use `YYRECOVERING ()' instead of `YYRECOVERING',
for compatibility with LALR(1) grammars.
for compatibility with LALR(1) grammars.
-* It is now documented that any definition of YYSTYPE or YYLTYPE should
+** It is now documented that any definition of YYSTYPE or YYLTYPE should
be to a type name that does not contain parentheses or brackets.
be to a type name that does not contain parentheses or brackets.
-Changes in version 2.2, 2006-05-19:
+* Changes in version 2.2, 2006-05-19:
-* The distribution terms for all Bison-generated parsers now permit
+** The distribution terms for all Bison-generated parsers now permit
using the parsers in nonfree programs. Previously, this permission
was granted only for Bison-generated LALR(1) parsers in C.
using the parsers in nonfree programs. Previously, this permission
was granted only for Bison-generated LALR(1) parsers in C.
-* %name-prefix changes the namespace name in C++ outputs.
+** %name-prefix changes the namespace name in C++ outputs.
-* The C++ parsers export their token_type.
+** The C++ parsers export their token_type.
-* Bison now allows multiple %union declarations, and concatenates
+** Bison now allows multiple %union declarations, and concatenates
-* New warning: unused values
+** New warning: unused values
Right-hand side symbols whose values are not used are reported,
if the symbols have destructors. For instance:
Right-hand side symbols whose values are not used are reported,
if the symbols have destructors. For instance:
The warning is intended to help catching lost values and memory leaks.
If a value is ignored, its associated memory typically is not reclaimed.
The warning is intended to help catching lost values and memory leaks.
If a value is ignored, its associated memory typically is not reclaimed.
-* %destructor vs. YYABORT, YYACCEPT, and YYERROR.
+** %destructor vs. YYABORT, YYACCEPT, and YYERROR.
Destructors are now called when user code invokes YYABORT, YYACCEPT,
and YYERROR, for all objects on the stack, other than objects
corresponding to the right-hand side of the current rule.
Destructors are now called when user code invokes YYABORT, YYACCEPT,
and YYERROR, for all objects on the stack, other than objects
corresponding to the right-hand side of the current rule.
Incorrect numbers of expected conflicts are now actual errors,
instead of warnings.
Incorrect numbers of expected conflicts are now actual errors,
instead of warnings.
The %parse-params are available in the destructors (and the
experimental printers) as per the documentation.
The %parse-params are available in the destructors (and the
experimental printers) as per the documentation.
-* Bison now warns if it finds a stray `$' or `@' in an action.
+** Bison now warns if it finds a stray `$' or `@' in an action.
This specifies that the grammar file depends on features implemented
in Bison version VERSION or higher.
This specifies that the grammar file depends on features implemented
in Bison version VERSION or higher.
-* lalr1.cc: The token and value types are now class members.
+** lalr1.cc: The token and value types are now class members.
The tokens were defined as free form enums and cpp macros. YYSTYPE
was defined as a free form union. They are now class members:
tokens are enumerations of the `yy::parser::token' struct, and the
The tokens were defined as free form enums and cpp macros. YYSTYPE
was defined as a free form union. They are now class members:
tokens are enumerations of the `yy::parser::token' struct, and the
If you wish to update, then make sure older version of Bison will
fail using `%require "2.2"'.
If you wish to update, then make sure older version of Bison will
fail using `%require "2.2"'.
-Changes in version 2.1, 2005-09-16:
+* Changes in version 2.1, 2005-09-16:
-* The C++ lalr1.cc skeleton supports %lex-param.
+** The C++ lalr1.cc skeleton supports %lex-param.
-* Bison-generated parsers now support the translation of diagnostics like
+** Bison-generated parsers now support the translation of diagnostics like
"syntax error" into languages other than English. The default
language is still English. For details, please see the new
Internationalization section of the Bison manual. Software
distributors should also see the new PACKAGING file. Thanks to
Bruno Haible for this new feature.
"syntax error" into languages other than English. The default
language is still English. For details, please see the new
Internationalization section of the Bison manual. Software
distributors should also see the new PACKAGING file. Thanks to
Bruno Haible for this new feature.
-* Wording in the Bison-generated parsers has been changed slightly to
+** Wording in the Bison-generated parsers has been changed slightly to
simplify translation. In particular, the message "memory exhausted"
has replaced "parser stack overflow", as the old message was not
always accurate for modern Bison-generated parsers.
simplify translation. In particular, the message "memory exhausted"
has replaced "parser stack overflow", as the old message was not
always accurate for modern Bison-generated parsers.
-* Destructors are now called when the parser aborts, for all symbols left
+** Destructors are now called when the parser aborts, for all symbols left
behind on the stack. Also, the start symbol is now destroyed after a
successful parse. In both cases, the behavior was formerly inconsistent.
behind on the stack. Also, the start symbol is now destroyed after a
successful parse. In both cases, the behavior was formerly inconsistent.
-* When generating verbose diagnostics, Bison-generated parsers no longer
+** When generating verbose diagnostics, Bison-generated parsers no longer
quote the literal strings associated with tokens. For example, for
a syntax error associated with '%token NUM "number"' they might
print 'syntax error, unexpected number' instead of 'syntax error,
unexpected "number"'.
\f
quote the literal strings associated with tokens. For example, for
a syntax error associated with '%token NUM "number"' they might
print 'syntax error, unexpected number' instead of 'syntax error,
unexpected "number"'.
\f
-Changes in version 2.0, 2004-12-25:
+* Changes in version 2.0, 2004-12-25:
-* Possibly-incompatible changes
+** Possibly-incompatible changes
- Bison-generated parsers no longer default to using the alloca function
(when available) to extend the parser stack, due to widespread
- Bison-generated parsers no longer default to using the alloca function
(when available) to extend the parser stack, due to widespread
- NUL bytes are no longer allowed in Bison string literals, unfortunately.
- NUL bytes are no longer allowed in Bison string literals, unfortunately.
- GLR grammars now support locations.
- GLR grammars now support locations.
- New configure option --disable-yacc, to disable installation of the
yacc command and -ly library introduced in 1.875 for POSIX conformance.
- New configure option --disable-yacc, to disable installation of the
yacc command and -ly library introduced in 1.875 for POSIX conformance.
- For now, %expect-count violations are now just warnings, not errors.
This is for compatibility with Bison 1.75 and earlier (when there are
- For now, %expect-count violations are now just warnings, not errors.
This is for compatibility with Bison 1.75 and earlier (when there are
- Semicolons are now allowed before "|" in grammar rules, as POSIX requires.
\f
- Semicolons are now allowed before "|" in grammar rules, as POSIX requires.
\f
-Changes in version 1.875, 2003-01-01:
+* Changes in version 1.875, 2003-01-01:
-* The documentation license has been upgraded to version 1.2
+** The documentation license has been upgraded to version 1.2
of the GNU Free Documentation License.
of the GNU Free Documentation License.
-* syntax error processing
+** syntax error processing
- In Yacc-style parsers YYLLOC_DEFAULT is now used to compute error
locations too. This fixes bugs in error-location computation.
- In Yacc-style parsers YYLLOC_DEFAULT is now used to compute error
locations too. This fixes bugs in error-location computation.
- #defining yyerror to steal internal variables is discouraged.
It is not guaranteed to work forever.
- #defining yyerror to steal internal variables is discouraged.
It is not guaranteed to work forever.
- Semicolons are once again optional at the end of grammar rules.
This reverts to the behavior of Bison 1.33 and earlier, and improves
- Semicolons are once again optional at the end of grammar rules.
This reverts to the behavior of Bison 1.33 and earlier, and improves
using typedef instead of defining it as a macro.
For consistency, YYLTYPE is also declared instead of defined.
using typedef instead of defining it as a macro.
For consistency, YYLTYPE is also declared instead of defined.
-* Other compatibility issues
+** Other compatibility issues
- %union directives can now have a tag before the `{', e.g., the
directive `%union foo {...}' now generates the C code
- %union directives can now have a tag before the `{', e.g., the
directive `%union foo {...}' now generates the C code
typedefs or tags; they are no longer documented and are planned to be
withdrawn in a future release.
typedefs or tags; they are no longer documented and are planned to be
withdrawn in a future release.
- GLR and inline
Users of Bison have to decide how they handle the portability of the
- GLR and inline
Users of Bison have to decide how they handle the portability of the
- `parsing stack overflow...' -> `parser stack overflow'
GLR parsers now report `parser stack overflow' as per the Bison manual.
- `parsing stack overflow...' -> `parser stack overflow'
GLR parsers now report `parser stack overflow' as per the Bison manual.
-* Bison now warns if it detects conflicting outputs to the same file,
+** Bison now warns if it detects conflicting outputs to the same file,
e.g., it generates a warning for `bison -d -o foo.h foo.y' since
that command outputs both code and header to foo.h.
e.g., it generates a warning for `bison -d -o foo.h foo.y' since
that command outputs both code and header to foo.h.
+** #line in output files
- --no-line works properly.
- --no-line works properly.
-* Bison can no longer be built by a K&R C compiler; it requires C89 or
+** Bison can no longer be built by a K&R C compiler; it requires C89 or
later to be built. This change originally took place a few versions
ago, but nobody noticed until we recently asked someone to try
building Bison with a K&R C compiler.
\f
later to be built. This change originally took place a few versions
ago, but nobody noticed until we recently asked someone to try
building Bison with a K&R C compiler.
\f
-Changes in version 1.75, 2002-10-14:
+* Changes in version 1.75, 2002-10-14:
-* Bison should now work on 64-bit hosts.
+** Bison should now work on 64-bit hosts.
-* Indonesian translation thanks to Tedi Heriyanto.
+** Indonesian translation thanks to Tedi Heriyanto.
Fix spurious parse errors.
Fix spurious parse errors.
Some people redefine yyerror to steal yyparse' private variables.
Reenable this trick until an official feature replaces it.
Some people redefine yyerror to steal yyparse' private variables.
Reenable this trick until an official feature replaces it.
In agreement with POSIX and with other Yaccs, leaving a default
action is valid when $$ is untyped, and $1 typed:
In agreement with POSIX and with other Yaccs, leaving a default
action is valid when $$ is untyped, and $1 typed:
-* Values of mid-rule actions
+** Values of mid-rule actions
The following code:
foo: { ... } { $$ = $1; } ...
The following code:
foo: { ... } { $$ = $1; } ...
was incorrectly rejected: $1 is defined in the second mid-rule
action, and is equal to the $$ of the first mid-rule action.
\f
was incorrectly rejected: $1 is defined in the second mid-rule
action, and is equal to the $$ of the first mid-rule action.
\f
-Changes in version 1.50, 2002-10-04:
+* Changes in version 1.50, 2002-10-04:
The declaration
%glr-parser
causes Bison to produce a Generalized LR (GLR) parser, capable of handling
The declaration
%glr-parser
causes Bison to produce a Generalized LR (GLR) parser, capable of handling
Unfortunately Bison 1.50 does not work properly on 64-bit hosts
like the Alpha, so please stick to 32-bit hosts for now.
Unfortunately Bison 1.50 does not work properly on 64-bit hosts
like the Alpha, so please stick to 32-bit hosts for now.
When not in Yacc compatibility mode, when the output file was not
specified, running `bison foo/bar.y' created `foo/bar.c'. It
now creates `bar.c'.
When not in Yacc compatibility mode, when the output file was not
specified, running `bison foo/bar.y' created `foo/bar.c'. It
now creates `bar.c'.
The undefined token was systematically mapped to 2 which prevented
the use of 2 by the user. This is no longer the case.
The undefined token was systematically mapped to 2 which prevented
the use of 2 by the user. This is no longer the case.
+** Unknown token numbers
If yylex returned an out of range value, yyparse could die. This is
no longer the case.
If yylex returned an out of range value, yyparse could die. This is
no longer the case.
According to POSIX, the error token must be 256.
Bison extends this requirement by making it a preference: *if* the
user specified that one of her tokens is numbered 256, then error
will be mapped onto another number.
According to POSIX, the error token must be 256.
Bison extends this requirement by making it a preference: *if* the
user specified that one of her tokens is numbered 256, then error
will be mapped onto another number.
-* Verbose error messages
+** Verbose error messages
They no longer report `..., expecting error or...' for states where
error recovery is possible.
They no longer report `..., expecting error or...' for states where
error recovery is possible.
Defaults to `$end' instead of `$'.
Defaults to `$end' instead of `$'.
-* Error recovery now conforms to documentation and to POSIX
+** 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
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
Paul Eggert, "Reductions during Bison error handling" (2002-05-20)
<http://lists.gnu.org/archive/html/bug-bison/2002-05/msg00038.html>.
Paul Eggert, "Reductions during Bison error handling" (2002-05-20)
<http://lists.gnu.org/archive/html/bug-bison/2002-05/msg00038.html>.
Popped tokens and nonterminals are now reported.
Popped tokens and nonterminals are now reported.
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.
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
not write. It is now explicit, and visible in the reports and
graphs as rule 0.
Bison used to play hacks with the initial rule, which the user does
not write. It is now explicit, and visible in the reports and
graphs as rule 0.
Before, Bison reported the useless rules, but, although not used,
included them in the parsers. They are now actually removed.
Before, Bison reported the useless rules, but, although not used,
included them in the parsers. They are now actually removed.
-* Useless rules, useless nonterminals
+** Useless rules, useless nonterminals
They are now reported, as a warning, with their locations.
They are now reported, as a warning, with their locations.
Rules that can never be reduced because of conflicts are now
reported.
Rules that can never be reduced because of conflicts are now
reported.
-* Incorrect `Token not used'
+** Incorrect `Token not used'
On a grammar such as
%token useless useful
On a grammar such as
%token useless useful
where a token was used to set the precedence of the last rule,
bison reported both `useful' and `useless' as useless tokens.
where a token was used to set the precedence of the last rule,
bison reported both `useful' and `useless' as useless tokens.
-* Revert the C++ namespace changes introduced in 1.31
+** Revert the C++ namespace changes introduced in 1.31
as they caused too many portability hassles.
as they caused too many portability hassles.
By an accident of design, the default computation of @$ was
performed after another default computation was performed: @$ = @1.
The latter is now removed: YYLLOC_DEFAULT is fully responsible of
the computation of @$.
By an accident of design, the default computation of @$ was
performed after another default computation was performed: @$ = @1.
The latter is now removed: YYLLOC_DEFAULT is fully responsible of
the computation of @$.
The token end of file may be specified by the user, in which case,
the user symbol is used in the reports, the graphs, and the verbose
error messages instead of `$end', which remains being the default.
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 `$end', which remains being the default.
or
%token MYEOF 0 "end of file"
or
%token MYEOF 0 "end of file"
This old option, which has been broken for ages, is removed.
This old option, which has been broken for ages, is removed.
Brazilian Portuguese, thanks to Alexandre Folle de Menezes.
Croatian, thanks to Denis Lackovic.
Brazilian Portuguese, thanks to Alexandre Folle de Menezes.
Croatian, thanks to Denis Lackovic.
-* Incorrect token definitions
+** Incorrect token definitions
When given `%token 'a' "A"', Bison used to output `#define 'a' 65'.
When given `%token 'a' "A"', Bison used to output `#define 'a' 65'.
-* Token definitions as enums
+** Token definitions as enums
Tokens are output both as the traditional #define's, and, provided
the compiler supports ANSI C or is a C++ compiler, as enums.
This lets debuggers display names instead of integers.
Tokens are output both as the traditional #define's, and, provided
the compiler supports ANSI C or is a C++ compiler, as enums.
This lets debuggers display names instead of integers.
In addition to --verbose, bison supports --report=THINGS, which
produces additional information:
- itemset
In addition to --verbose, bison supports --report=THINGS, which
produces additional information:
- itemset
Bison used to systematically output this information on top of
the report. Solved conflicts are now attached to their states.
Bison used to systematically output this information on top of
the report. Solved conflicts are now attached to their states.
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:
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:
-* GNU M4 is now required when using Bison.
+** GNU M4 is now required when using Bison.
-Changes in version 1.35, 2002-03-25:
+* Changes in version 1.35, 2002-03-25:
Some projects use Bison's C parser with C++ compilers, and define
YYSTYPE as a class. The recent adjustment of C parsers for data
alignment and 64 bit architectures made this impossible.
Some projects use Bison's C parser with C++ compilers, and define
YYSTYPE as a class. The recent adjustment of C parsers for data
alignment and 64 bit architectures made this impossible.
This kludge also addresses some C++ problems when the stack was
extended.
\f
This kludge also addresses some C++ problems when the stack was
extended.
\f
-Changes in version 1.34, 2002-03-12:
+* Changes in version 1.34, 2002-03-12:
-* File name clashes are detected
+** File name clashes are detected
$ bison foo.y -d -o foo.x
fatal error: header and parser would both be named `foo.x'
$ bison foo.y -d -o foo.x
fatal error: header and parser would both be named `foo.x'
-* A missing `;' at the end of a rule triggers a warning
+** A missing `;' at the end of a rule triggers a warning
In accordance with POSIX, and in agreement with other
Yacc implementations, Bison will mandate this semicolon in the near
future. This eases the implementation of a Bison parser of Bison
grammars by making this grammar LALR(1) instead of LR(2). To
facilitate the transition, this release introduces a warning.
In accordance with POSIX, and in agreement with other
Yacc implementations, Bison will mandate this semicolon in the near
future. This eases the implementation of a Bison parser of Bison
grammars by making this grammar LALR(1) instead of LR(2). To
facilitate the transition, this release introduces a warning.
-* Revert the C++ namespace changes introduced in 1.31, as they caused too
+** Revert the C++ namespace changes introduced in 1.31, as they caused too
many portability hassles.
many portability hassles.
-* Fix test suite portability problems.
+** Fix test suite portability problems.
-Changes in version 1.33, 2002-02-07:
+* Changes in version 1.33, 2002-02-07:
Groff could not be compiled for the definition of size_t was lacking
under some conditions.
Groff could not be compiled for the definition of size_t was lacking
under some conditions.
-Changes in version 1.32, 2002-01-23:
+* Changes in version 1.32, 2002-01-23:
-* Fix Yacc output file names
+** Fix Yacc output file names
-* Italian, Dutch translations
+** Italian, Dutch translations
-Changes in version 1.31, 2002-01-14:
+* Changes in version 1.31, 2002-01-14:
-* GNU Gettext and %expect
+** GNU Gettext and %expect
GNU Gettext asserts 10 s/r conflicts, but there are 7. Now that
Bison dies on incorrect %expectations, we fear there will be
too many bug reports for Gettext, so _for the time being_, %expect
does not trigger an error when the input file is named `plural.y'.
GNU Gettext asserts 10 s/r conflicts, but there are 7. Now that
Bison dies on incorrect %expectations, we fear there will be
too many bug reports for Gettext, so _for the time being_, %expect
does not trigger an error when the input file is named `plural.y'.
-* Use of alloca in parsers
+** Use of alloca in parsers
If YYSTACK_USE_ALLOCA is defined to 0, then the parsers will use
malloc exclusively. Since 1.29, but was not NEWS'ed.
alloca is used only when compiled with GCC, to avoid portability
problems as on AIX.
If YYSTACK_USE_ALLOCA is defined to 0, then the parsers will use
malloc exclusively. Since 1.29, but was not NEWS'ed.
alloca is used only when compiled with GCC, to avoid portability
problems as on AIX.
-* yyparse now returns 2 if memory is exhausted; formerly it dumped core.
+** yyparse now returns 2 if memory is exhausted; formerly it dumped core.
-* When the generated parser lacks debugging code, YYDEBUG is now 0
+** When the generated parser lacks debugging code, YYDEBUG is now 0
(as POSIX requires) instead of being undefined.
(as POSIX requires) instead of being undefined.
Bison has always permitted actions such as { $$ = $1 }: it adds the
ending semicolon. Now if in Yacc compatibility mode, the semicolon
is no longer output: one has to write { $$ = $1; }.
Bison has always permitted actions such as { $$ = $1 }: it adds the
ending semicolon. Now if in Yacc compatibility mode, the semicolon
is no longer output: one has to write { $$ = $1; }.
+** Better C++ compliance
The output parsers try to respect C++ namespaces.
[This turned out to be a failed experiment, and it was reverted later.]
The output parsers try to respect C++ namespaces.
[This turned out to be a failed experiment, and it was reverted later.]
Fixed bugs when reporting useless nonterminals.
Fixed bugs when reporting useless nonterminals.
The parsers work properly on 64 bit hosts.
The parsers work properly on 64 bit hosts.
Some calls to strerror resulted in scrambled or missing error messages.
Some calls to strerror resulted in scrambled or missing error messages.
When the number of shift/reduce conflicts is correct, don't issue
any warning.
When the number of shift/reduce conflicts is correct, don't issue
any warning.
-* The verbose report includes the rule line numbers.
+** The verbose report includes the rule line numbers.
-* Rule line numbers are fixed in traces.
+** Rule line numbers are fixed in traces.
Verbose parse error messages from the parsers are better looking.
Before: parse error: unexpected `'/'', expecting `"number"' or `'-'' or `'(''
Now: parse error: unexpected '/', expecting "number" or '-' or '('
Verbose parse error messages from the parsers are better looking.
Before: parse error: unexpected `'/'', expecting `"number"' or `'-'' or `'(''
Now: parse error: unexpected '/', expecting "number" or '-' or '('
-* Fixed parser memory leaks.
+** Fixed parser memory leaks.
When the generated parser was using malloc to extend its stacks, the
previous allocations were not freed.
When the generated parser was using malloc to extend its stacks, the
previous allocations were not freed.
-* Fixed verbose output file.
+** Fixed verbose output file.
Some newlines were missing.
Some conflicts in state descriptions were missing.
Some newlines were missing.
Some conflicts in state descriptions were missing.
-* Fixed conflict report.
+** Fixed conflict report.
Option -v was needed to get the result.
Option -v was needed to get the result.
Was not used.
Mismatches are errors, not warnings.
Was not used.
Mismatches are errors, not warnings.
-* Fixed incorrect processing of some invalid input.
+** Fixed incorrect processing of some invalid input.
-* Fixed CPP guards: 9foo.h uses BISON_9FOO_H instead of 9FOO_H.
+** Fixed CPP guards: 9foo.h uses BISON_9FOO_H instead of 9FOO_H.
-* Fixed some typos in the documentation.
+** Fixed some typos in the documentation.
-* %token MY_EOF 0 is supported.
+** %token MY_EOF 0 is supported.
Before, MY_EOF was silently renumbered as 257.
Before, MY_EOF was silently renumbered as 257.
-* doc/refcard.tex is updated.
+** doc/refcard.tex is updated.
-* %output, %file-prefix, %name-prefix.
+** %output, %file-prefix, %name-prefix.
New, aliasing `--output-file'.
\f
New, aliasing `--output-file'.
\f
-Changes in version 1.30, 2001-10-26:
+* Changes in version 1.30, 2001-10-26:
-* `--defines' and `--graph' have now an optional argument which is the
+** `--defines' and `--graph' have now an optional argument which is the
output file name. `-d' and `-g' do not change; they do not take any
argument.
output file name. `-d' and `-g' do not change; they do not take any
argument.
-* `%source_extension' and `%header_extension' are removed, failed
+** `%source_extension' and `%header_extension' are removed, failed
-Changes in version 1.29, 2001-09-07:
+* Changes in version 1.29, 2001-09-07:
-* The output file does not define const, as this caused problems when used
+** The output file does not define const, as this caused problems when used
with common autoconfiguration schemes. If you still use ancient compilers
that lack const, compile with the equivalent of the C compiler option
`-Dconst='. autoconf's AC_C_CONST macro provides one way to do this.
with common autoconfiguration schemes. If you still use ancient compilers
that lack const, compile with the equivalent of the C compiler option
`-Dconst='. autoconf's AC_C_CONST macro provides one way to do this.
-* Added `-g' and `--graph'.
+** Added `-g' and `--graph'.
-* The Bison manual is now distributed under the terms of the GNU FDL.
+** The Bison manual is now distributed under the terms of the GNU FDL.
-* The input and the output files has automatically a similar extension.
+** The input and the output files has automatically a similar extension.
-* Russian translation added.
+** Russian translation added.
-* NLS support updated; should hopefully be less troublesome.
+** NLS support updated; should hopefully be less troublesome.
-* Added the old Bison reference card.
+** Added the old Bison reference card.
-* Added `--locations' and `%locations'.
+** Added `--locations' and `%locations'.
-* Added `-S' and `--skeleton'.
+** Added `-S' and `--skeleton'.
-* `%raw', `-r', `--raw' is disabled.
+** `%raw', `-r', `--raw' is disabled.
-* Special characters are escaped when output. This solves the problems
+** Special characters are escaped when output. This solves the problems
of the #line lines with path names including backslashes.
of the #line lines with path names including backslashes.
`%yacc', `%fixed_output_files', `%defines', `%no_parser', `%verbose',
`%debug', `%source_extension' and `%header_extension'.
`%yacc', `%fixed_output_files', `%defines', `%no_parser', `%verbose',
`%debug', `%source_extension' and `%header_extension'.
Automatic location tracking.
\f
Automatic location tracking.
\f
-Changes in version 1.28, 1999-07-06:
+* Changes in version 1.28, 1999-07-06:
-* Should compile better now with K&R compilers.
+** Should compile better now with K&R compilers.
-* Fixed a problem with escaping the double quote character.
+** Fixed a problem with escaping the double quote character.
-Changes in version 1.27:
+* Changes in version 1.27:
-* The make rule which prevented bison.simple from being created on
+** The make rule which prevented bison.simple from being created on
some systems has been fixed.
\f
some systems has been fixed.
\f
-Changes in version 1.26:
+* Changes in version 1.26:
-* Bison now uses automake.
+** Bison now uses automake.
-* New mailing lists: <bug-bison@gnu.org> and <help-bison@gnu.org>.
+** New mailing lists: <bug-bison@gnu.org> and <help-bison@gnu.org>.
-* Token numbers now start at 257 as previously documented, not 258.
+** Token numbers now start at 257 as previously documented, not 258.
-* Bison honors the TMPDIR environment variable.
+** Bison honors the TMPDIR environment variable.
-* A couple of buffer overruns have been fixed.
+** A couple of buffer overruns have been fixed.
-* Problems when closing files should now be reported.
+** Problems when closing files should now be reported.
-* Generated parsers should now work even on operating systems which do
+** Generated parsers should now work even on operating systems which do
-Changes in version 1.25, 1995-10-16:
+* Changes in version 1.25, 1995-10-16:
-* Errors in the input grammar are not fatal; Bison keeps reading
+** Errors in the input grammar are not fatal; Bison keeps reading
the grammar file, and reports all the errors found in it.
the grammar file, and reports all the errors found in it.
-* Tokens can now be specified as multiple-character strings: for
+** Tokens can now be specified as multiple-character strings: for
example, you could use "<=" for a token which looks like <=, instead
of chosing a name like LESSEQ.
example, you could use "<=" for a token which looks like <=, instead
of chosing a name like LESSEQ.
-* The %token_table declaration says to write a table of tokens (names
+** The %token_table declaration says to write a table of tokens (names
and numbers) into the parser file. The yylex function can use this
table to recognize multiple-character string tokens, or for other
purposes.
and numbers) into the parser file. The yylex function can use this
table to recognize multiple-character string tokens, or for other
purposes.
-* The %no_lines declaration says not to generate any #line preprocessor
+** The %no_lines declaration says not to generate any #line preprocessor
directives in the parser file.
directives in the parser file.
-* The %raw declaration says to use internal Bison token numbers, not
+** The %raw declaration says to use internal Bison token numbers, not
Yacc-compatible token numbers, when token names are defined as macros.
Yacc-compatible token numbers, when token names are defined as macros.
-* The --no-parser option produces the parser tables without including
+** The --no-parser option produces the parser tables without including
the parser engine; a project can now use its own parser engine.
The actions go into a separate file called NAME.act, in the form of
a switch statement body.
\f
the parser engine; a project can now use its own parser engine.
The actions go into a separate file called NAME.act, in the form of
a switch statement body.
\f
-Changes in version 1.23:
+* Changes in version 1.23:
The user can define YYPARSE_PARAM as the name of an argument to be
passed into yyparse. The argument should have type void *. It should
The user can define YYPARSE_PARAM as the name of an argument to be
passed into yyparse. The argument should have type void *. It should
Line numbers in output file corrected.
\f
Line numbers in output file corrected.
\f
-Changes in version 1.22:
+* Changes in version 1.22:
-Changes in version 1.20:
+* Changes in version 1.20:
Output file does not redefine const for C++.
Output file does not redefine const for C++.