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authorwiz <wiz@pkgsrc.org>2011-07-12 14:12:13 +0000
committerwiz <wiz@pkgsrc.org>2011-07-12 14:12:13 +0000
commit6249fce8dba78b4d1854344b9a43df4bdf37b10b (patch)
tree1e8feeca15c3f0a8dc02d4e5f27520d23f283180 /devel/bison/Makefile
parent4638f81f7fa3785eeeeb3b6d229ee0449a840665 (diff)
downloadpkgsrc-6249fce8dba78b4d1854344b9a43df4bdf37b10b.tar.gz
Update to 2.5:
* Changes in version 2.5 (2011-05-14): ** Grammar symbol names can now contain non-initial dashes: Consistently with directives (such as %error-verbose) and with %define variables (e.g. push-pull), grammar symbol names may contain dashes in any position except the beginning. This is a GNU extension over POSIX Yacc. Thus, use of this extension is reported by -Wyacc and rejected in Yacc mode (--yacc). ** Named references: Historically, Yacc and Bison have supported positional references ($n, $$) to allow access to symbol values from inside of semantic actions code. Starting from this version, Bison can also accept named references. When no ambiguity is possible, original symbol names may be used as named references: if_stmt : "if" cond_expr "then" then_stmt ';' { $if_stmt = mk_if_stmt($cond_expr, $then_stmt); } In the more common case, explicit names may be declared: stmt[res] : "if" expr[cond] "then" stmt[then] "else" stmt[else] ';' { $res = mk_if_stmt($cond, $then, $else); } Location information is also accessible using @name syntax. When accessing symbol names containing dots or dashes, explicit bracketing ($[sym.1]) must be used. These features are experimental in this version. More user feedback will help to stabilize them. ** IELR(1) and canonical LR(1): IELR(1) is a minimal LR(1) parser table generation algorithm. That is, given any context-free grammar, IELR(1) generates parser tables with the full language-recognition power of canonical LR(1) but with nearly the same number of parser states as LALR(1). This reduction in parser states is often an order of magnitude. More importantly, because canonical LR(1)'s extra parser states may contain duplicate conflicts in the case of non-LR(1) grammars, the number of conflicts for IELR(1) is often an order of magnitude less as well. This can significantly reduce the complexity of developing of a grammar. Bison can now generate IELR(1) and canonical LR(1) parser tables in place of its traditional LALR(1) parser tables, which remain the default. You can specify the type of parser tables in the grammar file with these directives: %define lr.type lalr %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'. 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. ** 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 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 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, IELR and LALR suffer the most. Canonical LR can suffer only if %nonassoc is used or if default reductions are enabled for inconsistent states. 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 power. Currently, LAC is only supported for deterministic parsers in C. You can enable LAC with the following directive: %define parse.lac full 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. ** %define improvements: *** Can now be invoked via the command line: Each of these command-line options -D NAME[=VALUE] --define=NAME[=VALUE] -F NAME[=VALUE] --force-define=NAME[=VALUE] is equivalent to this grammar file declaration %define NAME ["VALUE"] except that the manner in which Bison processes multiple definitions for the same NAME differs. Most importantly, -F and --force-define quietly override %define, but -D and --define do not. For further details, see the section `Bison Options' in the Bison manual. *** Variables renamed: The following %define variables api.push_pull lr.keep_unreachable_states have been renamed to api.push-pull lr.keep-unreachable-states The old names are now deprecated but will be maintained indefinitely for backward compatibility. *** Values no longer need to be quoted in the grammar file: If a %define value is an identifier, it no longer needs to be placed within quotations marks. For example, %define api.push-pull "push" can be rewritten as %define api.push-pull push *** Unrecognized variables are now errors not warnings. *** Multiple invocations for any variable is now an error not a warning. ** Unrecognized %code qualifiers are now errors not warnings. ** Character literals not of length one: Previously, Bison quietly converted all character literals to length one. For example, without warning, Bison interpreted the operators in the following grammar to be the same token: exp: exp '++' | exp '+' exp ; Bison now warns when a character literal is not of length one. In some future release, Bison will start reporting an error instead. ** 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. ** C++ parsers use YYRHSLOC: Similarly to the C parsers, the C++ parsers now define the YYRHSLOC macro and use it in the default YYLLOC_DEFAULT. You are encouraged to use it. If, for instance, your location structure has `first' and `last' members, instead of # define YYLLOC_DEFAULT(Current, Rhs, N) \ do \ if (N) \ { \ (Current).first = (Rhs)[1].location.first; \ (Current).last = (Rhs)[N].location.last; \ } \ else \ { \ (Current).first = (Current).last = (Rhs)[0].location.last; \ } \ while (false) use: # define YYLLOC_DEFAULT(Current, Rhs, N) \ do \ if (N) \ { \ (Current).first = YYRHSLOC (Rhs, 1).first; \ (Current).last = YYRHSLOC (Rhs, N).last; \ } \ else \ { \ (Current).first = (Current).last = YYRHSLOC (Rhs, 0).last; \ } \ while (false) ** YYLLOC_DEFAULT in C++: The default implementation of YYLLOC_DEFAULT used to be issued in the header file. It is now output in the implementation file, after the user %code sections so that its #ifndef guard does not try to override the user's YYLLOC_DEFAULT if provided. ** 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. ** Temporary hack for adding a semicolon to the user action: Previously, Bison appended a semicolon to every user action for reductions when the output language defaulted to C (specifically, when neither %yacc, %language, %skeleton, or equivalent command-line options were specified). This allowed actions such as exp: exp "+" exp { $$ = $1 + $3 }; instead of exp: exp "+" exp { $$ = $1 + $3; }; As a first step in removing this misfeature, Bison now issues a warning when it appends a semicolon. Moreover, in cases where Bison cannot easily determine whether a semicolon is needed (for example, an action ending with a cpp directive or a braced compound initializer), it no longer appends one. Thus, the C compiler might now complain about a missing semicolon where it did not before. Future releases of Bison will cease to append semicolons entirely. ** Verbose syntax error message fixes: 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 in order to detect a syntax error. Because no unexpected token or expected tokens can then be reported, the verbose syntax error message described above is suppressed, and the parser instead reports the simpler message, `syntax error'. Previously, this suppression was sometimes erroneously triggered by %nonassoc when a lookahead was actually required. Now verbose messages are suppressed only when all previous lookaheads have already been shifted or discarded. *** Previously, the list of expected tokens erroneously included tokens that would actually induce a syntax error because conflicts for them were resolved with %nonassoc in the current parser state. Such tokens are now properly omitted from the list. *** Expected token lists are still often wrong due to state merging (from LALR or IELR) and default reductions, which can both add invalid tokens and subtract valid tokens. Canonical LR almost completely fixes this problem by eliminating state merging and default reductions. However, there is one minor problem left even when using canonical LR and even after the fixes above. That is, if the resolution of a conflict with %nonassoc appears in a later parser state than the one at which some syntax error is discovered, the conflicted token is still erroneously included in the expected token list. Bison's new LAC implementation, described above, eliminates this problem and the need for 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. *** Parser traces now print the top element of the stack. ** -W/--warnings fixes: *** Bison now properly recognizes the `no-' versions of categories: For example, given the following command line, Bison now enables all warnings except warnings for incompatibilities with POSIX Yacc: bison -Wall,no-yacc gram.y *** Bison now treats S/R and R/R conflicts like other warnings: Previously, conflict reports were independent of Bison's normal warning system. Now, Bison recognizes the warning categories `conflicts-sr' and `conflicts-rr'. This change has important consequences for the -W and --warnings command-line options. For example: bison -Wno-conflicts-sr gram.y # S/R conflicts not reported bison -Wno-conflicts-rr gram.y # R/R conflicts not reported bison -Wnone gram.y # no conflicts are reported bison -Werror gram.y # any conflict is an error However, as before, if the %expect or %expect-rr directive is specified, an unexpected number of conflicts is an error, and an expected number of conflicts is not reported, so -W and --warning then have no effect on the conflict report. *** The `none' category no longer disables a preceding `error': For example, for the following command line, Bison now reports errors instead of warnings for incompatibilities with POSIX Yacc: bison -Werror,none,yacc gram.y *** The `none' category now disables all Bison warnings: Previously, the `none' category disabled only Bison warnings for which there existed a specific -W/--warning category. However, given the following command line, Bison is now guaranteed to suppress all warnings: bison -Wnone gram.y ** Precedence directives can now assign token number 0: Since Bison 2.3b, which restored the ability of precedence directives to assign token numbers, doing so for token number 0 has produced an assertion failure. For example: %left END 0 This bug has been fixed.
Diffstat (limited to 'devel/bison/Makefile')
-rw-r--r--devel/bison/Makefile12
1 files changed, 6 insertions, 6 deletions
diff --git a/devel/bison/Makefile b/devel/bison/Makefile
index 557d6393cde..d6a28a9107f 100644
--- a/devel/bison/Makefile
+++ b/devel/bison/Makefile
@@ -1,7 +1,6 @@
-# $NetBSD: Makefile,v 1.76 2011/04/22 13:43:15 obache Exp $
+# $NetBSD: Makefile,v 1.77 2011/07/12 14:12:13 wiz Exp $
-DISTNAME= bison-2.4.3
-PKGREVISION= 1
+DISTNAME= bison-2.5
CATEGORIES= devel
MASTER_SITES= ${MASTER_SITE_GNU:=bison/}
EXTRACT_SUFX= .tar.bz2
@@ -18,7 +17,7 @@ GNU_CONFIGURE= YES
USE_LANGUAGES= c c++
USE_PKGLOCALEDIR= yes
USE_TOOLS+= grep gm4:run msgfmt
-INFO_FILES= # PLIST
+INFO_FILES= yes
CONFIGURE_ENV+= gt_cv_func_gnugettext1_libintl=yes \
ac_cv_prog_M4=${TOOLS_PATH.gm4}
@@ -29,8 +28,9 @@ TEST_TARGET= check
pre-build:
${TOUCH} ${WRKSRC}/doc/bison.1
-# "bison" wants a recent version of "gettext" which at least NetBSD doesn't
-# provide. Figure out whether it will install the locale files or not.
+# "bison" wants a recent version of "gettext" which at least some
+# NetBSD versions don't provide. Figure out whether it will install
+# the locale files or not.
PLIST_SRC= ${WRKDIR}/PLIST
post-configure: