* Noteworthy changes in release ?.? (????-??-??) [?]
- ** New format for error reports: carets
+** Incompatible changes
+
+*** Obsolete features
+
+ Support for YYFAIL is removed (deprecated in Bison 2.4.2).
+ Support for yystype and yyltype (instead of YYSTYPE and YYLTYPE)
+ is removed (deprecated in Bison 1.875).
+ Support for YYPARSE_PARAM is removed (deprecated in Bison 1.875).
+
+** Warnings
+
+*** Enhancements of the -Werror option
+
+ The -Werror=CATEGORY option is now recognized, and will treat specified
+ warnings as errors. The warnings need not have been explicitly activated
+ using the -W option, this is similar to what GCC 4.7 does.
+
+ For example, given the following command line, Bison will treat both
+ warnings related to POSIX Yacc incompatibilities and S/R conflicts as
+ errors (and only those):
+
+ $ bison -Werror=yacc,error=conflicts-sr input.y
+
+ If no categories are specified, -Werror will make all active warnings into
+ errors. For example, the following line does the same the previous example:
+
+ $ bison -Werror -Wnone -Wyacc -Wconflicts-sr input.y
+
+ (By default -Wconflicts-sr,conflicts-rr,deprecated,other is enabled.)
+
+ Note that the categories in this -Werror option may not be prefixed with
+ "no-". However, -Wno-error[=CATEGORY] is valid.
+
+ Note that -y enables -Werror=yacc. Therefore it is now possible to require
+ Yacc-like behavior (e.g., always generate y.tab.c), but to report
+ incompatibilities as warnings: "-y -Wno-error=yacc".
+
+*** The display of warnings is now richer
+
+ The option that controls a given warning is now displayed:
+
+ foo.y:4.6: warning: type clash on default action: <foo> != <bar> [-Wother]
+
+ In the case of warnings treated as errors, the prefix is changed from
+ "warning: " to "error: ", and the suffix is displayed, in a manner similar
+ to GCC, as [-Werror=CATEGORY].
+
+ For instance, where the previous version of Bison would report (and exit
+ with failure):
+
+ bison: warnings being treated as errors
+ input.y:1.1: warning: stray ',' treated as white space
+
+ it now reports:
+
+ input.y:1.1: error: stray ',' treated as white space [-Werror=other]
+
+*** Deprecated constructs
+
+ The new 'deprecated' warning category flags obsolete constructs whose
+ support will be discontinued. It is enabled by default. These warnings
+ used to be reported as 'other' warnings.
+
+*** Useless semantic types
+
+ Bison now warns about useless (uninhabited) semantic types. Since
+ semantic types are not declared to Bison (they are defined in the opaque
+ %union structure), it is %printer/%destructor directives about useless
+ types that trigger the warning:
+
+ %token <type1> term
+ %type <type2> nterm
+ %printer {} <type1> <type3>
+ %destructor {} <type2> <type4>
+ %%
+ nterm: term { $$ = $1; };
+
+ 3.28-34: warning: type <type3> is used, but is not associated to any symbol
+ 4.28-34: warning: type <type4> is used, but is not associated to any symbol
+
+*** Undefined but unused symbols
+
+ Bison used to raise an error for undefined symbols that are not used in
+ the grammar. This is now only a warning.
+
+ %printer {} symbol1
+ %destructor {} symbol2
+ %type <type> symbol3
+ %%
+ exp: "a";
+
+*** Useless destructors or printers
+
+ Bison now warns about useless destructors or printers. In the following
+ example, the printer for <type1>, and the destructor for <type2> are
+ useless: all symbols of <type1> (token1) already have a printer, and all
+ symbols of type <type2> (token2) already have a destructor.
+
+ %token <type1> token1
+ <type2> token2
+ <type3> token3
+ <type4> token4
+ %printer {} token1 <type1> <type3>
+ %destructor {} token2 <type2> <type4>
+
+*** Conflicts
+
+ The warnings and error messages about shift/reduce and reduce/reduce
+ conflicts have been normalized. For instance on the following foo.y file:
+
+ %glr-parser
+ %%
+ exp: exp '+' exp | '0' | '0';
+
+ compare the previous version of bison:
+
+ $ bison foo.y
+ foo.y: conflicts: 1 shift/reduce, 2 reduce/reduce
+ $ bison -Werror foo.y
+ bison: warnings being treated as errors
+ foo.y: conflicts: 1 shift/reduce, 2 reduce/reduce
+
+ with the new behavior:
+
+ $ bison foo.y
+ foo.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
+ foo.y: warning: 2 reduce/reduce conflicts [-Wconflicts-rr]
+ $ bison -Werror foo.y
+ foo.y: error: 1 shift/reduce conflict [-Werror=conflicts-sr]
+ foo.y: error: 2 reduce/reduce conflicts [-Werror=conflicts-rr]
+
+ When %expect or %expect-rr is used, such as with bar.y:
+
+ %expect 0
+ %glr-parser
+ %%
+ exp: exp '+' exp | '0' | '0';
+
+ Former behavior:
+
+ $ bison bar.y
+ bar.y: conflicts: 1 shift/reduce, 2 reduce/reduce
+ bar.y: expected 0 shift/reduce conflicts
+ bar.y: expected 0 reduce/reduce conflicts
+
+ New one:
+
+ $ bison bar.y
+ bar.y: error: shift/reduce conflicts: 1 found, 0 expected
+ bar.y: error: reduce/reduce conflicts: 2 found, 0 expected
+
+** Additional yylex/yyparse arguments
+
+ The new directive %param declares additional arguments to both yylex and
+ yyparse. The %lex-param, %parse-param, and %param directives support one
+ or more arguments. Instead of
+
+ %lex-param {arg1_type *arg1}
+ %lex-param {arg2_type *arg2}
+ %parse-param {arg1_type *arg1}
+ %parse-param {arg2_type *arg2}
+
+ one may now declare
+
+ %param {arg1_type *arg1} {arg2_type *arg2}
+
+** Java skeleton improvements
+
+ The constants for token names were moved to the Lexer interface. Also, it
+ is possible to add code to the parser's constructors using "%code init"
+ and "%define init_throws".
+
+** C++ skeletons improvements
+
+*** The parser header is no longer mandatory (lalr1.cc, glr.cc)
+
+ Using %defines is now optional. Without it, the needed support classes
+ are defined in the generated parser, instead of additional files (such as
+ location.hh, position.hh and stack.hh).
+
+*** Locations are no longer mandatory (lalr1.cc, glr.cc)
+
+ Both lalr1.cc and glr.cc no longer require %location.
+
+*** syntax_error exception (lalr1.cc)
+
+ The C++ parser features a syntax_error exception, which can be
+ thrown from the scanner or from user rules to raise syntax errors.
+ This facilitates reporting errors caught in sub-functions (e.g.,
+ rejecting too large integral literals from a conversion function
+ used by the scanner, or rejecting invalid combinations from a
+ factory invoked by the user actions).
+
+** Variable api.token.prefix
+
+ The variable api.token.prefix changes the way tokens are identified in
+ the generated files. This is especially useful to avoid collisions
+ with identifiers in the target language. For instance
+
+ %token FILE for ERROR
+ %define api.token.prefix "TOK_"
+ %%
+ start: FILE for ERROR;
+
+ will generate the definition of the symbols TOK_FILE, TOK_for, and
+ TOK_ERROR in the generated sources. In particular, the scanner must
+ use these prefixed token names, although the grammar itself still
+ uses the short names (as in the sample rule given above).
+
+** Renamed %define variables
+
+ The following variables have been renamed for consistency. Backward
+ compatibility is ensured, but upgrading is recommended.
+
+ lr.default-reductions -> lr.default-reduction
+ lr.keep-unreachable-states -> lr.keep-unreachable-state
+ namespace -> api.namespace
+
+** Variable parse.error
+
+ This variable controls the verbosity of error messages. The use of the
+ %error-verbose directive is deprecated in favor of "%define parse.error
+ verbose".
+
+** Semantic predicates
+
+ The new, experimental, semantic-predicate feature allows actions of the
+ form "%?{ BOOLEAN-EXPRESSION }", which cause syntax errors (as for
+ YYERROR) if the expression evaluates to 0, and are evaluated immediately
+ in GLR parsers, rather than being deferred. The result is that they allow
+ the programmer to prune possible parses based on the values of run-time
+ expressions.
+
+** The directive %expect-rr is now an error in non GLR mode
+
+ It used to be an error only if used in non GLR mode, _and_ if there are
+ reduce/reduce conflicts.
+
+* Noteworthy changes in release ?.? (????-??-??) [?]
+
+** %language is no longer an experimental feature.
+
+ The introduction of this feature, in 2.4, was four years ago. The --language
+ option and the %language directive are no longer experimental.
+
+ ** Bug fixes
- Caret errors have been added to Bison, for example (taken from the
- documentation):
+ Warnings about uninitialized yylloc in yyparse have been fixed.
- input.y:3.20-23: error: ambiguous reference: '$exp'
- exp: exp '+' exp { $exp = $1 + $2; };
- ^^^^
+ ** Diagnostics are improved
- The default behaviour for now is still not to display these unless explictly
- asked with -fall of -fcaret. However, in a later release, it will be made the
- default behavior (but may still be deactivated with -fno-caret).
+ *** Changes in the format of error messages
- ** New value for %define variable: api.pure full
+ This used to be the format of many error reports:
- The %define variable api.pure requests a pure (reentrant) parser. However,
- for historical reasons, using it in a location-tracking Yacc parser resulted
- in an yyerror function that did not take a location as a parameter. With this
- new value, the user may request a better pure parser, where yyerror does take
- a location as a parameter (in location-tracking parsers).
+ input.y:2.7-12: %type redeclaration for exp
+ input.y:1.7-12: previous declaration
- The use of "%define api.pure true" is deprecated in favor of this new
- "%define api.pure full".
+ It is now:
- ** Changes in the format of error messages
+ input.y:2.7-12: error: %type redeclaration for exp
+ input.y:1.7-12: previous declaration
- This used to be the format of many error reports:
+ *** New format for error reports: carets
- foo.y:5.10-24: result type clash on merge function 'merge': <t3> != <t2>
- foo.y:4.13-27: previous declaration
+ Caret errors have been added to Bison:
- It is now:
+ input.y:2.7-12: error: %type redeclaration for exp
+ %type <sval> exp
+ ^^^^^^
+ input.y:1.7-12: previous declaration
+ %type <ival> exp
+ ^^^^^^
- foo.y:5.10-25: result type clash on merge function 'merge': <t3> != <t2>
- foo.y:4.13-27: previous declaration
+ or
- ** Exception safety (lalr1.cc)
+ input.y:3.20-23: error: ambiguous reference: '$exp'
+ exp: exp '+' exp { $exp = $1 + $3; };
+ ^^^^
+ input.y:3.1-3: refers to: $exp at $$
+ exp: exp '+' exp { $exp = $1 + $3; };
+ ^^^
+ input.y:3.6-8: refers to: $exp at $1
+ exp: exp '+' exp { $exp = $1 + $3; };
+ ^^^
+ input.y:3.14-16: refers to: $exp at $3
+ exp: exp '+' exp { $exp = $1 + $3; };
+ ^^^
+
+ The default behaviour for now is still not to display these unless
+ explictly asked with -fcaret (or -fall). However, in a later release, it
+ will be made the default behavior (but may still be deactivated with
+ -fno-caret).
- The parse function now catches exceptions, uses the %destructors to
- release memory (the lookahead symbol and the symbols pushed on the stack)
- before re-throwing the exception.
+ ** New value for %define variable: api.pure full
- This feature is somewhat experimental. User feedback would be
- appreciated.
+ The %define variable api.pure requests a pure (reentrant) parser. However,
+ for historical reasons, using it in a location-tracking Yacc parser
+ resulted in a yyerror function that did not take a location as a
+ parameter. With this new value, the user may request a better pure parser,
+ where yyerror does take a location as a parameter (in location-tracking
+ parsers).
+
+ The use of "%define api.pure true" is deprecated in favor of this new
+ "%define api.pure full".
** New %define variable: api.location.type (glr.cc, lalr1.cc, lalr1.java)
position_type are deprecated in favor of api.location.type and
api.position.type.
+ ** Exception safety (lalr1.cc)
+
+ The parse function now catches exceptions, uses the %destructors to
+ release memory (the lookahead symbol and the symbols pushed on the stack)
+ before re-throwing the exception.
+
+ This feature is somewhat experimental. User feedback would be
+ appreciated.
+
** Graph improvements in DOT and XSLT
The graphical presentation of the states is more readable: their shape is
These changes are present in both --graph output and xml2dot.xsl XSLT
processing, with minor (documented) differences.
- Two nodes were added to the documentation: Xml and Graphviz.
-
- * Noteworthy changes in release ?.? (????-??-??) [?]
-
- ** Bug fixes
+ ** %language is no longer an experimental feature.
- Warnings about uninitialized yylloc in yyparse have been fixed.
+ The introduction of this feature, in 2.4, was four years ago. The
+ --language option and the %language directive are no longer experimental.
** Documentation
The sections about shift/reduce and reduce/reduce conflicts resolution
have been fixed and extended.
+ Although introduced more than four years ago, XML and Graphviz reports
+ were not properly documented.
+
+ The translation of mid-rule actions is now described.
+
* Noteworthy changes in release 2.6.5 (2012-11-07) [stable]
We consider compiler warnings about Bison generated parsers to be bugs.
* Noteworthy changes in release 2.6.1 (2012-07-30) [stable]
- Bison no longer executes user-specified M4 code when processing a grammar.
+ Bison no longer executes user-specified M4 code when processing a grammar.
** Future Changes
* Noteworthy changes in release 2.6 (2012-07-19) [stable]
-** Future Changes
+** Future changes
The next major release of Bison will drop support for the following
deprecated features. Please report disagreements to bug-bison@gnu.org.
LocalWords: namespaces strerror const autoconfiguration Dconst Autoconf's FDL
LocalWords: Automake TMPDIR LESSEQ ylwrap endif yydebug YYTOKEN YYLSP ival hh
LocalWords: extern YYTOKENTYPE TOKENTYPE yytokentype tokentype STYPE lval pdf
- LocalWords: lang yyoutput dvi html ps POSIX lvalp llocp calc yyo fval Wmaybe
- LocalWords: yyvsp pragmas noreturn java's
+ LocalWords: lang yyoutput dvi html ps POSIX lvalp llocp Wother nterm arg init
+ LocalWords: TOK calc yyo fval Wconflicts
Local Variables:
mode: outline
ftp://$(gnu_rel_host)/gnu/bison
# Tests not to run as part of "make distcheck".
-# Exclude changelog-check here so that there's less churn in ChangeLog
-# files -- otherwise, you'd need to have the upcoming version number
-# at the top of the file for each `make distcheck' run.
-local-checks-to-skip = \
- changelog-check \
+local-checks-to-skip = \
sc_immutable_NEWS \
- sc_prohibit_always_true_header_tests \
- sc_prohibit_atoi_atof \
- sc_prohibit_strcmp
+ sc_prohibit_atoi_atof
# The local directory containing the checked-out copy of gnulib used in
# this release. Used solely to get a date for the "announcement" target.
prohibit_always-defined_macros+=?|^src/(parse-gram.c|system.h)$$ \
prohibit_always-defined_macros+=?|^tests/regression.at$$ \
prohibit_defined_have_decl_tests=?|^lib/timevar.c$$ \
+ prohibit_doubled_word=^tests/named-refs.at$$ \
prohibit_magic_number_exit=^doc/bison.texi$$ \
prohibit_magic_number_exit+=?|^tests/(conflicts|regression).at$$ \
+ prohibit_strcmp=^doc/bison\.texi$$ \
require_config_h_first=^(lib/yyerror|data/(glr|yacc))\.c$$ \
space_tab=^tests/(input|c\+\+)\.at$$ \
- trailing_blank=^src/parse-gram.[ch]$$ \
unmarked_diagnostics=^(djgpp/|doc/bison.texi$$|tests/c\+\+\.at$$) \
)
# releases, we want to be able run make dist without being required to
# add a bogus NEWS entry. In that case, the version string
# automatically contains a dash, which we also let disable gnits.
-AM_INIT_AUTOMAKE([1.11.1 dist-xz silent-rules]
+AM_INIT_AUTOMAKE([1.11.1 dist-xz nostdinc
+ color-tests parallel-tests
+ silent-rules]
m4_bmatch(m4_defn([AC_PACKAGE_VERSION]), [[-_]],
[gnu], [gnits]))
AM_SILENT_RULES([yes])
# Gnulib (early checks).
gl_EARLY
+ # Gnulib uses '#pragma GCC diagnostic push' to silence some
+ # warnings, but older gcc doesn't support this.
+ AC_CACHE_CHECK([whether pragma GCC diagnostic push works],
+ [lv_cv_gcc_pragma_push_works], [
+ save_CFLAGS=$CFLAGS
+ CFLAGS='-Wunknown-pragmas -Werror'
+ AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
+ #pragma GCC diagnostic push
+ #pragma GCC diagnostic pop
+ ]])],
+ [lv_cv_gcc_pragma_push_works=yes],
+ [lv_cv_gcc_pragma_push_works=no])
+ CFLAGS=$save_CFLAGS])
+
AC_ARG_ENABLE([gcc-warnings],
[ --enable-gcc-warnings turn on lots of GCC warnings (not recommended)],
[case $enable_gcc_warnings in
[enable_gcc_warnings=no])
if test "$enable_gcc_warnings" = yes; then
warn_common='-Wall -Wextra -Wno-sign-compare -Wcast-align
- -Wcast-qual -Wformat -Wpointer-arith -Wwrite-strings'
- warn_c='-Wbad-function-cast -Wmissing-declarations -Wmissing-prototypes
- -Wshadow -Wstrict-prototypes'
+ -Wformat -Wpointer-arith -Wwrite-strings'
+ warn_c='-Wbad-function-cast -Wshadow -Wstrict-prototypes'
warn_cxx='-Wnoexcept'
+
AC_LANG_PUSH([C])
# Clang supports many of GCC's -W options, but only issues warnings
# on the ones it does not recognize. In that case, gl_WARN_ADD
gl_WARN_ADD([$i], [WARN_CFLAGS])
done
gl_WARN_ADD([-Werror], [WERROR_CFLAGS])
+
+ # Warnings for the test suite, and maybe for bison if GCC is modern
+ # enough.
+ gl_WARN_ADD([-Wmissing-declarations], [WARN_CFLAGS_TEST])
+ gl_WARN_ADD([-Wmissing-prototypes], [WARN_CFLAGS_TEST])
+ test $lv_cv_gcc_pragma_push_works = yes &&
+ AS_VAR_APPEND([WARN_CFLAGS], [" $WARN_CFLAGS_TEST"])
+
# Warnings for the test suite only.
gl_WARN_ADD([-Wundef], [WARN_CFLAGS_TEST])
gl_WARN_ADD([-pedantic], [WARN_CFLAGS_TEST])
CFLAGS=$save_CFLAGS
AC_LANG_POP([C])
+
AC_LANG_PUSH([C++])
save_CXXFLAGS=$CXXFLAGS
gl_WARN_ADD([-Werror=unknown-warning-option], [CXXFLAGS])
# Warnings for the test suite only.
gl_WARN_ADD([-Wundef], [WARN_CXXFLAGS_TEST])
gl_WARN_ADD([-pedantic], [WARN_CXXFLAGS_TEST])
+ # Variants break strict aliasing analysis.
+ gl_WARN_ADD([-fno-strict-aliasing], [NO_STRICT_ALIAS_CXXFLAGS])
CXXFLAGS=$save_CXXFLAGS
AC_LANG_POP([C++])
fi
BISON_TEST_FOR_WORKING_C_COMPILER
- BISON_TEST_FOR_WORKING_CXX_COMPILER
BISON_C_COMPILER_POSIXLY_CORRECT
+ BISON_TEST_FOR_WORKING_CXX_COMPILER
+ BISON_CXX_COMPILER_POSIXLY_CORRECT
AC_ARG_ENABLE([yacc],
[AC_HELP_STRING([--disable-yacc],
, [enable_yacc=yes])
case $enable_yacc in
yes)
- YACC_SCRIPT=yacc
- YACC_LIBRARY=liby.a;;
+ YACC_SCRIPT=src/yacc
+ YACC_LIBRARY=lib/liby.a;;
*)
YACC_SCRIPT=
YACC_LIBRARY=;;
# Initialize the test suite.
AC_CONFIG_TESTDIR(tests)
-AC_CONFIG_FILES([tests/Makefile tests/atlocal])
+AC_CONFIG_FILES([tests/atlocal])
AC_CONFIG_FILES([tests/bison], [chmod +x tests/bison])
AC_CHECK_PROGS([VALGRIND], [valgrind])
case $VALGRIND:$host_os in
# Needed by tests/atlocal.in.
AC_SUBST([GCC])
-gt_JAVACOMP([1.3])
+gt_JAVACOMP([1.3], [1.4])
gt_JAVAEXEC
AC_CONFIG_FILES([Makefile
- build-aux/Makefile
- po/Makefile.in
- data/Makefile
- etc/Makefile
- examples/Makefile
- examples/calc++/Makefile
- lib/Makefile src/Makefile
- doc/Makefile
- doc/yacc.1])
+ po/Makefile.in
+ doc/yacc.1])
AC_OUTPUT
* Simple GLR Parsers:: Using GLR parsers on unambiguous grammars.
* Merging GLR Parses:: Using GLR parsers to resolve ambiguities.
-* GLR Semantic Actions:: Deferred semantic actions have special concerns.
+* GLR Semantic Actions:: Considerations for semantic values and deferred actions.
+* Semantic Predicates:: Controlling a parse with arbitrary computations.
* Compiler Requirements:: GLR parsers require a modern C compiler.
Examples
Grammar Rules for @code{rpcalc}
-* Rpcalc Input::
-* Rpcalc Line::
-* Rpcalc Expr::
+* Rpcalc Input:: Explanation of the @code{input} nonterminal
+* Rpcalc Line:: Explanation of the @code{line} nonterminal
+* Rpcalc Expr:: Explanation of the @code{expr} nonterminal
Location Tracking Calculator: @code{ltcalc}
* Mfcalc Declarations:: Bison declarations for multi-function calculator.
* Mfcalc Rules:: Grammar rules for the calculator.
* Mfcalc Symbol Table:: Symbol table management subroutines.
+* Mfcalc Lexer:: The lexical analyzer.
+* Mfcalc Main:: The controlling function.
Bison Grammar Files
This says when, why and how to use the exceptional
action in the middle of a rule.
+ Actions in Mid-Rule
+
+ * Using Mid-Rule Actions:: Putting an action in the middle of a rule.
+ * Mid-Rule Action Translation:: How mid-rule actions are actually processed.
+ * Mid-Rule Conflicts:: Mid-rule actions can cause conflicts.
+
Tracking Locations
* Location Type:: Specifying a data type for locations.
Operator Precedence
* Why Precedence:: An example showing why precedence is needed.
-* Using Precedence:: How to specify precedence in Bison grammars.
+* Using Precedence:: How to specify precedence and associativity.
+* Precedence Only:: How to specify precedence only.
* Precedence Examples:: How these features are used in the previous example.
* How Precedence:: How they work.
* Non Operators:: Using precedence for general conflicts.
@menu
* Simple GLR Parsers:: Using GLR parsers on unambiguous grammars.
* Merging GLR Parses:: Using GLR parsers to resolve ambiguities.
-* GLR Semantic Actions:: Deferred semantic actions have special concerns.
+* GLR Semantic Actions:: Considerations for semantic values and deferred actions.
+* Semantic Predicates:: Controlling a parse with arbitrary computations.
* Compiler Requirements:: GLR parsers require a modern C compiler.
@end menu
@end group
%%
-
-@group
type_decl: TYPE ID '=' type ';' ;
-@end group
@group
type:
@node GLR Semantic Actions
@subsection GLR Semantic Actions
+The nature of GLR parsing and the structure of the generated
+parsers give rise to certain restrictions on semantic values and actions.
+
+@subsubsection Deferred semantic actions
@cindex deferred semantic actions
By definition, a deferred semantic action is not performed at the same time as
the associated reduction.
to invoke @code{yyclearin} (@pxref{Action Features}) or to attempt to free
memory referenced by @code{yylval}.
+@subsubsection YYERROR
@findex YYERROR
@cindex GLR parsers and @code{YYERROR}
Another Bison feature requiring special consideration is @code{YYERROR}
initiate error recovery.
During deterministic GLR operation, the effect of @code{YYERROR} is
the same as its effect in a deterministic parser.
-In a deferred semantic action, its effect is undefined.
-@c The effect is probably a syntax error at the split point.
+The effect in a deferred action is similar, but the precise point of the
+error is undefined; instead, the parser reverts to deterministic operation,
+selecting an unspecified stack on which to continue with a syntax error.
+In a semantic predicate (see @ref{Semantic Predicates}) during nondeterministic
+parsing, @code{YYERROR} silently prunes
+the parse that invoked the test.
+
+@subsubsection Restrictions on semantic values and locations
+GLR parsers require that you use POD (Plain Old Data) types for
+semantic values and location types when using the generated parsers as
+C++ code.
+
+@node Semantic Predicates
+@subsection Controlling a Parse with Arbitrary Predicates
+@findex %?
+@cindex Semantic predicates in GLR parsers
+
+In addition to the @code{%dprec} and @code{%merge} directives,
+GLR parsers
+allow you to reject parses on the basis of arbitrary computations executed
+in user code, without having Bison treat this rejection as an error
+if there are alternative parses. (This feature is experimental and may
+evolve. We welcome user feedback.) For example,
+
+@example
+widget:
+ %?@{ new_syntax @} "widget" id new_args @{ $$ = f($3, $4); @}
+| %?@{ !new_syntax @} "widget" id old_args @{ $$ = f($3, $4); @}
+;
+@end example
+
+@noindent
+is one way to allow the same parser to handle two different syntaxes for
+widgets. The clause preceded by @code{%?} is treated like an ordinary
+action, except that its text is treated as an expression and is always
+evaluated immediately (even when in nondeterministic mode). If the
+expression yields 0 (false), the clause is treated as a syntax error,
+which, in a nondeterministic parser, causes the stack in which it is reduced
+to die. In a deterministic parser, it acts like YYERROR.
+
+As the example shows, predicates otherwise look like semantic actions, and
+therefore you must be take them into account when determining the numbers
+to use for denoting the semantic values of right-hand side symbols.
+Predicate actions, however, have no defined value, and may not be given
+labels.
+
+There is a subtle difference between semantic predicates and ordinary
+actions in nondeterministic mode, since the latter are deferred.
+For example, we could try to rewrite the previous example as
+
+@example
+widget:
+ @{ if (!new_syntax) YYERROR; @}
+ "widget" id new_args @{ $$ = f($3, $4); @}
+| @{ if (new_syntax) YYERROR; @}
+ "widget" id old_args @{ $$ = f($3, $4); @}
+;
+@end example
+
+@noindent
+(reversing the sense of the predicate tests to cause an error when they are
+false). However, this
+does @emph{not} have the same effect if @code{new_args} and @code{old_args}
+have overlapping syntax.
+Since the mid-rule actions testing @code{new_syntax} are deferred,
+a GLR parser first encounters the unresolved ambiguous reduction
+for cases where @code{new_args} and @code{old_args} recognize the same string
+@emph{before} performing the tests of @code{new_syntax}. It therefore
+reports an error.
-Also, see @ref{Location Default Action, ,Default Action for Locations}, which
-describes a special usage of @code{YYLLOC_DEFAULT} in GLR parsers.
+Finally, be careful in writing predicates: deferred actions have not been
+evaluated, so that using them in a predicate will have undefined effects.
@node Compiler Requirements
@subsection Considerations when Compiling GLR Parsers
Here are the C and Bison declarations for the reverse polish notation
calculator. As in C, comments are placed between @samp{/*@dots{}*/}.
+@comment file: rpcalc.y
@example
/* Reverse polish notation calculator. */
%@{
#define YYSTYPE double
+ #include <stdio.h>
#include <math.h>
int yylex (void);
void yyerror (char const *);
Here are the grammar rules for the reverse polish notation calculator.
+@comment file: rpcalc.y
@example
@group
input:
rule are referred to as @code{$1}, @code{$2}, and so on.
@menu
-* Rpcalc Input::
-* Rpcalc Line::
-* Rpcalc Expr::
+* Rpcalc Input:: Explanation of the @code{input} nonterminal
+* Rpcalc Line:: Explanation of the @code{line} nonterminal
+* Rpcalc Expr:: Explanation of the @code{expr} nonterminal
@end menu
@node Rpcalc Input
Here is the code for the lexical analyzer:
+@comment file: rpcalc.y
@example
@group
/* The lexical analyzer returns a double floating point
kept to the bare minimum. The only requirement is that it call
@code{yyparse} to start the process of parsing.
+@comment file: rpcalc.y
@example
@group
int
@code{yyerror} (@pxref{Interface, ,Parser C-Language Interface}), so
here is the definition we will use:
+@comment file: rpcalc.y
@example
-@group
#include <stdio.h>
-@end group
@group
/* Called by yyparse on error. */
@example
$ @kbd{rpcalc}
@kbd{4 9 +}
-13
+@result{} 13
@kbd{3 7 + 3 4 5 *+-}
--13
+@result{} -13
@kbd{3 7 + 3 4 5 * + - n} @r{Note the unary minus, @samp{n}}
-13
+@result{} 13
@kbd{5 6 / 4 n +}
--3.166666667
+@result{} -3.166666667
@kbd{3 4 ^} @r{Exponentiation}
-81
+@result{} 81
@kbd{^D} @r{End-of-file indicator}
$
@end example
%token NUM
%left '-' '+'
%left '*' '/'
-%left NEG /* negation--unary minus */
-%right '^' /* exponentiation */
+%precedence NEG /* negation--unary minus */
+%right '^' /* exponentiation */
@end group
%% /* The grammar follows. */
types and says they are left-associative operators. The declarations
@code{%left} and @code{%right} (right associativity) take the place of
@code{%token} which is used to declare a token type name without
-associativity. (These tokens are single-character literals, which
+associativity/precedence. (These tokens are single-character literals, which
ordinarily don't need to be declared. We declare them here to specify
-the associativity.)
+the associativity/precedence.)
Operator precedence is determined by the line ordering of the
declarations; the higher the line number of the declaration (lower on
the page or screen), the higher the precedence. Hence, exponentiation
has the highest precedence, unary minus (@code{NEG}) is next, followed
-by @samp{*} and @samp{/}, and so on. @xref{Precedence, ,Operator
+by @samp{*} and @samp{/}, and so on. Unary minus is not associative,
+only precedence matters (@code{%precedence}. @xref{Precedence, ,Operator
Precedence}.
The other important new feature is the @code{%prec} in the grammar
%left '-' '+'
%left '*' '/'
-%left NEG
+%precedence NEG
%right '^'
%% /* The grammar follows. */
Here is a sample session with the multi-function calculator:
@example
+@group
$ @kbd{mfcalc}
@kbd{pi = 3.141592653589}
-3.1415926536
+@result{} 3.1415926536
+@end group
+@group
@kbd{sin(pi)}
-0.0000000000
+@result{} 0.0000000000
+@end group
@kbd{alpha = beta1 = 2.3}
-2.3000000000
+@result{} 2.3000000000
@kbd{alpha}
-2.3000000000
+@result{} 2.3000000000
@kbd{ln(alpha)}
-0.8329091229
+@result{} 0.8329091229
@kbd{exp(ln(beta1))}
-2.3000000000
+@result{} 2.3000000000
$
@end example
* Mfcalc Declarations:: Bison declarations for multi-function calculator.
* Mfcalc Rules:: Grammar rules for the calculator.
* Mfcalc Symbol Table:: Symbol table management subroutines.
+* Mfcalc Lexer:: The lexical analyzer.
+* Mfcalc Main:: The controlling function.
@end menu
@node Mfcalc Declarations
@example
@group
%@{
- #include <math.h> /* For math functions, cos(), sin(), etc. */
- #include "calc.h" /* Contains definition of `symrec'. */
+ #include <stdio.h> /* For printf, etc. */
+ #include <math.h> /* For pow, used in the grammar. */
+ #include "calc.h" /* Contains definition of `symrec'. */
int yylex (void);
void yyerror (char const *);
%@}
%right '='
%left '-' '+'
%left '*' '/'
-%left NEG /* negation--unary minus */
-%right '^' /* exponentiation */
+%precedence NEG /* negation--unary minus */
+%right '^' /* exponentiation */
@end group
@end example
@end group
@end example
-The new version of @code{main} includes a call to @code{init_table}, a
-function that initializes the symbol table. Here it is, and
-@code{init_table} as well:
+The new version of @code{main} will call @code{init_table} to initialize
+the symbol table:
@comment file: mfcalc.y: 3
@example
-#include <stdio.h>
-
-@group
-/* Called by yyparse on error. */
-void
-yyerror (char const *s)
-@{
- fprintf (stderr, "%s\n", s);
-@}
-@end group
-
@group
struct init
@{
@group
struct init const arith_fncts[] =
@{
- "sin", sin,
- "cos", cos,
- "atan", atan,
- "ln", log,
- "exp", exp,
- "sqrt", sqrt,
- 0, 0
+ @{ "atan", atan @},
+ @{ "cos", cos @},
+ @{ "exp", exp @},
+ @{ "ln", log @},
+ @{ "sin", sin @},
+ @{ "sqrt", sqrt @},
+ @{ 0, 0 @},
@};
@end group
@group
/* Put arithmetic functions in table. */
+static
void
init_table (void)
@{
@}
@}
@end group
-
-@group
-int
-main (void)
-@{
- init_table ();
- return yyparse ();
-@}
-@end group
@end example
By simply editing the initialization list and adding the necessary include
symrec *ptr;
for (ptr = sym_table; ptr != (symrec *) 0;
ptr = (symrec *)ptr->next)
- if (strcmp (ptr->name,sym_name) == 0)
+ if (strcmp (ptr->name, sym_name) == 0)
return ptr;
return 0;
@}
@end group
@end example
+@node Mfcalc Lexer
+@subsection The @code{mfcalc} Lexer
+
The function @code{yylex} must now recognize variables, numeric values, and
the single-character arithmetic operators. Strings of alphanumeric
characters with a leading letter are recognized as either variables or
@comment file: mfcalc.y: 3
@example
-@group
#include <ctype.h>
-@end group
@group
int
symrec *s;
int i;
@end group
-
if (!symbuf)
symbuf = (char *) malloc (length + 1);
@end group
@end example
+@node Mfcalc Main
+@subsection The @code{mfcalc} Main
+
The error reporting function is unchanged, and the new version of
@code{main} includes a call to @code{init_table} and sets the @code{yydebug}
on user demand (@xref{Tracing, , Tracing Your Parser}, for details):
@node Grammar Outline
@section Outline of a Bison Grammar
+ @cindex comment
+ @findex // @dots{}
+ @findex /* @dots{} */
A Bison grammar file has four main sections, shown here with the
appropriate delimiters:
@end example
Comments enclosed in @samp{/* @dots{} */} may appear in any of the sections.
- As a GNU extension, @samp{//} introduces a comment that
- continues until end of line.
+ As a GNU extension, @samp{//} introduces a comment that continues until end
+ of line.
@menu
* Prologue:: Syntax and usage of the prologue.
A Bison grammar rule has the following general form:
@example
-@group
@var{result}: @var{components}@dots{};
-@end group
@end example
@noindent
For example,
@example
-@group
exp: exp '+' exp;
-@end group
@end example
@noindent
following example, the action is triggered only when @samp{b} is found:
@example
-@group
a-or-b: 'a'|'b' @{ a_or_b_found = 1; @};
-@end group
@end example
@cindex default action
These actions are written just like usual end-of-rule actions, but they
are executed before the parser even recognizes the following components.
+ @menu
+ * Using Mid-Rule Actions:: Putting an action in the middle of a rule.
+ * Mid-Rule Action Translation:: How mid-rule actions are actually processed.
+ * Mid-Rule Conflicts:: Mid-rule actions can cause conflicts.
+ @end menu
+
+ @node Using Mid-Rule Actions
+ @subsubsection Using Mid-Rule Actions
+
A mid-rule action may refer to the components preceding it using
@code{$@var{n}}, but it may not refer to subsequent components because
it is run before they are parsed.
@example
@group
stmt:
- LET '(' var ')'
- @{ $<context>$ = push_context (); declare_variable ($3); @}
+ "let" '(' var ')'
+ @{
+ $<context>$ = push_context ();
+ declare_variable ($3);
+ @}
stmt
- @{ $$ = $6; pop_context ($<context>5); @}
+ @{
+ $$ = $6;
+ pop_context ($<context>5);
+ @}
@end group
@end example
@code{context} in the data-type union. Then it calls
@code{declare_variable} to add the new variable to that list. Once the
first action is finished, the embedded statement @code{stmt} can be
- parsed. Note that the mid-rule action is component number 5, so the
- @samp{stmt} is component number 6.
+ parsed.
+
+ Note that the mid-rule action is component number 5, so the @samp{stmt} is
+ component number 6. Named references can be used to improve the readability
+ and maintainability (@pxref{Named References}):
+
+ @example
+ @group
+ stmt:
+ "let" '(' var ')'
+ @{
+ $<context>let = push_context ();
+ declare_variable ($3);
+ @}[let]
+ stmt
+ @{
+ $$ = $6;
+ pop_context ($<context>let);
+ @}
+ @end group
+ @end example
After the embedded statement is parsed, its semantic value becomes the
value of the entire @code{let}-statement. Then the semantic value from the
let stmt
@{
$$ = $2;
- pop_context ($1);
+ pop_context ($let);
@};
let:
- LET '(' var ')'
+ "let" '(' var ')'
@{
- $$ = push_context ();
+ $let = push_context ();
declare_variable ($3);
@};
Any mid-rule action can be converted to an end-of-rule action in this way, and
this is what Bison actually does to implement mid-rule actions.
+ @node Mid-Rule Action Translation
+ @subsubsection Mid-Rule Action Translation
+ @vindex $@@@var{n}
+ @vindex @@@var{n}
+
+ As hinted earlier, mid-rule actions are actually transformed into regular
+ rules and actions. The various reports generated by Bison (textual,
+ graphical, etc., see @ref{Understanding, , Understanding Your Parser})
+ reveal this translation, best explained by means of an example. The
+ following rule:
+
+ @example
+ exp: @{ a(); @} "b" @{ c(); @} @{ d(); @} "e" @{ f(); @};
+ @end example
+
+ @noindent
+ is translated into:
+
+ @example
+ $@@1: /* empty */ @{ a(); @};
+ $@@2: /* empty */ @{ c(); @};
+ $@@3: /* empty */ @{ d(); @};
+ exp: $@@1 "b" $@@2 $@@3 "e" @{ f(); @};
+ @end example
+
+ @noindent
+ with new nonterminal symbols @code{$@@@var{n}}, where @var{n} is a number.
+
+ A mid-rule action is expected to generate a value if it uses @code{$$}, or
+ the (final) action uses @code{$@var{n}} where @var{n} denote the mid-rule
+ action. In that case its nonterminal is rather named @code{@@@var{n}}:
+
+ @example
+ exp: @{ a(); @} "b" @{ $$ = c(); @} @{ d(); @} "e" @{ f = $1; @};
+ @end example
+
+ @noindent
+ is translated into
+
+ @example
+ @@1: /* empty */ @{ a(); @};
+ @@2: /* empty */ @{ $$ = c(); @};
+ $@@3: /* empty */ @{ d(); @};
+ exp: @@1 "b" @@2 $@@3 "e" @{ f = $1; @}
+ @end example
+
+ There are probably two errors in the above example: the first mid-rule
+ action does not generate a value (it does not use @code{$$} although the
+ final action uses it), and the value of the second one is not used (the
+ final action does not use @code{$3}). Bison reports these errors when the
+ @code{midrule-value} warnings are enabled (@pxref{Invocation, ,Invoking
+ Bison}):
+
+ @example
+ $ bison -fcaret -Wmidrule-value mid.y
+ @group
+ mid.y:2.6-13: warning: unset value: $$
+ exp: @{ a(); @} "b" @{ $$ = c(); @} @{ d(); @} "e" @{ f = $1; @};
+ ^^^^^^^^
+ @end group
+ @group
+ mid.y:2.19-31: warning: unused value: $3
+ exp: @{ a(); @} "b" @{ $$ = c(); @} @{ d(); @} "e" @{ f = $1; @};
+ ^^^^^^^^^^^^^
+ @end group
+ @end example
+
+
+ @node Mid-Rule Conflicts
+ @subsubsection Conflicts due to Mid-Rule Actions
Taking action before a rule is completely recognized often leads to
conflicts since the parser must commit to a parse in order to execute the
action. For example, the following two rules, without mid-rule actions,
Now Bison can execute the action in the rule for @code{subroutine} without
deciding which rule for @code{compound} it will eventually use.
+
@node Tracking Locations
@section Tracking Locations
@cindex location
the parser, so that the function @code{yylex} (if it is in this file)
can use the name @var{name} to stand for this token type's code.
-Alternatively, you can use @code{%left}, @code{%right}, or
+Alternatively, you can use @code{%left}, @code{%right},
+@code{%precedence}, or
@code{%nonassoc} instead of @code{%token}, if you wish to specify
associativity and precedence. @xref{Precedence Decl, ,Operator
Precedence}.
@cindex declaring operator precedence
@cindex operator precedence, declaring
-Use the @code{%left}, @code{%right} or @code{%nonassoc} declaration to
+Use the @code{%left}, @code{%right}, @code{%nonassoc}, or
+@code{%precedence} declaration to
declare a token and specify its precedence and associativity, all at
once. These are called @dfn{precedence declarations}.
@xref{Precedence, ,Operator Precedence}, for general information on
means that @samp{@var{x} @var{op} @var{y} @var{op} @var{z}} is
considered a syntax error.
+@code{%precedence} gives only precedence to the @var{symbols}, and
+defines no associativity at all. Use this to define precedence only,
+and leave any potential conflict due to associativity enabled.
+
@item
The precedence of an operator determines how it nests with other operators.
All the tokens declared in a single precedence declaration have equal
including @code{yylval} and @code{yylloc}.)
Alternatively, you can generate a pure, reentrant parser. The Bison
-declaration @code{%define api.pure} says that you want the parser to be
+declaration @samp{%define api.pure} says that you want the parser to be
reentrant. It looks like this:
@example
Bison also supports both the push parser interface along with the pull parser
interface in the same generated parser. In order to get this functionality,
-you should replace the @code{%define api.push-pull push} declaration with the
-@code{%define api.push-pull both} declaration. Doing this will create all of
+you should replace the @samp{%define api.push-pull push} declaration with the
+@samp{%define api.push-pull both} declaration. Doing this will create all of
the symbols mentioned earlier along with the two extra symbols, @code{yyparse}
and @code{yypull_parse}. @code{yyparse} can be used exactly as it normally
would be used. However, the user should note that it is implemented in the
generated parser by calling @code{yypull_parse}.
This makes the @code{yyparse} function that is generated with the
-@code{%define api.push-pull both} declaration slower than the normal
+@samp{%define api.push-pull both} declaration slower than the normal
@code{yyparse} function. If the user
calls the @code{yypull_parse} function it will parse the rest of the input
stream. It is possible to @code{yypush_parse} tokens to select a subgrammar
yypstate_delete (ps);
@end example
-Adding the @code{%define api.pure full} declaration does exactly the same thing
-to the generated parser with @code{%define api.push-pull both} as it did for
-@code{%define api.push-pull push}.
+Adding the @samp{%define api.pure} declaration does exactly the same thing to
+the generated parser with @samp{%define api.push-pull both} as it did for
+@samp{%define api.push-pull push}.
@node Decl Summary
@subsection Bison Declaration Summary
@end deffn
@deffn {Directive} %debug
-In the parser implementation file, define the macro @code{YYDEBUG} (or
-@code{@var{prefix}DEBUG} with @samp{%define api.prefix @var{prefix}}, see
-@ref{Multiple Parsers, ,Multiple Parsers in the Same Program}) to 1 if it is
-not already defined, so that the debugging facilities are compiled.
+Instrument the parser for traces. Obsoleted by @samp{%define
+parse.trace}.
@xref{Tracing, ,Tracing Your Parser}.
@end deffn
accurate syntax error messages.
@end deffn
+@deffn {Directive} %name-prefix "@var{prefix}"
+Rename the external symbols used in the parser so that they start with
+@var{prefix} instead of @samp{yy}. The precise list of symbols renamed
+in C parsers
+is @code{yyparse}, @code{yylex}, @code{yyerror}, @code{yynerrs},
+@code{yylval}, @code{yychar}, @code{yydebug}, and
+(if locations are used) @code{yylloc}. If you use a push parser,
+@code{yypush_parse}, @code{yypull_parse}, @code{yypstate},
+@code{yypstate_new} and @code{yypstate_delete} will
+also be renamed. For example, if you use @samp{%name-prefix "c_"}, the
+names become @code{c_parse}, @code{c_lex}, and so on.
+For C++ parsers, see the @samp{%define api.namespace} documentation in this
+section.
+@xref{Multiple Parsers, ,Multiple Parsers in the Same Program}.
+@end deffn
+
@ifset defaultprec
@deffn {Directive} %no-default-prec
Do not assign a precedence to rules lacking an explicit @code{%prec}
@end deffn
@deffn {Directive} %pure-parser
-Deprecated version of @code{%define api.pure} (@pxref{%define
+Deprecated version of @samp{%define api.pure} (@pxref{%define
Summary,,api.pure}), for which Bison is more careful to warn about
unreasonable usage.
@end deffn
Unaccepted @var{variable}s produce an error.
Some of the accepted @var{variable}s are:
-@itemize @bullet
+@table @code
+@c ================================================== api.namespace
+@item api.namespace
+@findex %define api.namespace
+@itemize
+@item Languages(s): C++
+
+@item Purpose: Specify the namespace for the parser class.
+For example, if you specify:
+
+@example
+%define api.namespace "foo::bar"
+@end example
+
+Bison uses @code{foo::bar} verbatim in references such as:
+
+@example
+foo::bar::parser::semantic_type
+@end example
+
+However, to open a namespace, Bison removes any leading @code{::} and then
+splits on any remaining occurrences:
+
+@example
+namespace foo @{ namespace bar @{
+ class position;
+ class location;
+@} @}
+@end example
+
+@item Accepted Values:
+Any absolute or relative C++ namespace reference without a trailing
+@code{"::"}. For example, @code{"foo"} or @code{"::foo::bar"}.
+
+@item Default Value:
+The value specified by @code{%name-prefix}, which defaults to @code{yy}.
+This usage of @code{%name-prefix} is for backward compatibility and can
+be confusing since @code{%name-prefix} also specifies the textual prefix
+for the lexical analyzer function. Thus, if you specify
+@code{%name-prefix}, it is best to also specify @samp{%define
+api.namespace} so that @code{%name-prefix} @emph{only} affects the
+lexical analyzer function. For example, if you specify:
+
+@example
+%define api.namespace "foo"
+%name-prefix "bar::"
+@end example
+
+The parser namespace is @code{foo} and @code{yylex} is referenced as
+@code{bar::lex}.
+@end itemize
+@c namespace
+
@c ================================================== api.location.type
@item @code{api.location.type}
@findex %define api.location.type
@end itemize
@c ================================================== api.prefix
-@item @code{api.prefix}
+@item api.prefix
@findex %define api.prefix
@itemize @bullet
@end itemize
@c ================================================== api.pure
-@item @code{api.pure}
+@item api.pure
@findex %define api.pure
@itemize @bullet
@code{yyerror} are:
@example
- void yyerror (char const *msg); /* Yacc parsers. */
- void yyerror (YYLTYPE *locp, char const *msg); /* GLR parsers. */
+ void yyerror (char const *msg); // Yacc parsers.
+ void yyerror (YYLTYPE *locp, char const *msg); // GLR parsers.
@end example
But if @samp{%locations %define api.pure %parse-param @{int *nastiness@}} is
@item History: the @code{full} value was introduced in Bison 2.7
@end itemize
+@c api.pure
-@c ================================================== api.push-pull
-@item @code{api.push-pull}
+
+@c ================================================== api.push-pull
+@item api.push-pull
@findex %define api.push-pull
@itemize @bullet
@item Default Value: @code{pull}
@end itemize
+@c api.push-pull
+
-@c ================================================== lr.default-reductions
-@item @code{lr.default-reductions}
-@findex %define lr.default-reductions
+@c ================================================== api.token.constructor
+@item api.token.constructor
+@findex %define api.token.constructor
+
+@itemize @bullet
+@item Language(s):
+C++
+
+@item Purpose:
+When variant-based semantic values are enabled (@pxref{C++ Variants}),
+request that symbols be handled as a whole (type, value, and possibly
+location) in the scanner. @xref{Complete Symbols}, for details.
+
+@item Accepted Values:
+Boolean.
+
+@item Default Value:
+@code{false}
+@item History:
+introduced in Bison 2.8
+@end itemize
+@c api.token.constructor
+
+
+@c ================================================== api.token.prefix
+@item api.token.prefix
+@findex %define api.token.prefix
+
+@itemize
+@item Languages(s): all
+
+@item Purpose:
+Add a prefix to the token names when generating their definition in the
+target language. For instance
+
+@example
+%token FILE for ERROR
+%define api.token.prefix "TOK_"
+%%
+start: FILE for ERROR;
+@end example
+
+@noindent
+generates the definition of the symbols @code{TOK_FILE}, @code{TOK_for},
+and @code{TOK_ERROR} in the generated source files. In particular, the
+scanner must use these prefixed token names, while the grammar itself
+may still use the short names (as in the sample rule given above). The
+generated informational files (@file{*.output}, @file{*.xml},
+@file{*.dot}) are not modified by this prefix. See @ref{Calc++ Parser}
+and @ref{Calc++ Scanner}, for a complete example.
+
+@item Accepted Values:
+Any string. Should be a valid identifier prefix in the target language,
+in other words, it should typically be an identifier itself (sequence of
+letters, underscores, and ---not at the beginning--- digits).
+
+@item Default Value:
+empty
+@item History:
+introduced in Bison 2.8
+@end itemize
+@c api.token.prefix
+
+
+@c ================================================== lr.default-reduction
+
+@item lr.default-reduction
+@findex %define lr.default-reduction
@itemize @bullet
@item Language(s): all
@item @code{accepting} if @code{lr.type} is @code{canonical-lr}.
@item @code{most} otherwise.
@end itemize
+@item History:
+introduced as @code{lr.default-reduction} in 2.5, renamed as
+@code{lr.default-reduction} in 2.8.
@end itemize
-@c ============================================ lr.keep-unreachable-states
+@c ============================================ lr.keep-unreachable-state
-@item @code{lr.keep-unreachable-states}
-@findex %define lr.keep-unreachable-states
+@item lr.keep-unreachable-state
+@findex %define lr.keep-unreachable-state
@itemize @bullet
@item Language(s): all
@item Accepted Values: Boolean
@item Default Value: @code{false}
@end itemize
+introduced as @code{lr.keep_unreachable_states} in 2.3b, renamed as
+@code{lr.keep-unreachable-states} in 2.5, and as
+@code{lr.keep-unreachable-state} in 2.8.
+@c lr.keep-unreachable-state
@c ================================================== lr.type
-@item @code{lr.type}
+@item lr.type
@findex %define lr.type
@itemize @bullet
@item Default Value: @code{lalr}
@end itemize
-@c ================================================== namespace
-@item @code{namespace}
+@c ================================================== namespace
+@item namespace
@findex %define namespace
+Obsoleted by @code{api.namespace}
+@c namespace
-@itemize
-@item Languages(s): C++
-@item Purpose: Specify the namespace for the parser class.
-For example, if you specify:
+@c ================================================== parse.assert
+@item parse.assert
+@findex %define parse.assert
-@smallexample
-%define namespace "foo::bar"
-@end smallexample
+@itemize
+@item Languages(s): C++
-Bison uses @code{foo::bar} verbatim in references such as:
+@item Purpose: Issue runtime assertions to catch invalid uses.
+In C++, when variants are used (@pxref{C++ Variants}), symbols must be
+constructed and
+destroyed properly. This option checks these constraints.
-@smallexample
-foo::bar::parser::semantic_type
-@end smallexample
+@item Accepted Values: Boolean
-However, to open a namespace, Bison removes any leading @code{::} and then
-splits on any remaining occurrences:
+@item Default Value: @code{false}
+@end itemize
+@c parse.assert
-@smallexample
-namespace foo @{ namespace bar @{
- class position;
- class location;
-@} @}
-@end smallexample
-
-@item Accepted Values: Any absolute or relative C++ namespace reference without
-a trailing @code{"::"}.
-For example, @code{"foo"} or @code{"::foo::bar"}.
-
-@item Default Value: The value specified by @code{%name-prefix}, which defaults
-to @code{yy}.
-This usage of @code{%name-prefix} is for backward compatibility and can be
-confusing since @code{%name-prefix} also specifies the textual prefix for the
-lexical analyzer function.
-Thus, if you specify @code{%name-prefix}, it is best to also specify
-@code{%define namespace} so that @code{%name-prefix} @emph{only} affects the
-lexical analyzer function.
-For example, if you specify:
-@smallexample
-%define namespace "foo"
-%name-prefix "bar::"
-@end smallexample
+@c ================================================== parse.error
+@item parse.error
+@findex %define parse.error
+@itemize
+@item Languages(s):
+all
+@item Purpose:
+Control the kind of error messages passed to the error reporting
+function. @xref{Error Reporting, ,The Error Reporting Function
+@code{yyerror}}.
+@item Accepted Values:
+@itemize
+@item @code{simple}
+Error messages passed to @code{yyerror} are simply @w{@code{"syntax
+error"}}.
+@item @code{verbose}
+Error messages report the unexpected token, and possibly the expected ones.
+However, this report can often be incorrect when LAC is not enabled
+(@pxref{LAC}).
+@end itemize
-The parser namespace is @code{foo} and @code{yylex} is referenced as
-@code{bar::lex}.
+@item Default Value:
+@code{simple}
@end itemize
+@c parse.error
+
@c ================================================== parse.lac
-@item @code{parse.lac}
+@item parse.lac
@findex %define parse.lac
@itemize
@item Accepted Values: @code{none}, @code{full}
@item Default Value: @code{none}
@end itemize
+@c parse.lac
+
+@c ================================================== parse.trace
+@item parse.trace
+@findex %define parse.trace
+
+@itemize
+@item Languages(s): C, C++, Java
+
+@item Purpose: Require parser instrumentation for tracing.
+@xref{Tracing, ,Tracing Your Parser}.
+
+In C/C++, define the macro @code{YYDEBUG} (or @code{@var{prefix}DEBUG} with
+@samp{%define api.prefix @var{prefix}}), see @ref{Multiple Parsers,
+,Multiple Parsers in the Same Program}) to 1 in the parser implementation
+file if it is not already defined, so that the debugging facilities are
+compiled.
+
+@item Accepted Values: Boolean
+
+@item Default Value: @code{false}
+@end itemize
+@c parse.trace
+
+@c ================================================== variant
+@item variant
+@findex %define variant
+
+@itemize @bullet
+@item Language(s):
+C++
+
+@item Purpose:
+Request variant-based semantic values.
+@xref{C++ Variants}.
+
+@item Accepted Values:
+Boolean.
+
+@item Default Value:
+@code{false}
@end itemize
+@c variant
+@end table
@node %code Summary
Not all qualifiers are accepted for all target languages. Unaccepted
qualifiers produce an error. Some of the accepted qualifiers are:
-@itemize @bullet
+@table @code
@item requires
@findex %code requires
@item Location(s): The parser Java file after any Java package directive and
before any class definitions.
@end itemize
-@end itemize
+@end table
Though we say the insertion locations are language-dependent, they are
technically skeleton-dependent. Writers of non-standard skeletons
parameter information to it in a reentrant way. To do so, use the
declaration @code{%parse-param}:
-@deffn {Directive} %parse-param @{@var{argument-declaration}@}
+@deffn {Directive} %parse-param @{@var{argument-declaration}@} @dots{}
@findex %parse-param
-Declare that an argument declared by the braced-code
-@var{argument-declaration} is an additional @code{yyparse} argument.
+Declare that one or more
+@var{argument-declaration} are additional @code{yyparse} arguments.
The @var{argument-declaration} is used when declaring
functions or prototypes. The last identifier in
@var{argument-declaration} must be the argument name.
Here's an example. Write this in the parser:
@example
-%parse-param @{int *nastiness@}
-%parse-param @{int *randomness@}
+%parse-param @{int *nastiness@} @{int *randomness@}
@end example
@noindent
More user feedback will help to stabilize it.)
You call the function @code{yypush_parse} to parse a single token. This
-function is available if either the @code{%define api.push-pull push} or
-@code{%define api.push-pull both} declaration is used.
+function is available if either the @samp{%define api.push-pull push} or
+@samp{%define api.push-pull both} declaration is used.
@xref{Push Decl, ,A Push Parser}.
@deftypefun int yypush_parse (yypstate *yyps)
More user feedback will help to stabilize it.)
You call the function @code{yypull_parse} to parse the rest of the input
-stream. This function is available if the @code{%define api.push-pull both}
+stream. This function is available if the @samp{%define api.push-pull both}
declaration is used.
@xref{Push Decl, ,A Push Parser}.
More user feedback will help to stabilize it.)
You call the function @code{yypstate_new} to create a new parser instance.
-This function is available if either the @code{%define api.push-pull push} or
-@code{%define api.push-pull both} declaration is used.
+This function is available if either the @samp{%define api.push-pull push} or
+@samp{%define api.push-pull both} declaration is used.
@xref{Push Decl, ,A Push Parser}.
@deftypefun {yypstate*} yypstate_new (void)
More user feedback will help to stabilize it.)
You call the function @code{yypstate_delete} to delete a parser instance.
-function is available if either the @code{%define api.push-pull push} or
-@code{%define api.push-pull both} declaration is used.
+function is available if either the @samp{%define api.push-pull push} or
+@samp{%define api.push-pull both} declaration is used.
@xref{Push Decl, ,A Push Parser}.
@deftypefun void yypstate_delete (yypstate *yyps)
this case, omit the second argument; @code{yylex} will be called with
only one argument.
-
-If you wish to pass the additional parameter data to @code{yylex}, use
+If you wish to pass additional arguments to @code{yylex}, use
@code{%lex-param} just like @code{%parse-param} (@pxref{Parser
-Function}).
+Function}). To pass additional arguments to both @code{yylex} and
+@code{yyparse}, use @code{%param}.
-@deffn {Directive} lex-param @{@var{argument-declaration}@}
+@deffn {Directive} %lex-param @{@var{argument-declaration}@} @dots{}
@findex %lex-param
-Declare that the braced-code @var{argument-declaration} is an
-additional @code{yylex} argument declaration.
+Specify that @var{argument-declaration} are additional @code{yylex} argument
+declarations. You may pass one or more such declarations, which is
+equivalent to repeating @code{%lex-param}.
+@end deffn
+
+@deffn {Directive} %param @{@var{argument-declaration}@} @dots{}
+@findex %param
+Specify that @var{argument-declaration} are additional
+@code{yylex}/@code{yyparse} argument declaration. This is equivalent to
+@samp{%lex-param @{@var{argument-declaration}@} @dots{} %parse-param
+@{@var{argument-declaration}@} @dots{}}. You may pass one or more
+declarations, which is equivalent to repeating @code{%param}.
@end deffn
@noindent
For instance:
@example
-%lex-param @{int *nastiness@}
+%lex-param @{scanner_mode *mode@}
+%parse-param @{parser_mode *mode@}
+%param @{environment_type *env@}
@end example
@noindent
-results in the following signature:
+results in the following signatures:
@example
-int yylex (int *nastiness);
+int yylex (scanner_mode *mode, environment_type *env);
+int yyparse (parser_mode *mode, environment_type *env);
+@end example
+
+If @samp{%define api.pure full} is added:
+
+@example
+int yylex (YYSTYPE *lvalp, scanner_mode *mode, environment_type *env);
+int yyparse (parser_mode *mode, environment_type *env);
@end example
@noindent
-If @code{%define api.pure full} (or just @code{%define api.pure}) is added:
+and finally, if both @samp{%define api.pure full} and @code{%locations} are
+used:
@example
-int yylex (YYSTYPE *lvalp, int *nastiness);
+int yylex (YYSTYPE *lvalp, YYLTYPE *llocp,
+ scanner_mode *mode, environment_type *env);
+int yyparse (parser_mode *mode, environment_type *env);
@end example
@node Error Reporting
@cindex parse error
@cindex syntax error
-The Bison parser detects a @dfn{syntax error} or @dfn{parse error}
+The Bison parser detects a @dfn{syntax error} (or @dfn{parse error})
whenever it reads a token which cannot satisfy any syntax rule. An
action in the grammar can also explicitly proclaim an error, using the
macro @code{YYERROR} (@pxref{Action Features, ,Special Features for Use
receives one argument. For a syntax error, the string is normally
@w{@code{"syntax error"}}.
-@findex %error-verbose
-If you invoke the directive @code{%error-verbose} in the Bison declarations
+@findex %define parse.error
+If you invoke @samp{%define parse.error verbose} in the Bison declarations
section (@pxref{Bison Declarations, ,The Bison Declarations Section}), then
Bison provides a more verbose and specific error message string instead of
just plain @w{@code{"syntax error"}}. However, that message sometimes
@end deffn
@deffn {Value} @@$
- @findex @@$
Acts like a structure variable containing information on the textual
location of the grouping made by the current rule. @xref{Tracking
Locations}.
@item
@cindex bison-i18n.m4
Into the directory containing the GNU Autoconf macros used
- by the package---often called @file{m4}---copy the
+ by the package ---often called @file{m4}--- copy the
@file{bison-i18n.m4} file installed by Bison under
@samp{share/aclocal/bison-i18n.m4} in Bison's installation directory.
For example:
the conflict:
@example
-@group
%%
-@end group
@group
stmt:
expr
@menu
* Why Precedence:: An example showing why precedence is needed.
-* Using Precedence:: How to specify precedence in Bison grammars.
+* Using Precedence:: How to specify precedence and associativity.
+* Precedence Only:: How to specify precedence only.
* Precedence Examples:: How these features are used in the previous example.
* How Precedence:: How they work.
* Non Operators:: Using precedence for general conflicts.
@node Using Precedence
@subsection Specifying Operator Precedence
@findex %left
-@findex %right
@findex %nonassoc
+@findex %precedence
+@findex %right
Bison allows you to specify these choices with the operator precedence
declarations @code{%left} and @code{%right}. Each such declaration
them right-associative. A third alternative is @code{%nonassoc}, which
declares that it is a syntax error to find the same operator twice ``in a
row''.
+The last alternative, @code{%precedence}, allows to define only
+precedence and no associativity at all. As a result, any
+associativity-related conflict that remains will be reported as an
+compile-time error. The directive @code{%nonassoc} creates run-time
+error: using the operator in a associative way is a syntax error. The
+directive @code{%precedence} creates compile-time errors: an operator
+@emph{can} be involved in an associativity-related conflict, contrary to
+what expected the grammar author.
The relative precedence of different operators is controlled by the
-order in which they are declared. The first @code{%left} or
-@code{%right} declaration in the file declares the operators whose
+order in which they are declared. The first precedence/associativity
+declaration in the file declares the operators whose
precedence is lowest, the next such declaration declares the operators
whose precedence is a little higher, and so on.
+@node Precedence Only
+@subsection Specifying Precedence Only
+@findex %precedence
+
+Since POSIX Yacc defines only @code{%left}, @code{%right}, and
+@code{%nonassoc}, which all defines precedence and associativity, little
+attention is paid to the fact that precedence cannot be defined without
+defining associativity. Yet, sometimes, when trying to solve a
+conflict, precedence suffices. In such a case, using @code{%left},
+@code{%right}, or @code{%nonassoc} might hide future (associativity
+related) conflicts that would remain hidden.
+
+The dangling @code{else} ambiguity (@pxref{Shift/Reduce, , Shift/Reduce
+Conflicts}) can be solved explicitly. This shift/reduce conflicts occurs
+in the following situation, where the period denotes the current parsing
+state:
+
+@example
+if @var{e1} then if @var{e2} then @var{s1} . else @var{s2}
+@end example
+
+The conflict involves the reduction of the rule @samp{IF expr THEN
+stmt}, which precedence is by default that of its last token
+(@code{THEN}), and the shifting of the token @code{ELSE}. The usual
+disambiguation (attach the @code{else} to the closest @code{if}),
+shifting must be preferred, i.e., the precedence of @code{ELSE} must be
+higher than that of @code{THEN}. But neither is expected to be involved
+in an associativity related conflict, which can be specified as follows.
+
+@example
+%precedence THEN
+%precedence ELSE
+@end example
+
+The unary-minus is another typical example where associativity is
+usually over-specified, see @ref{Infix Calc, , Infix Notation
+Calculator: @code{calc}}. The @code{%left} directive is traditionally
+used to declare the precedence of @code{NEG}, which is more than needed
+since it also defines its associativity. While this is harmless in the
+traditional example, who knows how @code{NEG} might be used in future
+evolutions of the grammar@dots{}
+
@node Precedence Examples
@subsection Precedence Examples
@example
@group
-%nonassoc "then"
-%nonassoc "else"
+%precedence "then"
+%precedence "else"
@end group
@end example
@end example
Neither solution is perfect however. Since Bison does not provide, so far,
-support for ``scoped'' precedence, both force you to declare the precedence
+``scoped'' precedence, both force you to declare the precedence
of these keywords with respect to the other operators your grammar.
Therefore, instead of being warned about new conflicts you would be unaware
of (e.g., a shift/reduce conflict due to @samp{if test then 1 else 2 + 3}
sign typically has a very high precedence as a unary operator, and a
somewhat lower precedence (lower than multiplication) as a binary operator.
-The Bison precedence declarations, @code{%left}, @code{%right} and
-@code{%nonassoc}, can only be used once for a given token; so a token has
+The Bison precedence declarations
+can only be used once for a given token; so a token has
only one precedence declared in this way. For context-dependent
precedence, you need to use an additional mechanism: the @code{%prec}
modifier for rules.
Here is another common error that yields a reduce/reduce conflict:
@example
-sequence:
@group
+sequence:
/* empty */
| sequence words
| sequence redirects
rule:
@example
-%nonassoc "word"
-%nonassoc "sequence"
+%precedence "word"
+%precedence "sequence"
%%
@group
sequence:
| name_list ':' type
;
@end group
+
@group
return_spec:
type
| name ':' type
;
@end group
-@group
+
type: "id";
-@end group
+
@group
name: "id";
name_list:
rather than the one for @code{name}.
@example
+@group
param_spec:
type
| name_list ':' type
;
+@end group
+
+@group
return_spec:
type
| "id" ':' type
;
+@end group
@end example
For a more detailed exposition of LALR(1) parsers and parser
historical reasons, but that behavior is often not robust. For example, in
the previous section, we discussed the mysterious conflicts that can be
produced by LALR(1), Bison's default parser table construction algorithm.
-Another example is Bison's @code{%error-verbose} directive, which instructs
-the generated parser to produce verbose syntax error messages, which can
-sometimes contain incorrect information.
+Another example is Bison's @code{%define parse.error verbose} directive,
+which instructs the generated parser to produce verbose syntax error
+messages, which can sometimes contain incorrect information.
In this section, we explore several modern features of Bison that allow you
to tune fundamental aspects of the generated LR-based parsers. Some of
@cindex GLR with LALR
When employing GLR parsers (@pxref{GLR Parsers}), if you do not resolve any
-conflicts statically (for example, with @code{%left} or @code{%prec}), then
+conflicts statically (for example, with @code{%left} or @code{%precedence}),
+then
the parser explores all potential parses of any given input. In this case,
the choice of parser table construction algorithm is guaranteed not to alter
the language accepted by the parser. LALR parser tables are the smallest
@node Default Reductions
@subsection Default Reductions
@cindex default reductions
-@findex %define lr.default-reductions
+@findex %define lr.default-reduction
@findex %nonassoc
After parser table construction, Bison identifies the reduction with the
split the parse instead.
To adjust which states have default reductions enabled, use the
-@code{%define lr.default-reductions} directive.
+@code{%define lr.default-reduction} directive.
-@deffn {Directive} {%define lr.default-reductions} @var{where}
+@deffn {Directive} {%define lr.default-reduction} @var{where}
Specify the kind of states that are permitted to contain default reductions.
The accepted values of @var{where} are:
@itemize
@node Unreachable States
@subsection Unreachable States
-@findex %define lr.keep-unreachable-states
+@findex %define lr.keep-unreachable-state
@cindex unreachable states
If there exists no sequence of transitions from the parser's start state to
keeping unreachable states is sometimes useful when trying to understand the
relationship between the parser and the grammar.
-@deffn {Directive} {%define lr.keep-unreachable-states} @var{value}
+@deffn {Directive} {%define lr.keep-unreachable-state} @var{value}
Request that Bison allow unreachable states to remain in the parser tables.
@var{value} must be a Boolean. The default is @code{false}.
@end deffn
Do not allow @code{YYINITDEPTH} to be greater than @code{YYMAXDEPTH}.
-@c FIXME: C++ output.
-Because of semantic differences between C and C++, the deterministic
-parsers in C produced by Bison cannot grow when compiled
-by C++ compilers. In this precise case (compiling a C parser as C++) you are
-suggested to grow @code{YYINITDEPTH}. The Bison maintainers hope to fix
-this deficiency in a future release.
+You can generate a deterministic parser containing C++ user code from
+the default (C) skeleton, as well as from the C++ skeleton
+(@pxref{C++ Parsers}). However, if you do use the default skeleton
+and want to allow the parsing stack to grow,
+be careful not to use semantic types or location types that require
+non-trivial copy constructors.
+The C skeleton bypasses these constructors when copying data to
+new, larger stacks.
@node Error Recovery
@chapter Error Recovery
Developing a parser can be a challenge, especially if you don't understand
the algorithm (@pxref{Algorithm, ,The Bison Parser Algorithm}). This
- chapter explains how to generate and read the detailed description of the
- automaton, and how to enable and understand the parser run-time traces.
+ chapter explains how understand and debug a parser.
+
+ The first sections focus on the static part of the parser: its structure.
+ They explain how to generate and read the detailed description of the
+ automaton. There are several formats available:
+ @itemize @minus
+ @item
+ as text, see @ref{Understanding, , Understanding Your Parser};
+
+ @item
+ as a graph, see @ref{Graphviz,, Visualizing Your Parser};
+
+ @item
+ or as a markup report that can be turned, for instance, into HTML, see
+ @ref{Xml,, Visualizing your parser in multiple formats}.
+ @end itemize
+
+ The last section focuses on the dynamic part of the parser: how to enable
+ and understand the parser run-time traces (@pxref{Tracing, ,Tracing Your
+ Parser}).
@menu
* Understanding:: Understanding the structure of your parser.
As documented elsewhere (@pxref{Algorithm, ,The Bison Parser Algorithm})
Bison parsers are @dfn{shift/reduce automata}. In some cases (much more
frequent than one would hope), looking at this automaton is required to
- tune or simply fix a parser. Bison provides two different
- representation of it, either textually or graphically (as a DOT file).
+ tune or simply fix a parser.
The textual file is generated when the options @option{--report} or
@option{--verbose} are specified, see @ref{Invocation, , Invoking
@example
%token NUM STR
+ @group
%left '+' '-'
%left '*'
+ @end group
%%
+ @group
exp:
exp '+' exp
| exp '-' exp
| exp '/' exp
| NUM
;
+ @end group
useless: STR;
%%
@end example
@example
calc.y: warning: 1 nonterminal useless in grammar
calc.y: warning: 1 rule useless in grammar
- calc.y:11.1-7: warning: nonterminal useless in grammar: useless
- calc.y:11.10-12: warning: rule useless in grammar: useless: STR
+ calc.y:12.1-7: warning: nonterminal useless in grammar: useless
+ calc.y:12.10-12: warning: rule useless in grammar: useless: STR
calc.y: conflicts: 7 shift/reduce
@end example
the location of the input cursor.
@example
- state 0
+ State 0
0 $accept: . exp $end
@option{--report=itemset} to list the derived items as well:
@example
- state 0
+ State 0
0 $accept: . exp $end
1 exp: . exp '+' exp
In the state 1@dots{}
@example
- state 1
+ State 1
5 exp: NUM .
@noindent
the rule 5, @samp{exp: NUM;}, is completed. Whatever the lookahead token
(@samp{$default}), the parser will reduce it. If it was coming from
- state 0, then, after this reduction it will return to state 0, and will
+ State 0, then, after this reduction it will return to state 0, and will
jump to state 2 (@samp{exp: go to state 2}).
@example
- state 2
+ State 2
0 $accept: exp . $end
1 exp: exp . '+' exp
state}:
@example
- state 3
+ State 3
0 $accept: exp $end .
the reader.
@example
- state 4
+ State 4
1 exp: exp '+' . exp
exp go to state 8
- state 5
+ State 5
2 exp: exp '-' . exp
exp go to state 9
- state 6
+ State 6
3 exp: exp '*' . exp
exp go to state 10
- state 7
+ State 7
4 exp: exp '/' . exp
1 shift/reduce}:
@example
- state 8
+ State 8
1 exp: exp . '+' exp
1 | exp '+' exp .
@option{--report=lookahead}, Bison specifies these lookahead tokens:
@example
- state 8
+ State 8
1 exp: exp . '+' exp
1 | exp '+' exp . [$end, '+', '-', '/']
@example
@group
- state 9
+ State 9
1 exp: exp . '+' exp
2 | exp . '-' exp
@end group
@group
- state 10
+ State 10
1 exp: exp . '+' exp
2 | exp . '-' exp
@end group
@group
- state 11
+ State 11
1 exp: exp . '+' exp
2 | exp . '-' exp
@noindent
Observe that state 11 contains conflicts not only due to the lack of
- precedence of @samp{/} with respect to @samp{+}, @samp{-}, and
- @samp{*}, but also because the
- associativity of @samp{/} is not specified.
+ precedence of @samp{/} with respect to @samp{+}, @samp{-}, and @samp{*}, but
+ also because the associativity of @samp{/} is not specified.
- Note that Bison may also produce an HTML version of this output, via an XML
- file and XSLT processing (@pxref{Xml}).
+ Bison may also produce an HTML version of this output, via an XML file and
+ XSLT processing (@pxref{Xml,,Visualizing your parser in multiple formats}).
@c ================================================= Graphical Representation
(@pxref{Invocation, , Invoking Bison}). Its name is made by removing
@samp{.tab.c} or @samp{.c} from the parser implementation file name, and
adding @samp{.dot} instead. If the grammar file is @file{foo.y}, the
- Graphviz output file is called @file{foo.dot}.
+ Graphviz output file is called @file{foo.dot}. A DOT file may also be
+ produced via an XML file and XSLT processing (@pxref{Xml,,Visualizing your
+ parser in multiple formats}).
+
The following grammar file, @file{rr.y}, will be used in the sequel:
@end group
@end example
- The graphical output is very similar to the textual one, and as such it is
- easier understood by making direct comparisons between them. See
- @ref{Debugging, , Debugging Your Parser} for a detailled analysis of the
- textual report.
+ The graphical output
+ @ifnotinfo
+ (see @ref{fig:graph})
+ @end ifnotinfo
+ is very similar to the textual one, and as such it is easier understood by
+ making direct comparisons between them. @xref{Debugging, , Debugging Your
+ Parser}, for a detailled analysis of the textual report.
+
+ @ifnotinfo
+ @float Figure,fig:graph
+ @image{figs/example, 430pt}
+ @caption{A graphical rendering of the parser.}
+ @end float
+ @end ifnotinfo
@subheading Graphical Representation of States
@example
@group
- state 3
+ State 3
1 exp: a . ";"
This is how reductions are represented in the verbose file @file{rr.output}:
@example
- state 1
+ State 1
3 a: "0" . [";"]
4 b: "0" . ["."]
are distinguished by a red filling color on these nodes, just like how they are
reported between square brackets in the verbose file.
- The reduction corresponding to the rule number 0 is the acceptation state. It
- is shown as a blue diamond, labelled "Acc".
+ The reduction corresponding to the rule number 0 is the acceptation
+ state. It is shown as a blue diamond, labelled ``Acc''.
@subheading Graphical representation of go tos
The @samp{go to} jump transitions are represented as dotted lines bearing
the name of the rule being jumped to.
- Note that a DOT file may also be produced via an XML file and XSLT
- processing (@pxref{Xml}).
-
@c ================================================= XML
@node Xml
@cindex xml
Bison supports two major report formats: textual output
- (@pxref{Understanding}) when invoked with option @option{--verbose}, and DOT
- (@pxref{Graphviz}) when invoked with option @option{--graph}. However,
+ (@pxref{Understanding, ,Understanding Your Parser}) when invoked
+ with option @option{--verbose}, and DOT
+ (@pxref{Graphviz,, Visualizing Your Parser}) when invoked with
+ option @option{--graph}. However,
another alternative is to output an XML file that may then be, with
@command{xsltproc}, rendered as either a raw text format equivalent to the
verbose file, or as an HTML version of the same file, with clickable
XSLT have no difference whatsoever with those obtained by invoking
@command{bison} with options @option{--verbose} or @option{--graph}.
- The textual file is generated when the options @option{-x} or
+ The XML file is generated when the options @option{-x} or
@option{--xml[=FILE]} are specified, see @ref{Invocation,,Invoking Bison}.
If not specified, its name is made by removing @samp{.tab.c} or @samp{.c}
from the parser implementation file name, and adding @samp{.xml} instead.
@item xml2dot.xsl
Used to output a copy of the DOT visualization of the automaton.
@item xml2text.xsl
- Used to output a copy of the .output file.
+ Used to output a copy of the @samp{.output} file.
@item xml2xhtml.xsl
- Used to output an xhtml enhancement of the .output file.
+ Used to output an xhtml enhancement of the @samp{.output} file.
@end table
- Sample usage (requires @code{xsltproc}):
+ Sample usage (requires @command{xsltproc}):
@example
- $ bison -x input.y
+ $ bison -x gr.y
@group
$ bison --print-datadir
/usr/local/share/bison
@end group
- $ xsltproc /usr/local/share/bison/xslt/xml2xhtml.xsl input.xml > input.html
+ $ xsltproc /usr/local/share/bison/xslt/xml2xhtml.xsl gr.xml >gr.html
@end example
@c ================================================= Tracing
@item the directive @samp{%debug}
@findex %debug
Add the @code{%debug} directive (@pxref{Decl Summary, ,Bison Declaration
-Summary}). This is a Bison extension, especially useful for languages that
-don't use a preprocessor. Unless POSIX and Yacc portability matter to you,
-this is the preferred solution.
+Summary}). This Bison extension is maintained for backward
+compatibility with previous versions of Bison.
+
+@item the variable @samp{parse.trace}
+@findex %define parse.trace
+Add the @samp{%define parse.trace} directive (@pxref{%define
+Summary,,parse.trace}), or pass the @option{-Dparse.trace} option
+(@pxref{Bison Options}). This is a Bison extension, which is especially
+useful for languages that don't use a preprocessor. Unless POSIX and Yacc
+portability matter to you, this is the preferred solution.
@end table
-We suggest that you always enable the debug option so that debugging is
+We suggest that you always enable the trace option so that debugging is
always possible.
@findex YYFPRINTF
@noindent
The previous reduction demonstrates the @code{%printer} directive for
- @code{<val>}: both the token @code{NUM} and the resulting non-terminal
+ @code{<val>}: both the token @code{NUM} and the resulting nonterminal
@code{exp} have @samp{1} as value.
@example
conflicts is not reported, so @option{-W} and @option{--warning} then have
no effect on the conflict report.
+@item deprecated
+Deprecated constructs whose support will be removed in future versions of
+Bison.
+
@item other
All warnings not categorized above. These warnings are enabled by default.
@item none
Turn off all the warnings.
@item error
-Treat warnings as errors.
+See @option{-Werror}, below.
@end table
A category can be turned off by prefixing its name with @samp{no-}. For
instance, @option{-Wno-yacc} will hide the warnings about
POSIX Yacc incompatibilities.
+@item -Werror[=@var{category}]
+@itemx -Wno-error[=@var{category}]
+Enable warnings falling in @var{category}, and treat them as errors. If no
+@var{category} is given, it defaults to making all enabled warnings into errors.
+
+@var{category} is the same as for @option{--warnings}, with the exception that
+it may not be prefixed with @samp{no-} (see above).
+
+Prefixed with @samp{no}, it deactivates the error treatment for this
+@var{category}. However, the warning itself won't be disabled, or enabled, by
+this option.
+
+Note that the precedence of the @samp{=} and @samp{,} operators is such that
+the following commands are @emph{not} equivalent, as the first will not treat
+S/R conflicts as errors.
+
+@example
+$ bison -Werror=yacc,conflicts-sr input.y
+$ bison -Werror=yacc,error=conflicts-sr input.y
+@end example
+
@item -f [@var{feature}]
@itemx --feature[=@var{feature}]
Activate miscellaneous @var{feature}. @var{feature} can be one of:
@option{-fdiagnostics-show-caret}, or Clang's @option{-fcaret-diagnotics}. The
location provided with the message is used to quote the corresponding line of
the source file, underlining the important part of it with carets (^). Here is
- an example, using the following file @file{input.y}:
+ an example, using the following file @file{in.y}:
@example
%type <ival> exp
@example
@group
- input.y:3.20-23: error: ambiguous reference: '$exp'
+ in.y:3.20-23: error: ambiguous reference: '$exp'
exp: exp '+' exp @{ $exp = $1 + $2; @};
^^^^
@end group
@group
- input.y:3.1-3: refers to: $exp at $$
+ in.y:3.1-3: refers to: $exp at $$
exp: exp '+' exp @{ $exp = $1 + $2; @};
^^^
@end group
@group
- input.y:3.6-8: refers to: $exp at $1
+ in.y:3.6-8: refers to: $exp at $1
exp: exp '+' exp @{ $exp = $1 + $2; @};
^^^
@end group
@group
- input.y:3.14-16: refers to: $exp at $3
+ in.y:3.14-16: refers to: $exp at $3
exp: exp '+' exp @{ $exp = $1 + $2; @};
^^^
@end group
@group
- input.y:3.32-33: error: $2 of 'exp' has no declared type
+ in.y:3.32-33: error: $2 of 'exp' has no declared type
exp: exp '+' exp @{ $exp = $1 + $2; @};
^^
@end group
When run, @command{bison} will create several entities in the @samp{yy}
namespace.
-@findex %define namespace
-Use the @samp{%define namespace} directive to change the namespace
-name, see @ref{%define Summary,,namespace}. The various classes are
-generated in the following files:
+@findex %define api.namespace
+Use the @samp{%define api.namespace} directive to change the namespace name,
+see @ref{%define Summary,,api.namespace}. The various classes are generated
+in the following files:
@table @file
@item position.hh
@itemx location.hh
The definition of the classes @code{position} and @code{location}, used for
-location tracking. These files are not generated if the @code{%define}
-variable @code{api.location.type} is defined. @xref{C++ Location Values}.
+location tracking when enabled. These files are not generated if the
+@code{%define} variable @code{api.location.type} is defined. @xref{C++
+Location Values}.
@item stack.hh
An auxiliary class @code{stack} used by the parser.
@c - YYSTYPE
@c - Printer and destructor
+Bison supports two different means to handle semantic values in C++. One is
+alike the C interface, and relies on unions (@pxref{C++ Unions}). As C++
+practitioners know, unions are inconvenient in C++, therefore another
+approach is provided, based on variants (@pxref{C++ Variants}).
+
+@menu
+* C++ Unions:: Semantic values cannot be objects
+* C++ Variants:: Using objects as semantic values
+@end menu
+
+@node C++ Unions
+@subsubsection C++ Unions
+
The @code{%union} directive works as for C, see @ref{Union Decl, ,The
Collection of Value Types}. In particular it produces a genuine
-@code{union}@footnote{In the future techniques to allow complex types
-within pseudo-unions (similar to Boost variants) might be implemented to
-alleviate these issues.}, which have a few specific features in C++.
+@code{union}, which have a few specific features in C++.
@itemize @minus
@item
The type @code{YYSTYPE} is defined but its use is discouraged: rather
only means to avoid leaks. @xref{Destructor Decl, , Freeing Discarded
Symbols}.
+@node C++ Variants
+@subsubsection C++ Variants
+
+Starting with version 2.6, Bison provides a @emph{variant} based
+implementation of semantic values for C++. This alleviates all the
+limitations reported in the previous section, and in particular, object
+types can be used without pointers.
+
+To enable variant-based semantic values, set @code{%define} variable
+@code{variant} (@pxref{%define Summary,, variant}). Once this defined,
+@code{%union} is ignored, and instead of using the name of the fields of the
+@code{%union} to ``type'' the symbols, use genuine types.
+
+For instance, instead of
+
+@example
+%union
+@{
+ int ival;
+ std::string* sval;
+@}
+%token <ival> NUMBER;
+%token <sval> STRING;
+@end example
+
+@noindent
+write
+
+@example
+%token <int> NUMBER;
+%token <std::string> STRING;
+@end example
+
+@code{STRING} is no longer a pointer, which should fairly simplify the user
+actions in the grammar and in the scanner (in particular the memory
+management).
+
+Since C++ features destructors, and since it is customary to specialize
+@code{operator<<} to support uniform printing of values, variants also
+typically simplify Bison printers and destructors.
+
+Variants are stricter than unions. When based on unions, you may play any
+dirty game with @code{yylval}, say storing an @code{int}, reading a
+@code{char*}, and then storing a @code{double} in it. This is no longer
+possible with variants: they must be initialized, then assigned to, and
+eventually, destroyed.
+
+@deftypemethod {semantic_type} {T&} build<T> ()
+Initialize, but leave empty. Returns the address where the actual value may
+be stored. Requires that the variant was not initialized yet.
+@end deftypemethod
+
+@deftypemethod {semantic_type} {T&} build<T> (const T& @var{t})
+Initialize, and copy-construct from @var{t}.
+@end deftypemethod
+
+
+@strong{Warning}: We do not use Boost.Variant, for two reasons. First, it
+appeared unacceptable to require Boost on the user's machine (i.e., the
+machine on which the generated parser will be compiled, not the machine on
+which @command{bison} was run). Second, for each possible semantic value,
+Boost.Variant not only stores the value, but also a tag specifying its
+type. But the parser already ``knows'' the type of the semantic value, so
+that would be duplicating the information.
+
+Therefore we developed light-weight variants whose type tag is external (so
+they are really like @code{unions} for C++ actually). But our code is much
+less mature that Boost.Variant. So there is a number of limitations in
+(the current implementation of) variants:
+@itemize
+@item
+Alignment must be enforced: values should be aligned in memory according to
+the most demanding type. Computing the smallest alignment possible requires
+meta-programming techniques that are not currently implemented in Bison, and
+therefore, since, as far as we know, @code{double} is the most demanding
+type on all platforms, alignments are enforced for @code{double} whatever
+types are actually used. This may waste space in some cases.
+
+@item
+Our implementation is not conforming with strict aliasing rules. Alias
+analysis is a technique used in optimizing compilers to detect when two
+pointers are disjoint (they cannot ``meet''). Our implementation breaks
+some of the rules that G++ 4.4 uses in its alias analysis, so @emph{strict
+alias analysis must be disabled}. Use the option
+@option{-fno-strict-aliasing} to compile the generated parser.
+
+@item
+There might be portability issues we are not aware of.
+@end itemize
+
+As far as we know, these limitations @emph{can} be alleviated. All it takes
+is some time and/or some talented C++ hacker willing to contribute to Bison.
@node C++ Location Values
@subsection C++ Location Values
genuine code only the latter is used.
@menu
-* C++ position:: One point in the source file
-* C++ location:: Two points in the source file
+* C++ position:: One point in the source file
+* C++ location:: Two points in the source file
* User Defined Location Type:: Required interface for locations
@end menu
@defcv {Type} {parser} {semantic_type}
@defcvx {Type} {parser} {location_type}
-The types for semantics value and locations.
+The types for semantic values and locations (if enabled).
@end defcv
@defcv {Type} {parser} {token}
(@pxref{Calc++ Scanner}).
@end defcv
+@defcv {Type} {parser} {syntax_error}
+This class derives from @code{std::runtime_error}. Throw instances of it
+from the scanner or from the user actions to raise parse errors. This is
+equivalent with first
+invoking @code{error} to report the location and message of the syntax
+error, and then to invoke @code{YYERROR} to enter the error-recovery mode.
+But contrary to @code{YYERROR} which can only be invoked from user actions
+(i.e., written in the action itself), the exception can be thrown from
+function invoked from the user action.
+@end defcv
+
@deftypemethod {parser} {} parser (@var{type1} @var{arg1}, ...)
Build a new parser object. There are no arguments by default, unless
@samp{%parse-param @{@var{type1} @var{arg1}@}} was used.
@end deftypemethod
+@deftypemethod {syntax_error} {} syntax_error (const location_type& @var{l}, const std::string& @var{m})
+@deftypemethodx {syntax_error} {} syntax_error (const std::string& @var{m})
+Instantiate a syntax-error exception.
+@end deftypemethod
+
@deftypemethod {parser} {int} parse ()
Run the syntactic analysis, and return 0 on success, 1 otherwise.
@end deftypemethod
@deftypemethod {parser} {void} error (const location_type& @var{l}, const std::string& @var{m})
+@deftypemethodx {parser} {void} error (const std::string& @var{m})
The definition for this member function must be supplied by the user:
the parser uses it to report a parser error occurring at @var{l},
-described by @var{m}.
+described by @var{m}. If location tracking is not enabled, the second
+signature is used.
@end deftypemethod
The parser invokes the scanner by calling @code{yylex}. Contrary to C
parsers, C++ parsers are always pure: there is no point in using the
-@code{%define api.pure full} directive. Therefore the interface is as follows.
+@samp{%define api.pure} directive. The actual interface with @code{yylex}
+depends whether you use unions, or variants.
+
+@menu
+* Split Symbols:: Passing symbols as two/three components
+* Complete Symbols:: Making symbols a whole
+@end menu
+
+@node Split Symbols
+@subsubsection Split Symbols
+
+The interface is as follows.
@deftypemethod {parser} {int} yylex (semantic_type* @var{yylval}, location_type* @var{yylloc}, @var{type1} @var{arg1}, ...)
-Return the next token. Its type is the return value, its semantic
-value and location being @var{yylval} and @var{yylloc}. Invocations of
+@deftypemethodx {parser} {int} yylex (semantic_type* @var{yylval}, @var{type1} @var{arg1}, ...)
+Return the next token. Its type is the return value, its semantic value and
+location (if enabled) being @var{yylval} and @var{yylloc}. Invocations of
@samp{%lex-param @{@var{type1} @var{arg1}@}} yield additional arguments.
@end deftypemethod
+Note that when using variants, the interface for @code{yylex} is the same,
+but @code{yylval} is handled differently.
+
+Regular union-based code in Lex scanner typically look like:
+
+@example
+[0-9]+ @{
+ yylval.ival = text_to_int (yytext);
+ return yy::parser::INTEGER;
+ @}
+[a-z]+ @{
+ yylval.sval = new std::string (yytext);
+ return yy::parser::IDENTIFIER;
+ @}
+@end example
+
+Using variants, @code{yylval} is already constructed, but it is not
+initialized. So the code would look like:
+
+@example
+[0-9]+ @{
+ yylval.build<int>() = text_to_int (yytext);
+ return yy::parser::INTEGER;
+ @}
+[a-z]+ @{
+ yylval.build<std::string> = yytext;
+ return yy::parser::IDENTIFIER;
+ @}
+@end example
+
+@noindent
+or
+
+@example
+[0-9]+ @{
+ yylval.build(text_to_int (yytext));
+ return yy::parser::INTEGER;
+ @}
+[a-z]+ @{
+ yylval.build(yytext);
+ return yy::parser::IDENTIFIER;
+ @}
+@end example
+
+
+@node Complete Symbols
+@subsubsection Complete Symbols
+
+If you specified both @code{%define variant} and
+@code{%define api.token.constructor},
+the @code{parser} class also defines the class @code{parser::symbol_type}
+which defines a @emph{complete} symbol, aggregating its type (i.e., the
+traditional value returned by @code{yylex}), its semantic value (i.e., the
+value passed in @code{yylval}, and possibly its location (@code{yylloc}).
+
+@deftypemethod {symbol_type} {} symbol_type (token_type @var{type}, const semantic_type& @var{value}, const location_type& @var{location})
+Build a complete terminal symbol which token type is @var{type}, and which
+semantic value is @var{value}. If location tracking is enabled, also pass
+the @var{location}.
+@end deftypemethod
+
+This interface is low-level and should not be used for two reasons. First,
+it is inconvenient, as you still have to build the semantic value, which is
+a variant, and second, because consistency is not enforced: as with unions,
+it is still possible to give an integer as semantic value for a string.
+
+So for each token type, Bison generates named constructors as follows.
+
+@deftypemethod {symbol_type} {} make_@var{token} (const @var{value_type}& @var{value}, const location_type& @var{location})
+@deftypemethodx {symbol_type} {} make_@var{token} (const location_type& @var{location})
+Build a complete terminal symbol for the token type @var{token} (not
+including the @code{api.token.prefix}) whose possible semantic value is
+@var{value} of adequate @var{value_type}. If location tracking is enabled,
+also pass the @var{location}.
+@end deftypemethod
+
+For instance, given the following declarations:
+
+@example
+%define api.token.prefix "TOK_"
+%token <std::string> IDENTIFIER;
+%token <int> INTEGER;
+%token COLON;
+@end example
+
+@noindent
+Bison generates the following functions:
+
+@example
+symbol_type make_IDENTIFIER(const std::string& v,
+ const location_type& l);
+symbol_type make_INTEGER(const int& v,
+ const location_type& loc);
+symbol_type make_COLON(const location_type& loc);
+@end example
+
+@noindent
+which should be used in a Lex-scanner as follows.
+
+@example
+[0-9]+ return yy::parser::make_INTEGER(text_to_int (yytext), loc);
+[a-z]+ return yy::parser::make_IDENTIFIER(yytext, loc);
+":" return yy::parser::make_COLON(loc);
+@end example
+
+Tokens that do not have an identifier are not accessible: you cannot simply
+use characters such as @code{':'}, they must be declared with @code{%token}.
@node A Complete C++ Example
@subsection A Complete C++ Example
This section demonstrates the use of a C++ parser with a simple but
complete example. This example should be available on your system,
-ready to compile, in the directory @dfn{../bison/examples/calc++}. It
+ready to compile, in the directory @dfn{.../bison/examples/calc++}. It
focuses on the use of Bison, therefore the design of the various C++
classes is very naive: no accessors, no encapsulation of members etc.
We will use a Lex scanner, and more precisely, a Flex scanner, to
-demonstrate the various interaction. A hand written scanner is
+demonstrate the various interactions. A hand-written scanner is
actually easier to interface with.
@menu
@comment file: calc++-driver.hh
@example
// Tell Flex the lexer's prototype ...
-# define YY_DECL \
- yy::calcxx_parser::token_type \
- yylex (yy::calcxx_parser::semantic_type* yylval, \
- yy::calcxx_parser::location_type* yylloc, \
- calcxx_driver& driver)
+# define YY_DECL \
+ yy::calcxx_parser::symbol_type yylex (calcxx_driver& driver)
// ... and declare it for the parser's sake.
YY_DECL;
@end example
@end example
@noindent
-To encapsulate the coordination with the Flex scanner, it is useful to
-have two members function to open and close the scanning phase.
+To encapsulate the coordination with the Flex scanner, it is useful to have
+member functions to open and close the scanning phase.
@comment file: calc++-driver.hh
@example
@comment file: calc++-driver.hh
@example
- // Run the parser. Return 0 on success.
+ // Run the parser on file F.
+ // Return 0 on success.
int parse (const std::string& f);
+ // The name of the file being parsed.
+ // Used later to pass the file name to the location tracker.
std::string file;
+ // Whether parser traces should be generated.
bool trace_parsing;
@end example
%define parser_class_name "calcxx_parser"
@end example
+@noindent
+@findex %define api.token.constructor
+@findex %define variant
+This example will use genuine C++ objects as semantic values, therefore, we
+require the variant-based interface. To make sure we properly use it, we
+enable assertions. To fully benefit from type-safety and more natural
+definition of ``symbol'', we enable @code{api.token.constructor}.
+
+@comment file: calc++-parser.yy
+@example
+%define api.token.constructor
+%define parse.assert
+%define variant
+@end example
+
@noindent
@findex %code requires
-Then come the declarations/inclusions needed to define the
-@code{%union}. Because the parser uses the parsing driver and
-reciprocally, both cannot include the header of the other. Because the
+Then come the declarations/inclusions needed by the semantic values.
+Because the parser uses the parsing driver and reciprocally, both would like
+to include the header of the other, which is, of course, insane. This
+mutual dependency will be broken using forward declarations. Because the
driver's header needs detailed knowledge about the parser class (in
-particular its inner types), it is the parser's header which will simply
-use a forward declaration of the driver.
-@xref{%code Summary}.
+particular its inner types), it is the parser's header which will use a
+forward declaration of the driver. @xref{%code Summary}.
@comment file: calc++-parser.yy
@example
-%code requires @{
+%code requires
+@{
# include <string>
class calcxx_driver;
@}
@comment file: calc++-parser.yy
@example
// The parsing context.
-%parse-param @{ calcxx_driver& driver @}
-%lex-param @{ calcxx_driver& driver @}
+%param @{ calcxx_driver& driver @}
@end example
@noindent
-Then we request the location tracking feature, and initialize the
+Then we request location tracking, and initialize the
first location's file name. Afterward new locations are computed
relatively to the previous locations: the file name will be
-automatically propagated.
+propagated.
@comment file: calc++-parser.yy
@example
@end example
@noindent
-Use the two following directives to enable parser tracing and verbose error
+Use the following two directives to enable parser tracing and verbose error
messages. However, verbose error messages can contain incorrect information
(@pxref{LAC}).
@comment file: calc++-parser.yy
@example
-%debug
-%error-verbose
-@end example
-
-@noindent
-Semantic values cannot use ``real'' objects, but only pointers to
-them.
-
-@comment file: calc++-parser.yy
-@example
-// Symbols.
-%union
-@{
- int ival;
- std::string *sval;
-@};
+%define parse.trace
+%define parse.error verbose
@end example
@noindent
@comment file: calc++-parser.yy
@example
-%code @{
+%code
+@{
# include "calc++-driver.hh"
@}
@end example
@noindent
The token numbered as 0 corresponds to end of file; the following line
-allows for nicer error messages referring to ``end of file'' instead
-of ``$end''. Similarly user friendly named are provided for each
-symbol. Note that the tokens names are prefixed by @code{TOKEN_} to
-avoid name clashes.
+allows for nicer error messages referring to ``end of file'' instead of
+``$end''. Similarly user friendly names are provided for each symbol. To
+avoid name clashes in the generated files (@pxref{Calc++ Scanner}), prefix
+tokens with @code{TOK_} (@pxref{%define Summary,,api.token.prefix}).
@comment file: calc++-parser.yy
@example
-%token END 0 "end of file"
-%token ASSIGN ":="
-%token <sval> IDENTIFIER "identifier"
-%token <ival> NUMBER "number"
-%type <ival> exp
+%define api.token.prefix "TOK_"
+%token
+ END 0 "end of file"
+ ASSIGN ":="
+ MINUS "-"
+ PLUS "+"
+ STAR "*"
+ SLASH "/"
+ LPAREN "("
+ RPAREN ")"
+;
@end example
@noindent
-To enable memory deallocation during error recovery, use
-@code{%destructor}.
+Since we use variant-based semantic values, @code{%union} is not used, and
+both @code{%type} and @code{%token} expect genuine types, as opposed to type
+tags.
-@c FIXME: Document %printer, and mention that it takes a braced-code operand.
@comment file: calc++-parser.yy
@example
-%printer @{ yyoutput << *$$; @} "identifier"
-%destructor @{ delete $$; @} "identifier"
+%token <std::string> IDENTIFIER "identifier"
+%token <int> NUMBER "number"
+%type <int> exp
+@end example
+
+@noindent
+No @code{%destructor} is needed to enable memory deallocation during error
+recovery; the memory, for strings for instance, will be reclaimed by the
+regular destructors. All the values are printed using their
+@code{operator<<} (@pxref{Printer Decl, , Printing Semantic Values}).
-%printer @{ yyoutput << $$; @} <ival>
+@comment file: calc++-parser.yy
+@example
+%printer @{ yyoutput << $$; @} <*>;
@end example
@noindent
-The grammar itself is straightforward.
+The grammar itself is straightforward (@pxref{Location Tracking Calc, ,
+Location Tracking Calculator: @code{ltcalc}}).
@comment file: calc++-parser.yy
@example
| assignments assignment @{@};
assignment:
- "identifier" ":=" exp
- @{ driver.variables[*$1] = $3; delete $1; @};
-
-%left '+' '-';
-%left '*' '/';
-exp: exp '+' exp @{ $$ = $1 + $3; @}
- | exp '-' exp @{ $$ = $1 - $3; @}
- | exp '*' exp @{ $$ = $1 * $3; @}
- | exp '/' exp @{ $$ = $1 / $3; @}
- | "identifier" @{ $$ = driver.variables[*$1]; delete $1; @}
- | "number" @{ $$ = $1; @};
+ "identifier" ":=" exp @{ driver.variables[$1] = $3; @};
+
+%left "+" "-";
+%left "*" "/";
+exp:
+ exp "+" exp @{ $$ = $1 + $3; @}
+| exp "-" exp @{ $$ = $1 - $3; @}
+| exp "*" exp @{ $$ = $1 * $3; @}
+| exp "/" exp @{ $$ = $1 / $3; @}
+| "(" exp ")" @{ std::swap ($$, $2); @}
+| "identifier" @{ $$ = driver.variables[$1]; @}
+| "number" @{ std::swap ($$, $1); @};
%%
@end example
@comment file: calc++-parser.yy
@example
void
-yy::calcxx_parser::error (const yy::calcxx_parser::location_type& l,
+yy::calcxx_parser::error (const location_type& l,
const std::string& m)
@{
driver.error (l, m);
@comment file: calc++-scanner.ll
@example
%@{ /* -*- C++ -*- */
-# include <cstdlib>
# include <cerrno>
# include <climits>
+# include <cstdlib>
# include <string>
# include "calc++-driver.hh"
# include "calc++-parser.hh"
-/* Work around an incompatibility in flex (at least versions
- 2.5.31 through 2.5.33): it generates code that does
- not conform to C89. See Debian bug 333231
- <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333231>. */
+// Work around an incompatibility in flex (at least versions
+// 2.5.31 through 2.5.33): it generates code that does
+// not conform to C89. See Debian bug 333231
+// <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333231>.
# undef yywrap
# define yywrap() 1
-/* By default yylex returns int, we use token_type.
- Unfortunately yyterminate by default returns 0, which is
- not of token_type. */
-#define yyterminate() return token::END
+// The location of the current token.
+static yy::location loc;
%@}
@end example
Because there is no @code{#include}-like feature we don't need
@code{yywrap}, we don't need @code{unput} either, and we parse an
actual file, this is not an interactive session with the user.
-Finally we enable the scanner tracing features.
+Finally, we enable scanner tracing.
@comment file: calc++-scanner.ll
@example
@noindent
The following paragraph suffices to track locations accurately. Each
time @code{yylex} is invoked, the begin position is moved onto the end
-position. Then when a pattern is matched, the end position is
-advanced of its width. In case it matched ends of lines, the end
+position. Then when a pattern is matched, its width is added to the end
+column. When matching ends of lines, the end
cursor is adjusted, and each time blanks are matched, the begin cursor
is moved onto the end cursor to effectively ignore the blanks
preceding tokens. Comments would be treated equally.
@example
@group
%@{
-# define YY_USER_ACTION yylloc->columns (yyleng);
+ // Code run each time a pattern is matched.
+ # define YY_USER_ACTION loc.columns (yyleng);
%@}
@end group
%%
+@group
%@{
- yylloc->step ();
+ // Code run each time yylex is called.
+ loc.step ();
%@}
-@{blank@}+ yylloc->step ();
-[\n]+ yylloc->lines (yyleng); yylloc->step ();
+@end group
+@{blank@}+ loc.step ();
+[\n]+ loc.lines (yyleng); loc.step ();
@end example
@noindent
-The rules are simple, just note the use of the driver to report errors.
-It is convenient to use a typedef to shorten
-@code{yy::calcxx_parser::token::identifier} into
-@code{token::identifier} for instance.
+The rules are simple. The driver is used to report errors.
@comment file: calc++-scanner.ll
@example
-%@{
- typedef yy::calcxx_parser::token token;
-%@}
- /* Convert ints to the actual type of tokens. */
-[-+*/] return yy::calcxx_parser::token_type (yytext[0]);
-
-":=" return token::ASSIGN;
-
-@group
-@{int@} @{
- errno = 0;
- long n = strtol (yytext, NULL, 10);
- if (! (INT_MIN <= n && n <= INT_MAX && errno != ERANGE))
- driver.error (*yylloc, "integer is out of range");
- yylval->ival = n;
- return token::NUMBER;
- @}
-@end group
-
-@group
-@{id@} @{
- yylval->sval = new std::string (yytext);
- return token::IDENTIFIER;
- @}
+"-" return yy::calcxx_parser::make_MINUS(loc);
+"+" return yy::calcxx_parser::make_PLUS(loc);
+"*" return yy::calcxx_parser::make_STAR(loc);
+"/" return yy::calcxx_parser::make_SLASH(loc);
+"(" return yy::calcxx_parser::make_LPAREN(loc);
+")" return yy::calcxx_parser::make_RPAREN(loc);
+":=" return yy::calcxx_parser::make_ASSIGN(loc);
+
+@group
+@{int@} @{
+ errno = 0;
+ long n = strtol (yytext, NULL, 10);
+ if (! (INT_MIN <= n && n <= INT_MAX && errno != ERANGE))
+ driver.error (loc, "integer is out of range");
+ return yy::calcxx_parser::make_NUMBER(n, loc);
+@}
@end group
-
-. driver.error (*yylloc, "invalid character");
+@{id@} return yy::calcxx_parser::make_IDENTIFIER(yytext, loc);
+. driver.error (loc, "invalid character");
+<<EOF>> return yy::calcxx_parser::make_END(loc);
%%
@end example
@noindent
-Finally, because the scanner related driver's member function depend
+Finally, because the scanner-related driver's member-functions depend
on the scanner's data, it is simpler to implement them in this file.
@comment file: calc++-scanner.ll
int
main (int argc, char *argv[])
@{
+ int res = 0;
calcxx_driver driver;
for (int i = 1; i < argc; ++i)
if (argv[i] == std::string ("-p"))
driver.trace_scanning = true;
else if (!driver.parse (argv[i]))
std::cout << driver.result << std::endl;
+ else
+ res = 1;
+ return res;
@}
@end group
@end example
Contrary to C parsers, Java parsers do not use global variables; the
state of the parser is always local to an instance of the parser class.
Therefore, all Java parsers are ``pure'', and the @code{%pure-parser}
-and @code{%define api.pure full} directives does not do anything when used in
-Java.
+and @code{%define api.pure} directives do nothing when used in Java.
Push parsers are currently unsupported in Java and @code{%define
api.push-pull} have no effect.
@code{%defines} directive or the @option{-d}/@option{--defines} options.
@c FIXME: Possible code change.
-Currently, support for debugging and verbose errors are always compiled
-in. Thus the @code{%debug} and @code{%token-table} directives and the
+Currently, support for tracing is always compiled
+in. Thus the @samp{%define parse.trace} and @samp{%token-table}
+directives and the
@option{-t}/@option{--debug} and @option{-k}/@option{--token-table}
options have no effect. This may change in the future to eliminate
-unused code in the generated parser, so use @code{%debug} and
-@code{%verbose-error} explicitly if needed. Also, in the future the
+unused code in the generated parser, so use @samp{%define parse.trace}
+explicitly
+if needed. Also, in the future the
@code{%token-table} directive might enable a public interface to
access the token names and codes.
+Getting a ``code too large'' error from the Java compiler means the code
+hit the 64KB bytecode per method limitation of the Java class file.
+Try reducing the amount of code in actions and static initializers;
+otherwise, report a bug so that the parser skeleton will be improved.
+
+
@node Java Semantic Values
@subsection Java Semantic Values
@c - No %union, specify type in %type/%token.
By default, the semantic stack is declared to have @code{Object} members,
which means that the class types you specify can be of any class.
To improve the type safety of the parser, you can declare the common
-superclass of all the semantic values using the @code{%define stype}
+superclass of all the semantic values using the @samp{%define stype}
directive. For example, after the following declaration:
@example
The name of the generated parser class defaults to @code{YYParser}. The
@code{YY} prefix may be changed using the @code{%name-prefix} directive
or the @option{-p}/@option{--name-prefix} option. Alternatively, use
-@code{%define parser_class_name "@var{name}"} to give a custom name to
+@samp{%define parser_class_name "@var{name}"} to give a custom name to
the class. The interface of this class is detailed below.
By default, the parser class has package visibility. A declaration
-@code{%define public} will change to public visibility. Remember that,
+@samp{%define public} will change to public visibility. Remember that,
according to the Java language specification, the name of the @file{.java}
file should match the name of the class in this case. Similarly, you can
use @code{abstract}, @code{final} and @code{strictfp} with the
@code{%define} declaration to add other modifiers to the parser class.
+A single @samp{%define annotations "@var{annotations}"} directive can
+be used to add any number of annotations to the parser class.
The Java package name of the parser class can be specified using the
-@code{%define package} directive. The superclass and the implemented
+@samp{%define package} directive. The superclass and the implemented
interfaces of the parser class can be specified with the @code{%define
-extends} and @code{%define implements} directives.
+extends} and @samp{%define implements} directives.
The parser class defines an inner class, @code{Location}, that is used
for location tracking (see @ref{Java Location Values}), and a inner
below, all the other members and fields are preceded with a @code{yy} or
@code{YY} prefix to avoid clashes with user code.
-@c FIXME: The following constants and variables are still undocumented:
-@c @code{bisonVersion}, @code{bisonSkeleton} and @code{errorVerbose}.
-
The parser class can be extended using the @code{%parse-param}
directive. Each occurrence of the directive will add a @code{protected
final} field to the parser class, and an argument to its constructor,
which initialize them automatically.
-Token names defined by @code{%token} and the predefined @code{EOF} token
-name are added as constant fields to the parser class.
-
@deftypeop {Constructor} {YYParser} {} YYParser (@var{lex_param}, @dots{}, @var{parse_param}, @dots{})
Build a new parser object with embedded @code{%code lexer}. There are
-no parameters, unless @code{%parse-param}s and/or @code{%lex-param}s are
-used.
+no parameters, unless @code{%param}s and/or @code{%parse-param}s and/or
+@code{%lex-param}s are used.
+
+Use @code{%code init} for code added to the start of the constructor
+body. This is especially useful to initialize superclasses. Use
+@samp{%define init_throws} to specify any uncaught exceptions.
@end deftypeop
@deftypeop {Constructor} {YYParser} {} YYParser (Lexer @var{lexer}, @var{parse_param}, @dots{})
Build a new parser object using the specified scanner. There are no
-additional parameters unless @code{%parse-param}s are used.
+additional parameters unless @code{%param}s and/or @code{%parse-param}s are
+used.
If the scanner is defined by @code{%code lexer}, this constructor is
declared @code{protected} and is called automatically with a scanner
-created with the correct @code{%lex-param}s.
+created with the correct @code{%param}s and/or @code{%lex-param}s.
+
+Use @code{%code init} for code added to the start of the constructor
+body. This is especially useful to initialize superclasses. Use
+@samp{%define init_throws} to specify any uncaught exceptions.
@end deftypeop
@deftypemethod {YYParser} {boolean} parse ()
@code{false} otherwise.
@end deftypemethod
+@deftypemethod {YYParser} {boolean} getErrorVerbose ()
+@deftypemethodx {YYParser} {void} setErrorVerbose (boolean @var{verbose})
+Get or set the option to produce verbose error messages. These are only
+available with @samp{%define parse.error verbose}, which also turns on
+verbose error messages.
+@end deftypemethod
+
+@deftypemethod {YYParser} {void} yyerror (String @var{msg})
+@deftypemethodx {YYParser} {void} yyerror (Position @var{pos}, String @var{msg})
+@deftypemethodx {YYParser} {void} yyerror (Location @var{loc}, String @var{msg})
+Print an error message using the @code{yyerror} method of the scanner
+instance in use. The @code{Location} and @code{Position} parameters are
+available only if location tracking is active.
+@end deftypemethod
+
@deftypemethod {YYParser} {boolean} recovering ()
During the syntactic analysis, return @code{true} if recovering
from a syntax error.
or nonzero, full tracing.
@end deftypemethod
+@deftypecv {Constant} {YYParser} {String} {bisonVersion}
+@deftypecvx {Constant} {YYParser} {String} {bisonSkeleton}
+Identify the Bison version and skeleton used to generate this parser.
+@end deftypecv
+
@node Java Scanner Interface
@subsection Java Scanner Interface
There are two possible ways to interface a Bison-generated Java parser
with a scanner: the scanner may be defined by @code{%code lexer}, or
defined elsewhere. In either case, the scanner has to implement the
-@code{Lexer} inner interface of the parser class.
+@code{Lexer} inner interface of the parser class. This interface also
+contain constants for all user-defined token names and the predefined
+@code{EOF} token.
In the first case, the body of the scanner class is placed in
@code{%code lexer} blocks. If you want to pass parameters from the
value and location are saved and returned by the their methods in the
interface.
-Use @code{%define lex_throws} to specify any uncaught exceptions.
+Use @samp{%define lex_throws} to specify any uncaught exceptions.
Default is @code{java.io.IOException}.
@end deftypemethod
@deftypemethod {Lexer} {Object} getLVal ()
Return the semantic value of the last token that yylex returned.
-The return type can be changed using @code{%define stype
+The return type can be changed using @samp{%define stype
"@var{class-name}".}
@end deftypemethod
The following special constructs can be uses in Java actions.
Other analogous C action features are currently unavailable for Java.
-Use @code{%define throws} to specify any uncaught exceptions from parser
+Use @samp{%define throws} to specify any uncaught exceptions from parser
actions, and initial actions specified by @code{%initial-action}.
@defvar $@var{n}
@defvar $$
The semantic value for the grouping made by the current rule. As a
value, this is in the base type (@code{Object} or as specified by
-@code{%define stype}) as in not cast to the declared subtype because
+@samp{%define stype}) as in not cast to the declared subtype because
casts are not allowed on the left-hand side of Java assignments.
Use an explicit Java cast if the correct subtype is needed.
@xref{Java Semantic Values}.
@xref{Error Recovery}.
@end deftypefn
-@deftypefn {Function} {protected void} yyerror (String msg)
-@deftypefnx {Function} {protected void} yyerror (Position pos, String msg)
-@deftypefnx {Function} {protected void} yyerror (Location loc, String msg)
+@deftypefn {Function} {void} yyerror (String @var{msg})
+@deftypefnx {Function} {void} yyerror (Position @var{loc}, String @var{msg})
+@deftypefnx {Function} {void} yyerror (Location @var{loc}, String @var{msg})
Print an error message using the @code{yyerror} method of the scanner
-instance in use.
+instance in use. The @code{Location} and @code{Position} parameters are
+available only if location tracking is active.
@end deftypefn
@item @code{%code imports}
blocks are placed at the beginning of the Java source code. They may
include copyright notices. For a @code{package} declarations, it is
-suggested to use @code{%define package} instead.
+suggested to use @samp{%define package} instead.
@item unqualified @code{%code}
blocks are placed inside the parser class.
@deffn {Directive} %name-prefix "@var{prefix}"
The prefix of the parser class name @code{@var{prefix}Parser} if
-@code{%define parser_class_name} is not used. Default is @code{YY}.
+@samp{%define parser_class_name} is not used. Default is @code{YY}.
@xref{Java Bison Interface}.
@end deffn
@xref{Java Differences}.
@end deffn
+@deffn {Directive} {%code init} @{ @var{code} @dots{} @}
+Code inserted at the beginning of the parser constructor body.
+@xref{Java Parser Interface}.
+@end deffn
+
@deffn {Directive} {%code lexer} @{ @var{code} @dots{} @}
Code added to the body of a inner lexer class within the parser class.
@xref{Java Scanner Interface}.
@end deffn
@deffn {Directive} %@{ @var{code} @dots{} %@}
-Not supported. Use @code{%code import} instead.
+Not supported. Use @code{%code imports} instead.
@xref{Java Differences}.
@end deffn
@xref{Java Bison Interface}.
@end deffn
+@deffn {Directive} {%define annotations} "@var{annotations}"
+The Java annotations for the parser class. Default is none.
+@xref{Java Bison Interface}.
+@end deffn
+
@deffn {Directive} {%define extends} "@var{superclass}"
The superclass of the parser class. Default is none.
@xref{Java Bison Interface}.
@xref{Java Bison Interface}.
@end deffn
+@deffn {Directive} {%define init_throws} "@var{exceptions}"
+The exceptions thrown by @code{%code init} from the parser class
+constructor. Default is none.
+@xref{Java Parser Interface}.
+@end deffn
+
@deffn {Directive} {%define lex_throws} "@var{exceptions}"
The exceptions thrown by the @code{yylex} method of the lexer, a
comma-separated list. Default is @code{java.io.IOException}.
@end deffn
@deffn {Variable} @@@var{n}
+ @deffnx {Symbol} @@@var{n}
In an action, the location of the @var{n}-th symbol of the right-hand side
of the rule. @xref{Tracking Locations}.
+
+ In a grammar, the Bison-generated nonterminal symbol for a mid-rule action
+ with a semantical value. @xref{Mid-Rule Action Translation}.
@end deffn
@deffn {Variable} @@@var{name}
- In an action, the location of a symbol addressed by name. @xref{Tracking
- Locations}.
+ @deffnx {Variable} @@[@var{name}]
+ In an action, the location of a symbol addressed by @var{name}.
+ @xref{Tracking Locations}.
@end deffn
- @deffn {Variable} @@[@var{name}]
- In an action, the location of a symbol addressed by name. @xref{Tracking
- Locations}.
+ @deffn {Symbol} $@@@var{n}
+ In a grammar, the Bison-generated nonterminal symbol for a mid-rule action
+ with no semantical value. @xref{Mid-Rule Action Translation}.
@end deffn
@deffn {Variable} $$
@end deffn
@deffn {Variable} $@var{name}
- In an action, the semantic value of a symbol addressed by name.
- @xref{Actions}.
- @end deffn
-
- @deffn {Variable} $[@var{name}]
- In an action, the semantic value of a symbol addressed by name.
+ @deffnx {Variable} $[@var{name}]
+ In an action, the semantic value of a symbol addressed by @var{name}.
@xref{Actions}.
@end deffn
Grammar}.
@end deffn
- @deffn {Construct} /*@dots{}*/
- Comment delimiters, as in C.
+@deffn {Directive} %?@{@var{expression}@}
+Predicate actions. This is a type of action clause that may appear in
+rules. The expression is evaluated, and if false, causes a syntax error. In
+GLR parsers during nondeterministic operation,
+this silently causes an alternative parse to die. During deterministic
+operation, it is the same as the effect of YYERROR.
+@xref{Semantic Predicates}.
+
+This feature is experimental.
+More user feedback will help to determine whether it should become a permanent
+feature.
+@end deffn
+
+ @deffn {Construct} /* @dots{} */
+ @deffnx {Construct} // @dots{}
+ Comments, as in C/C++.
@end deffn
@deffn {Delimiter} :
@end deffn
@deffn {Directive} %error-verbose
-Bison declaration to request verbose, specific error message strings
-when @code{yyerror} is called. @xref{Error Reporting}.
+An obsolete directive standing for @samp{%define parse.error verbose}
+(@pxref{Error Reporting, ,The Error Reporting Function @code{yyerror}}).
@end deffn
@deffn {Directive} %file-prefix "@var{prefix}"
@end deffn
@deffn {Directive} %left
-Bison declaration to assign left associativity to token(s).
+Bison declaration to assign precedence and left associativity to token(s).
@xref{Precedence Decl, ,Operator Precedence}.
@end deffn
-@deffn {Directive} %lex-param @{@var{argument-declaration}@}
-Bison declaration to specifying an additional parameter that
+@deffn {Directive} %lex-param @{@var{argument-declaration}@} @dots{}
+Bison declaration to specifying additional arguments that
@code{yylex} should accept. @xref{Pure Calling,, Calling Conventions
for Pure Parsers}.
@end deffn
@end deffn
@deffn {Directive} %nonassoc
-Bison declaration to assign nonassociativity to token(s).
+Bison declaration to assign precedence and nonassociativity to token(s).
@xref{Precedence Decl, ,Operator Precedence}.
@end deffn
@xref{Decl Summary}.
@end deffn
-@deffn {Directive} %parse-param @{@var{argument-declaration}@}
-Bison declaration to specifying an additional parameter that
-@code{yyparse} should accept. @xref{Parser Function,, The Parser
-Function @code{yyparse}}.
+@deffn {Directive} %param @{@var{argument-declaration}@} @dots{}
+Bison declaration to specify additional arguments that both
+@code{yylex} and @code{yyparse} should accept. @xref{Parser Function,, The
+Parser Function @code{yyparse}}.
+@end deffn
+
+@deffn {Directive} %parse-param @{@var{argument-declaration}@} @dots{}
+Bison declaration to specify additional arguments that @code{yyparse}
+should accept. @xref{Parser Function,, The Parser Function @code{yyparse}}.
@end deffn
@deffn {Directive} %prec
@xref{Contextual Precedence, ,Context-Dependent Precedence}.
@end deffn
+@deffn {Directive} %precedence
+Bison declaration to assign precedence to token(s), but no associativity
+@xref{Precedence Decl, ,Operator Precedence}.
+@end deffn
+
@deffn {Directive} %pure-parser
-Deprecated version of @code{%define api.pure} (@pxref{%define
+Deprecated version of @samp{%define api.pure} (@pxref{%define
Summary,,api.pure}), for which Bison is more careful to warn about
unreasonable usage.
@end deffn
@end deffn
@deffn {Directive} %right
-Bison declaration to assign right associativity to token(s).
+Bison declaration to assign precedence and right associativity to token(s).
@xref{Precedence Decl, ,Operator Precedence}.
@end deffn
@deffn {Function} yyerror
User-supplied function to be called by @code{yyparse} on error.
-@xref{Error Reporting, ,The Error
-Reporting Function @code{yyerror}}.
+@xref{Error Reporting, ,The Error Reporting Function @code{yyerror}}.
@end deffn
@deffn {Macro} YYERROR_VERBOSE
-An obsolete macro that you define with @code{#define} in the prologue
-to request verbose, specific error message strings
-when @code{yyerror} is called. It doesn't matter what definition you
-use for @code{YYERROR_VERBOSE}, just whether you define it.
-Supported by the C skeletons only; using
-@code{%error-verbose} is preferred. @xref{Error Reporting}.
+An obsolete macro used in the @file{yacc.c} skeleton, that you define
+with @code{#define} in the prologue to request verbose, specific error
+message strings when @code{yyerror} is called. It doesn't matter what
+definition you use for @code{YYERROR_VERBOSE}, just whether you define
+it. Using @samp{%define parse.error verbose} is preferred
+(@pxref{Error Reporting, ,The Error Reporting Function @code{yyerror}}).
@end deffn
@deffn {Macro} YYFPRINTF
More user feedback will help to stabilize it.)
@end deffn
-@deffn {Macro} YYPARSE_PARAM
-An obsolete macro for specifying the name of a parameter that
-@code{yyparse} should accept. The use of this macro is deprecated, and
-is supported only for Yacc like parsers. @xref{Pure Calling,, Calling
-Conventions for Pure Parsers}.
-@end deffn
-
@deffn {Macro} YYRECOVERING
The expression @code{YYRECOVERING ()} yields 1 when the parser
is recovering from a syntax error, and 0 otherwise.
@item Accepting state
A state whose only action is the accept action.
The accepting state is thus a consistent state.
- @xref{Understanding,,}.
+ @xref{Understanding, ,Understanding Your Parser}.
@item Backus-Naur Form (BNF; also called ``Backus Normal Form'')
Formal method of specifying context-free grammars originally proposed
AC_COMPILE_IFELSE(
[AC_LANG_PROGRAM(
[[#include <limits.h>
- int test_array[CHAR_BIT];]])],
+ int test_array[CHAR_BIT];]])],
[],
[AC_MSG_FAILURE([cannot compile a simple C program])])
+ AC_SUBST([BISON_C_WORKS], [:])
])
# BISON_CHECK_WITH_POSIXLY_CORRECT(CODE)
esac
])
+ # BISON_LANG_COMPILER_POSIXLY_CORRECT
+ # -----------------------------------
+ # Whether the compiler for the current language supports -g in
+ # POSIXLY_CORRECT mode. clang-2.9 on OS X does not, because
+ # "clang-mp-2.9 -o test -g test.c" launches "/usr/bin/dsymutil test -o
+ # test.dSYM" which fails with "error: unable to open executable '-o'".
+ #
+ # Sets <LANG>_COMPILER_POSIXLY_CORRECT to true/false.
+ AC_DEFUN([BISON_LANG_COMPILER_POSIXLY_CORRECT],
+ [AC_CACHE_CHECK([whether $_AC_CC supports POSIXLY_CORRECT=1],
+ [bison_cv_[]_AC_LANG_ABBREV[]_supports_posixly_correct],
+ [BISON_CHECK_WITH_POSIXLY_CORRECT(
+ [AC_LINK_IFELSE([AC_LANG_PROGRAM],
+ [bison_cv_[]_AC_LANG_ABBREV[]_supports_posixly_correct=yes],
+ [bison_cv_[]_AC_LANG_ABBREV[]_supports_posixly_correct=no])])])
+ case $bison_cv_[]_AC_LANG_ABBREV[]_supports_posixly_correct in
+ yes) AC_SUBST(_AC_LANG_PREFIX[_COMPILER_POSIXLY_CORRECT], [true]) ;;
+ no) AC_SUBST(_AC_LANG_PREFIX[_COMPILER_POSIXLY_CORRECT], [false]);;
+ esac
+ ])
+
# BISON_C_COMPILER_POSIXLY_CORRECT
# --------------------------------
- # Whether the compiler supports -g in POSIXLY_CORRECT mode. clang-2.9
- # on OS X does not, because "clang-mp-2.9 -o test -g test.c" launches
- # "/usr/bin/dsymutil test -o test.dSYM" which fails with "error:
- # unable to open executable '-o'".
- #
- # Sets C_COMPILER_POSIXLY_CORRECT to true/false.
+ # Whether the C compiler supports -g in POSIXLY_CORRECT mode.
AC_DEFUN([BISON_C_COMPILER_POSIXLY_CORRECT],
- [AC_CACHE_CHECK([whether $CC supports POSIXLY_CORRECT=1],
- [bison_cv_cc_supports_posixly_correct],
- [BISON_CHECK_WITH_POSIXLY_CORRECT(
[AC_LANG_PUSH([C])
- AC_LINK_IFELSE([AC_LANG_PROGRAM],
- [bison_cv_cc_supports_posixly_correct=yes],
- [bison_cv_cc_supports_posixly_correct=no])
- AC_LANG_POP([C])])])
- case $bison_cv_cc_supports_posixly_correct in
- yes) AC_SUBST([C_COMPILER_POSIXLY_CORRECT], [true]) ;;
- no) AC_SUBST([C_COMPILER_POSIXLY_CORRECT], [false]);;
- esac
+ BISON_LANG_COMPILER_POSIXLY_CORRECT
+ AC_LANG_POP([C])
])
bison_cv_cxx_works=no
AC_COMPILE_IFELSE(
[AC_LANG_PROGRAM(
- [#include <cstdlib>
- #include <iostream>
- #include <map>
- #include <string>
- using namespace std;],
+ [#include <cstdlib>
+ #include <iostream>
+ #include <map>
+ #include <string>
+ using namespace std;],
[std::cerr << "";
cout << "";
- typedef std::pair<unsigned int, int> uipair;
- std::map<unsigned int, int> m;
- std::map<unsigned int, int>::iterator i;
- m.insert (uipair (4, -4));
- for (i = m.begin (); i != m.end (); ++i)
- if (i->first != 4)
- return 1;])],
+ typedef std::pair<unsigned int, int> uipair;
+ std::map<unsigned int, int> m;
+ std::map<unsigned int, int>::iterator i;
+ m.insert (uipair (4, -4));
+ for (i = m.begin (); i != m.end (); ++i)
+ if (i->first != 4)
+ return 1;])],
[AS_IF([AC_TRY_COMMAND([$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_objext $LIBS >&AS_MESSAGE_LOG_FD])],
- [AS_IF([test "$cross_compiling" = yes],
- [bison_cv_cxx_works=cross],
- [AS_IF([AC_TRY_COMMAND(./conftest$ac_exeext)],
- [bison_cv_cxx_works=yes])])])
+ [AS_IF([test "$cross_compiling" = yes],
+ [bison_cv_cxx_works=cross],
+ [AS_IF([AC_TRY_COMMAND(./conftest$ac_exeext)],
+ [bison_cv_cxx_works=yes])])])
rm -f conftest$ac_exeext])
AC_LANG_POP([C++])])
AC_SUBST([BISON_CXX_WORKS])
AM_CONDITIONAL(BISON_CXX_WORKS, test $bison_cv_cxx_works = yes)
])
+
+ # BISON_CXX_COMPILER_POSIXLY_CORRECT
+ # ----------------------------------
+ # Whether the C++ compiler supports -g in POSIXLY_CORRECT mode.
+ AC_DEFUN([BISON_CXX_COMPILER_POSIXLY_CORRECT],
+ [AC_LANG_PUSH([C++])
+ BISON_LANG_COMPILER_POSIXLY_CORRECT
+ AC_LANG_POP([C++])
+ ])
# error "FLEX_PREFIX not defined"
#endif
- /* Whether this version of Flex is (strictly) greater than
- Major.Minor.Subminor. */
- #ifdef YY_FLEX_SUBMINOR_VERSION
- # define FLEX_VERSION \
- (YY_FLEX_MAJOR_VERSION) * 1000000 \
- + (YY_FLEX_MINOR_VERSION) * 1000 \
- + (YY_FLEX_SUBMINOR_VERSION)
- #else
- # define FLEX_VERSION \
- (YY_FLEX_MAJOR_VERSION) * 1000000 \
- + (YY_FLEX_MINOR_VERSION) * 1000
- #endif
+ /* Flex full version as a number. */
+ #define FLEX_VERSION \
+ ((YY_FLEX_MAJOR_VERSION) * 1000000 \
+ + (YY_FLEX_MINOR_VERSION) * 1000 \
+ + (YY_FLEX_SUBMINOR_VERSION))
+
/* Pacify "gcc -Wmissing-prototypes" when flex 2.5.31 is used. */
# if FLEX_VERSION <= 2005031
int FLEX_PREFIX (get_lineno) (void);
static struct obstack obstack_for_string;
-# define STRING_GROW \
+# define STRING_GROW \
obstack_grow (&obstack_for_string, yytext, yyleng)
-# define STRING_FINISH \
- do { \
- obstack_1grow (&obstack_for_string, '\0'); \
- last_string = obstack_finish (&obstack_for_string); \
- } while (0)
+# define STRING_FINISH \
+ (last_string = obstack_finish0 (&obstack_for_string))
-# define STRING_FREE \
+# define STRING_FREE \
obstack_free (&obstack_for_string, last_string)
#endif
if (buf)
{
if (INT_MAX / 2 <= bufsize)
- return INT_MAX;
+ return INT_MAX;
width = mbsnwidth (buf, bufsize, 0);
}
else
switch (*p)
{
case '\n':
- line += line < INT_MAX;
- column = 1;
- p0 = p + 1;
- break;
+ line += line < INT_MAX;
+ column = 1;
+ p0 = p + 1;
+ break;
case '\t':
- column = add_column_width (column, p0, p - p0);
- column = add_column_width (column, NULL, 8 - ((column - 1) & 7));
- p0 = p + 1;
- break;
+ column = add_column_width (column, p0, p - p0);
+ column = add_column_width (column, NULL, 8 - ((column - 1) & 7));
+ p0 = p + 1;
+ break;
default:
- break;
+ break;
}
cur->line = line;
loc->end = *cur;
if (line == INT_MAX && loc->start.line != INT_MAX)
- warn_at (*loc, _("line number overflow"));
+ complain (loc, Wother, _("line number overflow"));
if (column == INT_MAX && loc->start.column != INT_MAX)
- warn_at (*loc, _("column number overflow"));
+ complain (loc, Wother, _("column number overflow"));
}
same file all over for each error. */
struct caret_info
{
- FILE* source;
+ FILE *source;
size_t line;
size_t offset;
};
static struct caret_info caret_info = { NULL, 1, 0 };
- /* Free any allocated ressources and close any open file handles that are
- left-over by the usage of location_caret. */
void
cleanup_caret ()
{
fclose (caret_info.source);
}
- /* Output to OUT the line and caret corresponding to location LOC. */
void
location_caret (FILE *out, location loc)
{
- /* FIXME: find a way to support X-file locations, and only open once each
+ /* FIXME: find a way to support multifile locations, and only open once each
file. That would make the procedure future-proof. */
if (! (caret_info.source
|| (caret_info.source = fopen (loc.start.file, "r")))
}
/* Advance to the line's position, keeping track of the offset. */
- {
- int i;
- for (i = caret_info.line; i < loc.start.line; caret_info.offset++)
- if (fgetc (caret_info.source) == '\n')
- ++i;
- }
- caret_info.line = loc.start.line;
+ while (caret_info.line < loc.start.line)
+ caret_info.line += fgetc (caret_info.source) == '\n';
+ caret_info.offset = ftell (caret_info.source);
/* Read the actual line. Don't update the offset, so that we keep a pointer
to the start of the line. */
{
- ssize_t len = 0;
char *buf = NULL;
- if ((len = getline (&buf, (size_t*) &len, caret_info.source)) != -1)
+ size_t size = 0;
+ ssize_t len = getline (&buf, &size, caret_info.source);
+ if (0 < len)
{
/* The caret of a multiline location ends with the first line. */
int end = loc.start.line != loc.end.line ? len : loc.end.column;
- if (len)
- {
- int i = loc.start.column;
- /* Quote the file, indent by a single column. */
- fputc (' ', out);
- fwrite (buf, 1, len, out);
-
- /* Print the caret, with the same indent as above. */
- fputc (' ', out);
- fprintf (out, "%*s", loc.start.column - 1, "");
- do {
- fputc ('^', out);
- } while (++i < end);
- }
+ /* Quote the file, indent by a single column. */
+ fputc (' ', out);
+ fwrite (buf, 1, len, out);
+
+ /* Print the caret, with the same indent as above. */
+ fprintf (out, " %*s", loc.start.column - 1, "");
+ {
+ int i = loc.start.column;
+ do
+ fputc ('^', out);
+ while (++i < end);
+ }
fputc ('\n', out);
- free (buf);
}
+ free (buf);
}
}
{
/* Must search in reverse since the file name field may
* contain `.' or `:'. */
- char *delim = mbsrchr (loc_str, '.');
+ char *delim = strrchr (loc_str, '.');
aver (delim);
*delim = '\0';
bound->column = atoi (delim+1);
- delim = mbsrchr (loc_str, ':');
+ delim = strrchr (loc_str, ':');
aver (delim);
*delim = '\0';
bound->line = atoi (delim+1);
grammar_start_symbol_set (symbol *sym, location loc)
{
if (start_flag)
- complain_at (loc, _("multiple %s declarations"), "%start");
+ complain (&loc, complaint, _("multiple %s declarations"), "%start");
else
{
start_flag = true;
syms->next = xmalloc (sizeof syms->next[0]);
syms->next->name = uniqstr_new (name);
/* After all symbol type declarations have been parsed, packgram invokes
- record_merge_function_type to set the type. */
+ record_merge_function_type to set the type. */
syms->next->type = NULL;
syms->next->next = NULL;
merge_functions = head.next;
if (merge_function->type != NULL && !UNIQSTR_EQ (merge_function->type, type))
{
unsigned indent = 0;
- complain_at_indent (declaration_loc, &indent,
- _("result type clash on merge function %s: "
- "<%s> != <%s>"),
- quote (merge_function->name), type,
- merge_function->type);
+ complain_indent (&declaration_loc, complaint, &indent,
+ _("result type clash on merge function %s: "
+ "<%s> != <%s>"),
+ quote (merge_function->name), type,
+ merge_function->type);
indent += SUB_INDENT;
- complain_at_indent (merge_function->type_declaration_location, &indent,
- _("previous declaration"));
- }
+ complain_indent (&merge_function->type_declaration_location, complaint,
+ &indent,
+ _("previous declaration"));
+ }
merge_function->type = uniqstr_new (type);
merge_function->type_declaration_location = declaration_loc;
}
/*--------------------------------------.
-| Free all merge-function definitions. |
+| Free all merge-function definitions. |
`--------------------------------------*/
void
if (name->id == sym->tag)
{
- warn_at (name->loc,
- _("duplicated symbol name for %s ignored"),
- quote (sym->tag));
+ complain (&name->loc, Wother,
+ _("duplicated symbol name for %s ignored"),
+ quote (sym->tag));
named_ref_free (name);
}
else
void
grammar_current_rule_begin (symbol *lhs, location loc,
- named_ref *lhs_name)
+ named_ref *lhs_name)
{
symbol_list* p;
++nvars;
}
else if (lhs->class == token_sym)
- complain_at (loc, _("rule given for %s, which is a token"), lhs->tag);
+ complain (&loc, complaint, _("rule given for %s, which is a token"),
+ lhs->tag);
}
static bool
symbol_should_be_used (symbol_list const *s, bool *midrule_warning)
{
- if (symbol_destructor_get (s->content.sym)->code)
+ if (symbol_code_props_get (s->content.sym, destructor)->code)
return true;
if ((s->midrule && s->midrule->action_props.is_value_used)
|| (s->midrule_parent_rule
symbol *first_rhs = r->next->content.sym;
/* If $$ is being set in default way, report if any type mismatch. */
if (first_rhs)
- {
- char const *lhs_type = r->content.sym->type_name;
- const char *rhs_type =
- first_rhs->type_name ? first_rhs->type_name : "";
- if (!UNIQSTR_EQ (lhs_type, rhs_type))
- warn_at (r->location,
- _("type clash on default action: <%s> != <%s>"),
- lhs_type, rhs_type);
- }
+ {
+ char const *lhs_type = r->content.sym->type_name;
+ const char *rhs_type =
+ first_rhs->type_name ? first_rhs->type_name : "";
+ if (!UNIQSTR_EQ (lhs_type, rhs_type))
+ complain (&r->location, Wother,
+ _("type clash on default action: <%s> != <%s>"),
+ lhs_type, rhs_type);
+ }
/* Warn if there is no default for $$ but we need one. */
else
- warn_at (r->location,
- _("empty rule for typed nonterminal, and no action"));
+ complain (&r->location, Wother,
+ _("empty rule for typed nonterminal, and no action"));
}
/* Check that symbol values that should be used are in fact used. */
/* The default action, $$ = $1, `uses' both. */
&& (r->action_props.code || (n != 0 && n != 1)))
{
- void (*warn_at_ptr)(location, char const*, ...) =
- midrule_warning ? midrule_value_at : warn_at;
+ warnings warn_flag = midrule_warning ? Wmidrule_values : Wother;
if (n)
- complain (&r->location, warn_flag, _("unused value: $%d"), n);
- warn_at_ptr (l->location, _("unused value: $%d"), n);
++ complain (&l->location, warn_flag, _("unused value: $%d"), n);
else
- complain (&r->location, warn_flag, _("unset value: $$"));
- warn_at_ptr (l->location, _("unset value: $$"));
++ complain (&l->location, warn_flag, _("unset value: $$"));
}
}
}
it for char literals and strings, which are always tokens. */
if (r->ruleprec
&& r->ruleprec->tag[0] != '\'' && r->ruleprec->tag[0] != '"'
- && !r->ruleprec->declared && !r->ruleprec->prec)
- warn_at (r->location, _("token for %%prec is not defined: %s"),
- r->ruleprec->tag);
+ && r->ruleprec->status != declared && !r->ruleprec->prec)
+ complain (&r->location, Wother,
+ _("token for %%prec is not defined: %s"), r->ruleprec->tag);
}
code_props_rule_action_init (&midrule->action_props,
current_rule->action_props.code,
current_rule->action_props.location,
- midrule, 0);
+ midrule, 0,
+ current_rule->action_props.is_predicate);
code_props_none_init (¤t_rule->action_props);
if (previous_rule_end)
token. */
symbol_class_set (precsym, token_sym, loc, false);
if (current_rule->ruleprec)
- complain_at (loc, _("only one %s allowed per rule"), "%prec");
+ complain (&loc, complaint, _("only one %s allowed per rule"), "%prec");
current_rule->ruleprec = precsym;
}
grammar_current_rule_dprec_set (int dprec, location loc)
{
if (! glr_parser)
- warn_at (loc, _("%s affects only GLR parsers"), "%dprec");
+ complain (&loc, Wother, _("%s affects only GLR parsers"),
+ "%dprec");
if (dprec <= 0)
- complain_at (loc, _("%s must be followed by positive number"), "%dprec");
+ complain (&loc, complaint, _("%s must be followed by positive number"),
+ "%dprec");
else if (current_rule->dprec != 0)
- complain_at (loc, _("only one %s allowed per rule"), "%dprec");
+ complain (&loc, complaint, _("only one %s allowed per rule"), "%dprec");
current_rule->dprec = dprec;
}
grammar_current_rule_merge_set (uniqstr name, location loc)
{
if (! glr_parser)
- warn_at (loc, _("%s affects only GLR parsers"), "%merge");
+ complain (&loc, Wother, _("%s affects only GLR parsers"),
+ "%merge");
if (current_rule->merger != 0)
- complain_at (loc, _("only one %s allowed per rule"), "%merge");
+ complain (&loc, complaint, _("only one %s allowed per rule"), "%merge");
current_rule->merger = get_merge_function (name);
current_rule->merger_declaration_location = loc;
}
void
grammar_current_rule_symbol_append (symbol *sym, location loc,
- named_ref *name)
+ named_ref *name)
{
symbol_list *p;
if (current_rule->action_props.code)
p = grammar_symbol_append (sym, loc);
if (name)
assign_named_ref(p, name);
+ if (sym->status == undeclared || sym->status == used)
+ sym->status = needed;
}
/* Attach an ACTION to the current rule. */
void
grammar_current_rule_action_append (const char *action, location loc,
- named_ref *name)
+ named_ref *name, bool is_predicate)
{
if (current_rule->action_props.code)
grammar_midrule_action ();
/* After all symbol declarations have been parsed, packgram invokes
code_props_translate_code. */
code_props_rule_action_init (¤t_rule->action_props, action, loc,
- current_rule, name);
+ current_rule, name, is_predicate);
}
\f
int rule_length = 0;
symbol *ruleprec = p->ruleprec;
record_merge_function_type (p->merger, p->content.sym->type_name,
- p->merger_declaration_location);
+ p->merger_declaration_location);
rules[ruleno].user_number = ruleno;
rules[ruleno].number = ruleno;
rules[ruleno].lhs = p->content.sym;
rules[ruleno].useful = true;
rules[ruleno].action = p->action_props.code;
rules[ruleno].action_location = p->action_props.location;
+ rules[ruleno].is_predicate = p->action_props.is_predicate;
/* If the midrule's $$ is set or its $n is used, remove the `$' from the
- symbol name so that it's a user-defined symbol so that the default
- %destructor and %printer apply. */
+ symbol name so that it's a user-defined symbol so that the default
+ %destructor and %printer apply. */
if (p->midrule_parent_rule
&& (p->action_props.is_value_used
- || symbol_list_n_get (p->midrule_parent_rule,
- p->midrule_parent_rhs_index)
+ || symbol_list_n_get (p->midrule_parent_rule,
+ p->midrule_parent_rhs_index)
->action_props.is_value_used))
- p->content.sym->tag += 1;
+ p->content.sym->tag += 1;
/* Don't check the generated rule 0. It has no action, so some rhs
- symbols may appear unused, but the parsing algorithm ensures that
- %destructor's are invoked appropriately. */
+ symbols may appear unused, but the parsing algorithm ensures that
+ %destructor's are invoked appropriately. */
if (p != grammar)
- grammar_rule_check (p);
+ grammar_rule_check (p);
for (p = p->next; p && p->content.sym; p = p->next)
- {
- ++rule_length;
+ {
+ ++rule_length;
- /* Don't allow rule_length == INT_MAX, since that might
- cause confusion with strtol if INT_MAX == LONG_MAX. */
- if (rule_length == INT_MAX)
- fatal_at (rules[ruleno].location, _("rule is too long"));
+ /* Don't allow rule_length == INT_MAX, since that might
+ cause confusion with strtol if INT_MAX == LONG_MAX. */
+ if (rule_length == INT_MAX)
+ complain (&rules[ruleno].location, fatal, _("rule is too long"));
- /* item_number = symbol_number.
- But the former needs to contain more: negative rule numbers. */
- ritem[itemno++] =
+ /* item_number = symbol_number.
+ But the former needs to contain more: negative rule numbers. */
+ ritem[itemno++] =
symbol_number_as_item_number (p->content.sym->number);
- /* A rule gets by default the precedence and associativity
- of its last token. */
- if (p->content.sym->class == token_sym && default_prec)
- rules[ruleno].prec = p->content.sym;
- }
+ /* A rule gets by default the precedence and associativity
+ of its last token. */
+ if (p->content.sym->class == token_sym && default_prec)
+ rules[ruleno].prec = p->content.sym;
+ }
/* If this rule has a %prec,
the specified symbol's precedence replaces the default. */
if (ruleprec)
- {
- rules[ruleno].precsym = ruleprec;
- rules[ruleno].prec = ruleprec;
- }
+ {
+ rules[ruleno].precsym = ruleprec;
+ rules[ruleno].prec = ruleprec;
+ }
/* An item ends by the rule number (negated). */
ritem[itemno++] = rule_number_as_item_number (ruleno);
aver (itemno < ITEM_NUMBER_MAX);
aver (ruleno < RULE_NUMBER_MAX);
if (p)
- p = p->next;
+ p = p->next;
}
aver (itemno == nritems);
gram_parse ();
prepare_percent_define_front_end_variables ();
- if (! complaint_issued)
+ if (complaint_status < status_complaint)
check_and_convert_grammar ();
xfclose (gram_in);
prepare_percent_define_front_end_variables (void)
{
/* Set %define front-end variable defaults. */
- muscle_percent_define_default ("lr.keep-unreachable-states", "false");
+ muscle_percent_define_default ("lr.keep-unreachable-state", "false");
{
char *lr_type;
/* IELR would be a better default, but LALR is historically the
default. */
muscle_percent_define_default ("lr.type", "lalr");
lr_type = muscle_percent_define_get ("lr.type");
- if (0 != strcmp (lr_type, "canonical-lr"))
- muscle_percent_define_default ("lr.default-reductions", "most");
+ if (STRNEQ (lr_type, "canonical-lr"))
+ muscle_percent_define_default ("lr.default-reduction", "most");
else
- muscle_percent_define_default ("lr.default-reductions", "accepting");
+ muscle_percent_define_default ("lr.default-reduction", "accepting");
free (lr_type);
}
{
static char const * const values[] = {
"lr.type", "lalr", "ielr", "canonical-lr", NULL,
- "lr.default-reductions", "most", "consistent", "accepting", NULL,
+ "lr.default-reduction", "most", "consistent", "accepting", NULL,
NULL
};
muscle_percent_define_check_values (values);
/*-------------------------------------------------------------.
| Check the grammar that has just been read, and convert it to |
-| internal form. |
+| internal form. |
`-------------------------------------------------------------*/
static void
{
/* Grammar has been read. Do some checking. */
if (nrules == 0)
- fatal (_("no rules in the input grammar"));
+ complain (NULL, fatal, _("no rules in the input grammar"));
/* If the user did not define her ENDTOKEN, do it now. */
if (!endtoken)
-# Executing Actions. -*- Autotest -*-
+e# Executing Actions. -*- Autotest -*-
# Copyright (C) 2001-2012 Free Software Foundation, Inc.
AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([[input.y]],
-[[%error-verbose
+[[%define parse.error verbose
%debug
%{
]AT_YYERROR_DECLARE[
AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([[input.y]],
-[[%error-verbose
+[[%define parse.error verbose
%debug
%{
]AT_YYERROR_DECLARE[
AT_DATA_GRAMMAR([[input.y]],
[[
%{
-#include <stdio.h>
+# include <stdio.h>
]AT_YYERROR_DECLARE[
]AT_YYLEX_DECLARE[
typedef struct { int val; } stype;
$$ = -1;
V(line, $$, @$, ": ");
V('(', $1, @1, " ");
- fprintf (stderr, "error (@%d-%d) ", RANGE (@2));
+ fprintf (stderr, "error (@%d-%d) ", RANGE(@2));
V(')', $3, @3, "\n");
}
;
$3
_AT_CHECK_PRINTER_AND_DESTRUCTOR($[1], $[2], $[3], $[4],
-[%error-verbose
+[%define parse.error verbose
%debug
%verbose
%locations
AT_CHECK_PRINTER_AND_DESTRUCTOR([])
-AT_CHECK_PRINTER_AND_DESTRUCTOR([], [ with union])
+AT_CHECK_PRINTER_AND_DESTRUCTOR([], [with union])
AT_CHECK_PRINTER_AND_DESTRUCTOR([%defines %skeleton "lalr1.cc"])
-AT_CHECK_PRINTER_AND_DESTRUCTOR([%defines %skeleton "lalr1.cc"], [ with union])
+AT_CHECK_PRINTER_AND_DESTRUCTOR([%defines %skeleton "lalr1.cc"], [with union])
AT_CHECK_PRINTER_AND_DESTRUCTOR([%glr-parser])
-AT_CHECK_PRINTER_AND_DESTRUCTOR([%glr-parser], [ with union])
+AT_CHECK_PRINTER_AND_DESTRUCTOR([%glr-parser], [with union])
AT_SETUP([Default tagless %printer and %destructor])
AT_BISON_OPTION_PUSHDEFS([%locations])
AT_DATA_GRAMMAR([[input.y]],
-[[%error-verbose
+[[%define parse.error verbose
%debug
%locations
}
]])
-AT_BISON_CHECK([-o input.c input.y])
+AT_BISON_CHECK([-o input.c input.y], [], [],
+[[input.y:23.3-5: warning: useless %destructor for type <*> [-Wother]
+input.y:23.3-5: warning: useless %printer for type <*> [-Wother]
+]])
AT_COMPILE([input])
AT_PARSER_CHECK([./input], 1,
[[<> destructor for 'd' @ 4.
AT_SETUP([Default tagged and per-type %printer and %destructor])
AT_BISON_OPTION_PUSHDEFS
AT_DATA_GRAMMAR([[input.y]],
-[[%error-verbose
+[[%define parse.error verbose
%debug
%{
}
]])
-AT_BISON_CHECK([-o input.c input.y])
+AT_BISON_CHECK([-o input.c input.y], [], [],
+[[input.y:22.3-4: warning: useless %destructor for type <> [-Wother]
+input.y:22.3-4: warning: useless %printer for type <> [-Wother]
+]])
AT_COMPILE([input])
AT_PARSER_CHECK([./input], 1,
[[<*>/<field2>/e destructor.
AT_SETUP([Default %printer and %destructor for user-defined end token])
-# _AT_CHECK_DEFAULT_PRINTER_AND_DESTRUCTOR_FOR_END_TOKEN(TYPED)
-# -------------------------------------------------------------
-m4_define([_AT_CHECK_DEFAULT_PRINTER_AND_DESTRUCTOR_FOR_END_TOKEN],
+# AT_TEST(TYPED)
+# --------------
+m4_pushdef([AT_TEST],
[m4_if($1, 0,
[m4_pushdef([kind], []) m4_pushdef([not_kind], [*])],
[m4_pushdef([kind], [*]) m4_pushdef([not_kind], [])])
AT_BISON_OPTION_PUSHDEFS([%locations])
AT_DATA_GRAMMAR([[input]]$1[[.y]],
-[[%error-verbose
+[[%define parse.error verbose
%debug
%locations
]])
AT_BISON_OPTION_POPDEFS
-AT_BISON_CHECK([-o input$1.c input$1.y])
+AT_BISON_CHECK([-o input$1.c input$1.y], [], [],
+[m4_if([$1], [0],
+[[input0.y:23.3-5: warning: useless %destructor for type <*> [-Wother]
+input0.y:23.3-5: warning: useless %printer for type <*> [-Wother]
+]],
+[[input1.y:23.3-4: warning: useless %destructor for type <> [-Wother]
+input1.y:23.3-4: warning: useless %printer for type <> [-Wother]
+]])])
+
AT_COMPILE([input$1])
+
AT_PARSER_CHECK([./input$1], 0,
[[<]]kind[[> for 'E' @ 1.
<]]kind[[> for 'S' @ 1.
m4_popdef([not_kind])
])
-_AT_CHECK_DEFAULT_PRINTER_AND_DESTRUCTOR_FOR_END_TOKEN(0)
-_AT_CHECK_DEFAULT_PRINTER_AND_DESTRUCTOR_FOR_END_TOKEN(1)
+AT_TEST(0)
+AT_TEST(1)
+
+m4_popdef([AT_TEST])
AT_CLEANUP
]])
AT_BISON_OPTION_POPDEFS
-AT_BISON_CHECK([-o input.c input.y])
+AT_BISON_CHECK([-o input.c input.y], [], [],
+[[input.y:21.6-8: warning: useless %destructor for type <*> [-Wother]
+input.y:21.6-8: warning: useless %printer for type <*> [-Wother]
+]])
AT_COMPILE([input])
AT_PARSER_CHECK([./input], [1], [],
[[Starting parse
]])
AT_BISON_OPTION_POPDEFS
-AT_BISON_CHECK([-o input.c input.y])
+AT_BISON_CHECK([-o input.c input.y], [], [],
+[[input.y:22.3-4: warning: useless %destructor for type <> [-Wother]
+input.y:22.3-4: warning: useless %printer for type <> [-Wother]
+]])
AT_COMPILE([input])
AT_CLEANUP
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([-o input.c input.y], 0,,
-[[input.y:33.3-23: warning: unset value: $$
-input.y:32.3-23: warning: unused value: $3
+[[input.y:24.70-72: warning: useless %destructor for type <*> [-Wother]
+input.y:24.70-72: warning: useless %printer for type <*> [-Wother]
+input.y:33.3-23: warning: unset value: $$ [-Wother]
- input.y:30.3-35.37: warning: unused value: $3 [-Wother]
++input.y:32.3-23: warning: unused value: $3 [-Wother]
]])
AT_BISON_CHECK([-fcaret -o input.c input.y], 0,,
-[[input.y:33.3-23: warning: unset value: $$
+[[input.y:24.70-72: warning: useless %destructor for type <*> [-Wother]
+ %printer { fprintf (yyoutput, "<*> printer should not be called"); } <*>
+ ^^^
+input.y:24.70-72: warning: useless %printer for type <*> [-Wother]
+ %printer { fprintf (yyoutput, "<*> printer should not be called"); } <*>
+ ^^^
+input.y:33.3-23: warning: unset value: $$ [-Wother]
{ @$ = 4; } // Only used.
^^^^^^^^^^^^^^^^^^^^^
- input.y:30.3-35.37: warning: unused value: $3 [-Wother]
- { @$ = 1; } // Not set or used.
- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-input.y:32.3-23: warning: unused value: $3
++input.y:32.3-23: warning: unused value: $3 [-Wother]
+ { USE ($$); @$ = 3; } // Only set.
+ ^^^^^^^^^^^^^^^^^^^^^
]])
AT_COMPILE([input])
## Qualified $$ in actions. ##
## ------------------------- ##
-# Check that we can used qualified $$ (v.g., $<type>$) not only in
-# rule actions, but also where $$ is valid: %printer and %destructor.
+# Check that we can use qualified $$ (v.g., $<type>$) not only in rule
+# actions, but also where $$ is valid: %destructor/%printer and
+# %initial-action.
#
# FIXME: Not actually checking %destructor, but it's the same code as
# %printer...
m4_pushdef([AT_TEST],
[AT_SETUP([[Qualified $$ in actions: $1]])
-AT_BISON_OPTION_PUSHDEFS([%locations %skeleton "$1"])
+AT_BISON_OPTION_PUSHDEFS([%skeleton "$1"])
AT_DATA_GRAMMAR([[input.y]],
[[%skeleton "$1"
-%defines // FIXME: Mandated by lalr1.cc in Bison 2.6.
-%locations // FIXME: Mandated by lalr1.cc in Bison 2.6.
%debug
%code requires
{
AT_PARSER_CHECK([./input], 0, [], [stderr])
# Don't be too picky on the traces, GLR is not exactly the same. Keep
# only the lines from the printer.
-#
-# Don't care about locations. FIXME: remove their removal when Bison
-# supports C++ without locations.
-AT_CHECK([[sed -ne 's/([-0-9.]*: /(/;/ival:/p' stderr]], 0,
+AT_CHECK([[sed -ne '/ival:/p' stderr]], 0,
[[Reading a token: Next token is token UNTYPED (ival: 10, fval: 0.1)
Shifting token UNTYPED (ival: 10, fval: 0.1)
Reading a token: Next token is token INT (ival: 20, fval: 0.2)
start: test2 test1 test0 testc;
test2
-: 'a' { semi; /* TEST:N:2 */ }
-| 'b' { if (0) {no_semi} /* TEST:N:2 */ }
-| 'c' { if (0) {semi;} /* TEST:N:2 */ }
-| 'd' { semi; no_semi /* TEST:Y:2 */ }
-| 'e' { semi(); no_semi() /* TEST:Y:2 */ }
-| 'f' { semi[]; no_semi[] /* TEST:Y:2 */ }
-| 'g' { semi++; no_semi++ /* TEST:Y:2 */ }
-| 'h' { {no_semi} no_semi /* TEST:Y:2 */ }
-| 'i' { {semi;} no_semi /* TEST:Y:2 */ }
+: 'a' { semi; /* TEST:N:2 */ }
+| 'b' { if (0) {no_semi} /* TEST:N:2 */ }
+| 'c' { if (0) {semi;} /* TEST:N:2 */ }
+| 'd' { semi; no_semi /* TEST:Y:2 */ }
+| 'e' { semi(); no_semi() /* TEST:Y:2 */ }
+| 'f' { semi[]; no_semi[] /* TEST:Y:2 */ }
+| 'g' { semi++; no_semi++ /* TEST:Y:2 */ }
+| 'h' { {no_semi} no_semi /* TEST:Y:2 */ }
+| 'i' { {semi;} no_semi /* TEST:Y:2 */ }
;
test1
- : 'a' { semi; // TEST:N:1 ;
-} | 'b' { if (0) {no_semi} // TEST:N:1 ;
-} | 'c' { if (0) {semi;} // TEST:N:1 ;
-} | 'd' { semi; no_semi // TEST:Y:1 ;
-} | 'e' { semi(); no_semi() // TEST:Y:1 ;
-} | 'f' { semi[]; no_semi[] // TEST:Y:1 ;
-} | 'g' { semi++; no_semi++ // TEST:Y:1 ;
-} | 'h' { {no_semi} no_semi // TEST:Y:1 ;
-} | 'i' { {semi;} no_semi // TEST:Y:1 ;
+ : 'a' { semi; // TEST:N:1 ;
+} | 'b' { if (0) {no_semi} // TEST:N:1 ;
+} | 'c' { if (0) {semi;} // TEST:N:1 ;
+} | 'd' { semi; no_semi // TEST:Y:1 ;
+} | 'e' { semi(); no_semi() // TEST:Y:1 ;
+} | 'f' { semi[]; no_semi[] // TEST:Y:1 ;
+} | 'g' { semi++; no_semi++ // TEST:Y:1 ;
+} | 'h' { {no_semi} no_semi // TEST:Y:1 ;
+} | 'i' { {semi;} no_semi // TEST:Y:1 ;
} ;
test0
- : 'a' { semi; // TEST:N:1 {}
-} | 'b' { if (0) {no_semi} // TEST:N:1 {}
-} | 'c' { if (0) {semi;} // TEST:N:1 {}
-} | 'd' { semi; no_semi // TEST:Y:1 {}
-} | 'e' { semi(); no_semi() // TEST:Y:1 {}
-} | 'f' { semi[]; no_semi[] // TEST:Y:1 {}
-} | 'g' { semi++; no_semi++ // TEST:Y:1 {}
-} | 'h' { {no_semi} no_semi // TEST:Y:1 {}
-} | 'i' { {semi;} no_semi // TEST:Y:1 {}
+ : 'a' { semi; // TEST:N:1 {}
+} | 'b' { if (0) {no_semi} // TEST:N:1 {}
+} | 'c' { if (0) {semi;} // TEST:N:1 {}
+} | 'd' { semi; no_semi // TEST:Y:1 {}
+} | 'e' { semi(); no_semi() // TEST:Y:1 {}
+} | 'f' { semi[]; no_semi[] // TEST:Y:1 {}
+} | 'g' { semi++; no_semi++ // TEST:Y:1 {}
+} | 'h' { {no_semi} no_semi // TEST:Y:1 {}
+} | 'i' { {semi;} no_semi // TEST:Y:1 {}
} ;
testc
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o input.c input.y]], [0], [],
-[[input.y:8.48: warning: a ';' might be needed at the end of action code
+[[input.y:8.48: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:8.48: future versions of Bison will not add the ';'
-input.y:9.48: warning: a ';' might be needed at the end of action code
+input.y:9.48: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:9.48: future versions of Bison will not add the ';'
-input.y:10.48: warning: a ';' might be needed at the end of action code
+input.y:10.48: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:10.48: future versions of Bison will not add the ';'
-input.y:11.48: warning: a ';' might be needed at the end of action code
+input.y:11.48: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:11.48: future versions of Bison will not add the ';'
-input.y:12.48: warning: a ';' might be needed at the end of action code
+input.y:12.48: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:12.48: future versions of Bison will not add the ';'
-input.y:13.48: warning: a ';' might be needed at the end of action code
+input.y:13.48: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:13.48: future versions of Bison will not add the ';'
-input.y:20.1: warning: a ';' might be needed at the end of action code
+input.y:20.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:20.1: future versions of Bison will not add the ';'
-input.y:21.1: warning: a ';' might be needed at the end of action code
+input.y:21.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:21.1: future versions of Bison will not add the ';'
-input.y:22.1: warning: a ';' might be needed at the end of action code
+input.y:22.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:22.1: future versions of Bison will not add the ';'
-input.y:23.1: warning: a ';' might be needed at the end of action code
+input.y:23.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:23.1: future versions of Bison will not add the ';'
-input.y:24.1: warning: a ';' might be needed at the end of action code
+input.y:24.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:24.1: future versions of Bison will not add the ';'
-input.y:25.1: warning: a ';' might be needed at the end of action code
+input.y:25.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:25.1: future versions of Bison will not add the ';'
-input.y:31.1: warning: a ';' might be needed at the end of action code
+input.y:31.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:31.1: future versions of Bison will not add the ';'
-input.y:32.1: warning: a ';' might be needed at the end of action code
+input.y:32.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:32.1: future versions of Bison will not add the ';'
-input.y:33.1: warning: a ';' might be needed at the end of action code
+input.y:33.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:33.1: future versions of Bison will not add the ';'
-input.y:34.1: warning: a ';' might be needed at the end of action code
+input.y:34.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:34.1: future versions of Bison will not add the ';'
-input.y:35.1: warning: a ';' might be needed at the end of action code
+input.y:35.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:35.1: future versions of Bison will not add the ';'
-input.y:36.1: warning: a ';' might be needed at the end of action code
+input.y:36.1: warning: a ';' might be needed at the end of action code [-Wdeprecated]
input.y:36.1: future versions of Bison will not add the ';'
]])
-# @configure_input@ -*- shell-script -*-
+# @configure_input@ -*- shell-script -*-
# Configurable variable values for Bison test suite.
# Copyright (C) 2000-2012 Free Software Foundation, Inc.
# We need `config.h'.
CPPFLAGS="-I$abs_top_builddir/lib @CPPFLAGS@"
+ # Don't just check if $POSIXLY_CORRECT is set, as Bash, when launched
+ # as /bin/sh, sets the shell variable POSIXLY_CORRECT to y, but not
+ # the environment variable.
+ if env | grep '^POSIXLY_CORRECT=' >/dev/null; then
+ POSIXLY_CORRECT_IS_EXPORTED=true
+ else
+ POSIXLY_CORRECT_IS_EXPORTED=false
+ fi
+
## ------------------- ##
## C/C++ Compilation. ##
## ------------------- ##
CFLAGS="$NO_WERROR_CFLAGS @WERROR_CFLAGS@"
CXXFLAGS="$NO_WERROR_CXXFLAGS @WERROR_CXXFLAGS@"
-# If 'exit 77'; skip all C/C++ tests; otherwise ':'.
-BISON_C_WORKS='@BISON_C_WORKS@'
+# C++ variants break strict aliasing analysis.
+NO_STRICT_ALIAS_CXXFLAGS='@NO_STRICT_ALIAS_CXXFLAGS@'
+
+# If 'exit 77'; skip all C++ tests; otherwise ':'.
BISON_CXX_WORKS='@BISON_CXX_WORKS@'
+ # Whether the compiler supports POSIXLY_CORRECT defined.
+ : ${C_COMPILER_POSIXLY_CORRECT='@C_COMPILER_POSIXLY_CORRECT@'}
+ : ${CXX_COMPILER_POSIXLY_CORRECT='@CXX_COMPILER_POSIXLY_CORRECT@'}
+
+ if $POSIXLY_CORRECT_IS_EXPORTED; then
+ $C_COMPILER_POSIXLY_CORRECT ||
+ BISON_C_WORKS="as_fn_error 77 POSIXLY_CORRECT"
+ $CXX_COMPILER_POSIXLY_CORRECT ||
+ BISON_CXX_WORKS="as_fn_error 77 POSIXLY_CORRECT"
+ fi
+
# Handle --compile-c-with-cxx here, once CXX and CXXFLAGS are known.
if "$at_arg_compile_c_with_cxx"; then
CC_IS_CXX=1
CC=$CXX
NO_WERROR_CFLAGS=$NO_WERROR_CXXFLAGS
CFLAGS=$CXXFLAGS
+ BISON_C_WORKS=$BISON_CXX_WORKS
else
CC_IS_CXX=0
fi
# Empty if no Java VM was found
CONF_JAVA='@CONF_JAVA@'
-# We need egrep.
+# We need egrep and perl.
: ${EGREP='@EGREP@'}
+: ${PERL='@PERL@'}
# Use simple quotes (lib/quote.c).
LC_CTYPE=C
# Empty if no xsltproc was found
: ${XSLTPROC='@XSLTPROC@'}
-: ${PERL='@PERL@'}
+# Don't just check if $POSIXLY_CORRECT is set, as Bash, when launched
+# as /bin/sh, sets the shell variable POSIXLY_CORRECT to y, but not
+# the environment variable.
+: ${C_COMPILER_POSIXLY_CORRECT='@C_COMPILER_POSIXLY_CORRECT@'}
+if env | grep '^POSIXLY_CORRECT=' >/dev/null; then
+ POSIXLY_CORRECT_IS_EXPORTED=true
+else
+ POSIXLY_CORRECT_IS_EXPORTED=false
+fi
AT_BANNER([[GLR Regression Tests]])
- ## --------------------------- ##
- ## Badly Collapsed GLR States. ##
- ## --------------------------- ##
+ ## ---------------------------- ##
+ ## Badly Collapsed GLR States. ##
+ ## ---------------------------- ##
AT_SETUP([Badly Collapsed GLR States])
return 0;
}
- const char *input = NULL;
+ const char *input = YY_NULL;
int
main (int argc, const char* argv[])
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr1.c glr-regr1.y]], 0, [],
-[glr-regr1.y: conflicts: 1 shift/reduce
-])
+[[glr-regr1.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
+]])
AT_COMPILE([glr-regr1])
AT_PARSER_CHECK([[./glr-regr1 BPBPB]], 0,
[[E -> 'B'
AT_CLEANUP
- ## ------------------------------------------------------------ ##
- ## Improper handling of embedded actions and $-N in GLR parsers ##
- ## ------------------------------------------------------------ ##
+ ## -------------------------------------------------------------- ##
+ ## Improper handling of embedded actions and $-N in GLR parsers. ##
+ ## -------------------------------------------------------------- ##
AT_SETUP([Improper handling of embedded actions and dollar(-N) in GLR parsers])
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr2a.c glr-regr2a.y]], 0, [],
-[glr-regr2a.y: conflicts: 2 shift/reduce
-])
+[[glr-regr2a.y: warning: 2 shift/reduce conflicts [-Wconflicts-sr]
+]])
AT_COMPILE([glr-regr2a])
AT_DATA([input1.txt],
AT_CLEANUP
- ## ------------------------------------------------------------ ##
- ## Improper merging of GLR delayed action sets ##
- ## ------------------------------------------------------------ ##
+ ## --------------------------------------------- ##
+ ## Improper merging of GLR delayed action sets. ##
+ ## --------------------------------------------- ##
AT_SETUP([Improper merging of GLR delayed action sets])
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr3.c glr-regr3.y]], 0, [],
-[glr-regr3.y: conflicts: 1 shift/reduce, 1 reduce/reduce
-])
+[[glr-regr3.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
+glr-regr3.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr3])
AT_DATA([input.txt],
AT_CLEANUP
- ## ------------------------------------------------------------------------- ##
- ## Duplicate representation of merged trees. See ##
- ## <http://lists.gnu.org/archive/html/help-bison/2005-07/msg00013.html>. ##
- ## ------------------------------------------------------------------------- ##
+ ## ---------------------------------------------------------------------- ##
+ ## Duplicate representation of merged trees. See ##
+ ## <http://lists.gnu.org/archive/html/help-bison/2005-07/msg00013.html>. ##
+ ## ---------------------------------------------------------------------- ##
AT_SETUP([Duplicate representation of merged trees])
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr4.c glr-regr4.y]], 0, [],
-[glr-regr4.y: conflicts: 1 reduce/reduce
-])
+[[glr-regr4.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr4])
AT_PARSER_CHECK([[./glr-regr4]], 0,
AT_CLEANUP
- ## -------------------------------------------------------------------------- ##
- ## User destructor for unresolved GLR semantic value. See ##
- ## <http://lists.gnu.org/archive/html/bison-patches/2005-08/msg00016.html>. ##
- ## -------------------------------------------------------------------------- ##
+ ## ------------------------------------------------------------------------- ##
+ ## User destructor for unresolved GLR semantic value. See ##
+ ## <http://lists.gnu.org/archive/html/bison-patches/2005-08/msg00016.html>. ##
+ ## ------------------------------------------------------------------------- ##
AT_SETUP([User destructor for unresolved GLR semantic value])
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr5.c glr-regr5.y]], 0, [],
-[glr-regr5.y: conflicts: 1 reduce/reduce
-])
+[[glr-regr5.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr5])
AT_PARSER_CHECK([[./glr-regr5]], 0, [],
AT_CLEANUP
- ## -------------------------------------------------------------------------- ##
- ## User destructor after an error during a split parse. See ##
- ## <http://lists.gnu.org/archive/html/bison-patches/2005-08/msg00029.html>. ##
- ## -------------------------------------------------------------------------- ##
+ ## ------------------------------------------------------------------------- ##
+ ## User destructor after an error during a split parse. See ##
+ ## <http://lists.gnu.org/archive/html/bison-patches/2005-08/msg00029.html>. ##
+ ## ------------------------------------------------------------------------- ##
AT_SETUP([User destructor after an error during a split parse])
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr6.c glr-regr6.y]], 0, [],
-[glr-regr6.y: conflicts: 1 reduce/reduce
-])
+[[glr-regr6.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr6])
AT_PARSER_CHECK([[./glr-regr6]], 0,
## ------------------------------------------------------------------------- ##
- ## Duplicated user destructor for lookahead. See ##
+ ## Duplicated user destructor for lookahead. See ##
## <http://lists.gnu.org/archive/html/bison-patches/2005-08/msg00035.html>. ##
## ------------------------------------------------------------------------- ##
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr7.c glr-regr7.y]], 0, [],
-[glr-regr7.y: conflicts: 2 reduce/reduce
-])
+[[glr-regr7.y: warning: 2 reduce/reduce conflicts [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr7])
AT_PARSER_CHECK([[./glr-regr7]], 2, [],
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr8.c glr-regr8.y]], 0, [],
-[glr-regr8.y: conflicts: 1 reduce/reduce
-])
+[[glr-regr8.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr8])
AT_PARSER_CHECK([[./glr-regr8]], 0,
## ------------------------------------------------------------------------- ##
- ## No users destructors if stack 0 deleted. See ##
+ ## No users destructors if stack 0 deleted. See ##
## <http://lists.gnu.org/archive/html/bison-patches/2005-09/msg00109.html>. ##
## ------------------------------------------------------------------------- ##
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr9.c glr-regr9.y]], 0, [],
-[glr-regr9.y: conflicts: 1 reduce/reduce
-])
+[[glr-regr9.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr9])
AT_PARSER_CHECK([[./glr-regr9]], 0, [],
AT_CLEANUP
- ## ------------------------------------------------------------------------- ##
- ## Corrupted semantic options if user action cuts parse. ##
- ## ------------------------------------------------------------------------- ##
+ ## ------------------------------------------------------ ##
+ ## Corrupted semantic options if user action cuts parse. ##
+ ## ------------------------------------------------------ ##
AT_SETUP([Corrupted semantic options if user action cuts parse])
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr10.c glr-regr10.y]], 0, [],
-[glr-regr10.y: conflicts: 1 reduce/reduce
-])
+[[glr-regr10.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr10])
AT_PARSER_CHECK([[./glr-regr10]], 0, [], [])
AT_CLEANUP
- ## ------------------------------------------------------------------------- ##
- ## Undesirable destructors if user action cuts parse. ##
- ## ------------------------------------------------------------------------- ##
+ ## --------------------------------------------------- ##
+ ## Undesirable destructors if user action cuts parse. ##
+ ## --------------------------------------------------- ##
AT_SETUP([Undesirable destructors if user action cuts parse])
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr11.c glr-regr11.y]], 0, [],
-[glr-regr11.y: conflicts: 1 reduce/reduce
-])
+[[glr-regr11.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr11])
AT_PARSER_CHECK([[./glr-regr11]], 0, [], [])
AT_CLEANUP
- ## ------------------------------------------------------------------------- ##
- ## Leaked semantic values if user action cuts parse. ##
- ## ------------------------------------------------------------------------- ##
+ ## -------------------------------------------------- ##
+ ## Leaked semantic values if user action cuts parse. ##
+ ## -------------------------------------------------- ##
AT_SETUP([Leaked semantic values if user action cuts parse])
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr12.c glr-regr12.y]], 0, [],
-[glr-regr12.y: conflicts: 1 shift/reduce, 1 reduce/reduce
-])
+[[glr-regr12.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
+glr-regr12.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr12])
AT_PARSER_CHECK([[./glr-regr12]], 0, [], [])
AT_CLEANUP
- ## ------------------------------------------------------------------------- ##
- ## Incorrect lookahead during nondeterministic GLR. ##
- ## ------------------------------------------------------------------------- ##
+ ## ------------------------------------------------- ##
+ ## Incorrect lookahead during nondeterministic GLR. ##
+ ## ------------------------------------------------- ##
AT_SETUP([Incorrect lookahead during nondeterministic GLR])
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr14.c glr-regr14.y]], 0, [],
-[glr-regr14.y: conflicts: 3 reduce/reduce
-])
+[[glr-regr14.y: warning: 3 reduce/reduce conflicts [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr14])
AT_PARSER_CHECK([[./glr-regr14]], 0,
AT_CLEANUP
- ## ------------------------------------------------------------------------- ##
- ## Leaked semantic values when reporting ambiguity. ##
- ## ------------------------------------------------------------------------- ##
+ ## ------------------------------------------------- ##
+ ## Leaked semantic values when reporting ambiguity. ##
+ ## ------------------------------------------------- ##
AT_SETUP([Leaked semantic values when reporting ambiguity])
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr15.c glr-regr15.y]], 0, [],
-[glr-regr15.y: conflicts: 2 reduce/reduce
-])
+[[glr-regr15.y: warning: 2 reduce/reduce conflicts [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr15])
AT_PARSER_CHECK([[./glr-regr15]], 0, [],
AT_CLEANUP
- ## ------------------------------------------------------------------------- ##
- ## Leaked lookahead after nondeterministic parse syntax error. ##
- ## ------------------------------------------------------------------------- ##
+ ## ------------------------------------------------------------ ##
+ ## Leaked lookahead after nondeterministic parse syntax error. ##
+ ## ------------------------------------------------------------ ##
AT_SETUP([Leaked lookahead after nondeterministic parse syntax error])
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr16.c glr-regr16.y]], 0, [],
-[glr-regr16.y: conflicts: 1 reduce/reduce
-])
+[[glr-regr16.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr16])
AT_PARSER_CHECK([[./glr-regr16]], 0, [],
AT_CLEANUP
- ## ------------------------------------------------------------------------- ##
- ## Uninitialized location when reporting ambiguity. ##
- ## ------------------------------------------------------------------------- ##
+ ## ------------------------------------------------- ##
+ ## Uninitialized location when reporting ambiguity. ##
+ ## ------------------------------------------------- ##
AT_SETUP([Uninitialized location when reporting ambiguity])
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr17.c glr-regr17.y]], 0, [],
-[glr-regr17.y: conflicts: 3 reduce/reduce
-])
+[[glr-regr17.y: warning: 3 reduce/reduce conflicts [-Wconflicts-rr]
+]])
AT_COMPILE([glr-regr17])
AT_PARSER_CHECK([[./glr-regr17]], 0, [],
AT_CLEANUP
- ## -------------------------------------------------------------##
- ## Missed %merge type warnings when LHS type is declared later. ##
- ## -------------------------------------------------------------##
+ ## ------------------------------------------------------------- ##
+ ## Missed %merge type warnings when LHS type is declared later. ##
+ ## ------------------------------------------------------------- ##
AT_SETUP([Missed %merge type warnings when LHS type is declared later])
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o glr-regr18.c glr-regr18.y]], 1, [],
-[glr-regr18.y:26.18-24: error: result type clash on merge function 'merge': <type2> != <type1>
+[[glr-regr18.y:26.18-24: error: result type clash on merge function 'merge': <type2> != <type1>
glr-regr18.y:25.18-24: previous declaration
glr-regr18.y:27.13-19: error: result type clash on merge function 'merge': <type3> != <type2>
glr-regr18.y:26.18-24: previous declaration
-])
+]])
AT_CLEANUP
AT_BISON_OPTION_POPDEFS
AT_BISON_CHECK([[-o input.c input.y]], 0, [],
-[input.y: conflicts: 1 reduce/reduce
-])
+[[input.y: warning: 1 reduce/reduce conflict [-Wconflicts-rr]
+]])
AT_COMPILE([input])
AT_PARSER_CHECK([[./input]], 1, [],
AT_BISON_CHECK([input.y], [1], [],
[[input.y:5.12-13: error: $$ for the midrule at $2 of 'exp' has no declared type
input.y:5.24-25: error: $2 of 'exp' has no declared type
-input.y:5.6-32: warning: type clash on default action: <bar> != <>
-input.y:6.6-8: warning: type clash on default action: <bar> != <>
-input.y:7.5: warning: empty rule for typed nonterminal, and no action
+input.y:5.6-32: warning: type clash on default action: <bar> != <> [-Wother]
+input.y:6.6-8: warning: type clash on default action: <bar> != <> [-Wother]
+input.y:7.5: warning: empty rule for typed nonterminal, and no action [-Wother]
]])
AT_CLEANUP
# --------------------------------
# Generate the token, type, and destructor
# declarations for the unused values tests.
-
m4_define([_AT_UNUSED_VALUES_DECLARATIONS],
[[[%token <integer> INT;
%type <integer> a b c d e f g h i j k l;
# AT_CHECK_UNUSED_VALUES(DECLARATIONS_AFTER, CHECK_MIDRULE_VALUES)
-# ------------------------------------------------------------------
-# Generate a grammar to test unused values,
-# compile it, run it. If DECLARATIONS_AFTER
-# is set, then the token, type, and destructor
-# declarations are generated after the rules
-# rather than before. If CHECK_MIDRULE_VALUES
-# is set, then --warnings=midrule-values is
-# set.
-
+# ----------------------------------------------------------------
+# Generate a grammar to test unused values, compile it, run it. If
+# DECLARATIONS_AFTER is set, then the token, type, and destructor
+# declarations are generated after the rules rather than before. If
+# CHECK_MIDRULE_VALUES is set, then --warnings=midrule-values is set.
m4_define([AT_CHECK_UNUSED_VALUES],
[AT_DATA([input.y],
m4_ifval($1, [
_AT_UNUSED_VALUES_DECLARATIONS])
)
- AT_BISON_CHECK(m4_ifval($2, [ --warnings=midrule-values ])[ input.y], [0], [],
- [[input.y:11.10-32: warning: unset value: $]$[ [-Wother]
- input.y:11.10-32: warning: unused value: $]1[ [-Wother]
- input.y:11.10-32: warning: unused value: $]3[ [-Wother]
- input.y:11.10-32: warning: unused value: $]5[ [-Wother]
+ AT_BISON_CHECK(m4_ifval($2, [--warnings=midrule-values ])[-fcaret input.y],
+ [0], [],
-[[input.y:11.10-32: warning: unset value: $][$
++[[input.y:11.10-32: warning: unset value: $][$ [-Wother]
+ a: INT | INT { } INT { } INT { };
+ ^^^^^^^^^^^^^^^^^^^^^^^
-input.y:11.10-12: warning: unused value: $][1
++input.y:11.10-12: warning: unused value: $][1 [-Wother]
+ a: INT | INT { } INT { } INT { };
+ ^^^
-input.y:11.18-20: warning: unused value: $][3
++input.y:11.18-20: warning: unused value: $][3 [-Wother]
+ a: INT | INT { } INT { } INT { };
+ ^^^
-input.y:11.26-28: warning: unused value: $][5
++input.y:11.26-28: warning: unused value: $][5 [-Wother]
+ a: INT | INT { } INT { } INT { };
+ ^^^
-input.y:12.9: warning: empty rule for typed nonterminal, and no action
+input.y:12.9: warning: empty rule for typed nonterminal, and no action [-Wother]
- ]]m4_ifval($2, [[[input.y:13.14-20: warning: unset value: $$ [-Wmidrule-values]
- input.y:13.26-41: warning: unset value: $$ [-Wmidrule-values]
- ]]])[[input.y:13.10-62: warning: unset value: $]$[ [-Wother]
- input.y:13.10-62: warning: unused value: $]3[ [-Wother]
- input.y:13.10-62: warning: unused value: $]5[ [-Wother]
- ]]m4_ifval($2, [[[input.y:14.14-16: warning: unset value: $$ [-Wmidrule-values]
- ]]])[[input.y:14.10-49: warning: unset value: $]$[ [-Wother]
- input.y:14.10-49: warning: unused value: $]3[ [-Wother]
- input.y:14.10-49: warning: unused value: $]5[ [-Wother]
- input.y:15.10-37: warning: unset value: $]$[ [-Wother]
- input.y:15.10-37: warning: unused value: $]3[ [-Wother]
- input.y:15.10-37: warning: unused value: $]5[ [-Wother]
- input.y:17.10-58: warning: unset value: $]$[ [-Wother]
- input.y:17.10-58: warning: unused value: $]1[ [-Wother]
- ]]m4_ifval($2, [[[input.y:17.10-58: warning: unused value: $]2[ [-Wmidrule-values]
- ]]])[[input.y:17.10-58: warning: unused value: $]3[ [-Wother]
- ]]m4_ifval($2, [[[input.y:17.10-58: warning: unused value: $]4[ [-Wmidrule-values]
- ]]])[[input.y:17.10-58: warning: unused value: $]5[ [-Wother]
- input.y:18.10-72: warning: unset value: $]$[ [-Wother]
- input.y:18.10-72: warning: unused value: $]1[ [-Wother]
- input.y:18.10-72: warning: unused value: $]3[ [-Wother]
- ]]m4_ifval($2, [[[input.y:18.10-72: warning: unused value: $]4[ [-Wmidrule-values]
- ]]])[[input.y:18.10-72: warning: unused value: $]5[ [-Wother]
- ]]m4_ifval($2, [[[input.y:20.10-55: warning: unused value: $]3[ [-Wmidrule-values]
- ]]])[[input.y:21.10-68: warning: unset value: $]$[ [-Wother]
- input.y:21.10-68: warning: unused value: $]1[ [-Wother]
- input.y:21.10-68: warning: unused value: $]2[ [-Wother]
- ]]m4_ifval($2, [[[input.y:21.10-68: warning: unused value: $]4[ [-Wmidrule-values]
- ]]]))])
-
+ b: INT | /* empty */;
+ ^
-]]m4_ifval($2, [[[input.y:13.14-20: warning: unset value: $][$
++]]m4_ifval($2, [[[input.y:13.14-20: warning: unset value: $][$ [-Wmidrule-values]
+ c: INT | INT { $][1; } INT { $<integer>2; } INT { $<integer>4; };
+ ^^^^^^^
-input.y:13.26-41: warning: unset value: $][$
++input.y:13.26-41: warning: unset value: $][$ [-Wmidrule-values]
+ c: INT | INT { $][1; } INT { $<integer>2; } INT { $<integer>4; };
+ ^^^^^^^^^^^^^^^^
-]]])[[input.y:13.10-62: warning: unset value: $][$
++]]])[[input.y:13.10-62: warning: unset value: $][$ [-Wother]
+ c: INT | INT { $][1; } INT { $<integer>2; } INT { $<integer>4; };
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-input.y:13.22-24: warning: unused value: $][3
++input.y:13.22-24: warning: unused value: $][3 [-Wother]
+ c: INT | INT { $][1; } INT { $<integer>2; } INT { $<integer>4; };
+ ^^^
-input.y:13.43-45: warning: unused value: $][5
++input.y:13.43-45: warning: unused value: $][5 [-Wother]
+ c: INT | INT { $][1; } INT { $<integer>2; } INT { $<integer>4; };
+ ^^^
-]]m4_ifval($2, [[[input.y:14.14-16: warning: unset value: $][$
++]]m4_ifval($2, [[[input.y:14.14-16: warning: unset value: $][$ [-Wmidrule-values]
+ d: INT | INT { } INT { $][1; } INT { $<integer>2; };
+ ^^^
-]]])[[input.y:14.10-49: warning: unset value: $][$
++]]])[[input.y:14.10-49: warning: unset value: $][$ [-Wother]
+ d: INT | INT { } INT { $][1; } INT { $<integer>2; };
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-input.y:14.18-20: warning: unused value: $][3
++input.y:14.18-20: warning: unused value: $][3 [-Wother]
+ d: INT | INT { } INT { $][1; } INT { $<integer>2; };
+ ^^^
-input.y:14.30-32: warning: unused value: $][5
++input.y:14.30-32: warning: unused value: $][5 [-Wother]
+ d: INT | INT { } INT { $][1; } INT { $<integer>2; };
+ ^^^
-input.y:15.10-37: warning: unset value: $][$
++input.y:15.10-37: warning: unset value: $][$ [-Wother]
+ e: INT | INT { } INT { } INT { $][1; };
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-input.y:15.18-20: warning: unused value: $][3
++input.y:15.18-20: warning: unused value: $][3 [-Wother]
+ e: INT | INT { } INT { } INT { $][1; };
+ ^^^
-input.y:15.27-29: warning: unused value: $][5
++input.y:15.27-29: warning: unused value: $][5 [-Wother]
+ e: INT | INT { } INT { } INT { $][1; };
+ ^^^
-input.y:17.10-58: warning: unset value: $][$
++input.y:17.10-58: warning: unset value: $][$ [-Wother]
+ g: INT | INT { $<integer>$; } INT { $<integer>$; } INT { };
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-input.y:17.10-12: warning: unused value: $][1
++input.y:17.10-12: warning: unused value: $][1 [-Wother]
+ g: INT | INT { $<integer>$; } INT { $<integer>$; } INT { };
+ ^^^
-]]m4_ifval($2, [[[input.y:17.14-29: warning: unused value: $][2
++]]m4_ifval($2, [[[input.y:17.14-29: warning: unused value: $][2 [-Wmidrule-values]
+ g: INT | INT { $<integer>$; } INT { $<integer>$; } INT { };
+ ^^^^^^^^^^^^^^^^
-]]])[[input.y:17.31-33: warning: unused value: $][3
++]]])[[input.y:17.31-33: warning: unused value: $][3 [-Wother]
+ g: INT | INT { $<integer>$; } INT { $<integer>$; } INT { };
+ ^^^
-]]m4_ifval($2, [[[input.y:17.35-50: warning: unused value: $][4
++]]m4_ifval($2, [[[input.y:17.35-50: warning: unused value: $][4 [-Wmidrule-values]
+ g: INT | INT { $<integer>$; } INT { $<integer>$; } INT { };
+ ^^^^^^^^^^^^^^^^
-]]])[[input.y:17.52-54: warning: unused value: $][5
++]]])[[input.y:17.52-54: warning: unused value: $][5 [-Wother]
+ g: INT | INT { $<integer>$; } INT { $<integer>$; } INT { };
+ ^^^
-input.y:18.10-72: warning: unset value: $][$
++input.y:18.10-72: warning: unset value: $][$ [-Wother]
+ h: INT | INT { $<integer>$; } INT { $<integer>$ = $<integer>2; } INT { };
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-input.y:18.10-12: warning: unused value: $][1
++input.y:18.10-12: warning: unused value: $][1 [-Wother]
+ h: INT | INT { $<integer>$; } INT { $<integer>$ = $<integer>2; } INT { };
+ ^^^
-input.y:18.31-33: warning: unused value: $][3
++input.y:18.31-33: warning: unused value: $][3 [-Wother]
+ h: INT | INT { $<integer>$; } INT { $<integer>$ = $<integer>2; } INT { };
+ ^^^
-]]m4_ifval($2, [[[input.y:18.35-64: warning: unused value: $][4
++]]m4_ifval($2, [[[input.y:18.35-64: warning: unused value: $][4 [-Wmidrule-values]
+ h: INT | INT { $<integer>$; } INT { $<integer>$ = $<integer>2; } INT { };
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-]]])[[input.y:18.66-68: warning: unused value: $][5
++]]])[[input.y:18.66-68: warning: unused value: $][5 [-Wother]
+ h: INT | INT { $<integer>$; } INT { $<integer>$ = $<integer>2; } INT { };
+ ^^^
-]]m4_ifval($2, [[[input.y:20.18-37: warning: unused value: $][3
++]]m4_ifval($2, [[[input.y:20.18-37: warning: unused value: $][3 [-Wmidrule-values]
+ j: INT | INT INT { $<integer>$ = 1; } { $][$ = $][1 + $][2; };
+ ^^^^^^^^^^^^^^^^^^^^
-]]])[[input.y:21.10-68: warning: unset value: $][$
++]]])[[input.y:21.10-68: warning: unset value: $][$ [-Wother]
+ k: INT | INT INT { $<integer>$; } { $<integer>$ = $<integer>3; } { };
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-input.y:21.10-12: warning: unused value: $][1
++input.y:21.10-12: warning: unused value: $][1 [-Wother]
+ k: INT | INT INT { $<integer>$; } { $<integer>$ = $<integer>3; } { };
+ ^^^
-input.y:21.14-16: warning: unused value: $][2
++input.y:21.14-16: warning: unused value: $][2 [-Wother]
+ k: INT | INT INT { $<integer>$; } { $<integer>$ = $<integer>3; } { };
+ ^^^
-]]m4_ifval($2, [[[input.y:21.35-64: warning: unused value: $][4
++]]m4_ifval($2, [[[input.y:21.35-64: warning: unused value: $][4 [-Wmidrule-values]
+ k: INT | INT INT { $<integer>$; } { $<integer>$ = $<integer>3; } { };
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+ ]]]))
+ ])
## --------------- ##
## Unused values. ##
]])
AT_BISON_CHECK([input.y], [1], [],
-[[input.y:1.13-29: error: redeclaration for default tagged %destructor
+[[input.y:1.13-29: error: %destructor redeclaration for <*>
input.y:1.13-29: previous declaration
-input.y:2.10-24: error: redeclaration for default tagged %printer
+input.y:2.10-24: error: %printer redeclaration for <*>
input.y:2.10-24: previous declaration
-input.y:4.13-29: error: redeclaration for default tagged %destructor
+input.y:4.13-29: error: %destructor redeclaration for <*>
input.y:1.13-29: previous declaration
-input.y:5.10-24: error: redeclaration for default tagged %printer
+input.y:5.10-24: error: %printer redeclaration for <*>
input.y:2.10-24: previous declaration
-input.y:7.13-29: error: redeclaration for default tagless %destructor
+input.y:7.13-29: error: %destructor redeclaration for <>
input.y:7.13-29: previous declaration
-input.y:8.10-24: error: redeclaration for default tagless %printer
+input.y:8.10-24: error: %printer redeclaration for <>
input.y:8.10-24: previous declaration
-input.y:10.13-29: error: redeclaration for default tagless %destructor
+input.y:10.13-29: error: %destructor redeclaration for <>
input.y:7.13-29: previous declaration
-input.y:11.10-24: error: redeclaration for default tagless %printer
+input.y:11.10-24: error: %printer redeclaration for <>
input.y:8.10-24: previous declaration
-input.y:17.13-29: error: redeclaration for default tagged %destructor
+input.y:17.13-29: error: %destructor redeclaration for <*>
input.y:4.13-29: previous declaration
-input.y:18.10-24: error: redeclaration for default tagged %printer
+input.y:18.10-24: error: %printer redeclaration for <*>
input.y:5.10-24: previous declaration
-input.y:20.13-29: error: redeclaration for default tagless %destructor
+input.y:20.13-29: error: %destructor redeclaration for <>
input.y:10.13-29: previous declaration
-input.y:21.10-24: error: redeclaration for default tagless %printer
+input.y:21.10-24: error: %printer redeclaration for <>
input.y:11.10-24: previous declaration
]])
AT_CLEANUP
+## ------------------- ##
+## Undefined symbols. ##
+## ------------------- ##
+
+AT_SETUP([Undefined symbols])
+
+AT_DATA([[input.y]],
+[[%printer {} foo baz
+%destructor {} bar
+%type <foo> qux
+%%
+exp: bar;
+]])
+
+AT_BISON_CHECK([input.y], [1], [],
+[[input.y:2.16-18: error: symbol bar is used, but is not defined as a token and has no rules
+input.y:1.17-19: warning: symbol baz is used, but is not defined as a token and has no rules [-Wother]
+input.y:1.13-15: warning: symbol foo is used, but is not defined as a token and has no rules [-Wother]
+input.y:3.13-15: warning: symbol qux is used, but is not defined as a token and has no rules [-Wother]
+]])
+
+AT_CLEANUP
+
+
+## ----------------------------------------------------- ##
+## Unassociated types used for a printer or destructor. ##
+## ----------------------------------------------------- ##
+
+AT_SETUP([Unassociated types used for a printer or destructor])
+
+AT_DATA([[input.y]],
+[[%token <type1> tag1
+%type <type2> tag2
+
+%printer { } <type1> <type3>
+%destructor { } <type2> <type4>
+
+%%
+
+exp: tag1 { $1; }
+ | tag2 { $1; }
+
+tag2: "a" { $$; }
+]])
+
+AT_BISON_CHECK([input.y], [0], [],
+[[input.y:4.22-28: warning: type <type3> is used, but is not associated to any symbol [-Wother]
+input.y:5.25-31: warning: type <type4> is used, but is not associated to any symbol [-Wother]
+]])
+
+AT_CLEANUP
+
+
+## --------------------------------- ##
+## Useless printers or destructors. ##
+## --------------------------------- ##
+
+AT_SETUP([Useless printers or destructors])
+
+# AT_TEST([INPUT], [STDERR])
+# --------------------------
+m4_pushdef([AT_TEST],
+[AT_DATA([[input.y]],
+[$1
+])
+AT_BISON_CHECK([input.y], [0], [], [$2
+])])
+
+AT_TEST([[%token <type1> token1
+%token <type2> token2
+%token <type3> token3
+%token <type4> token4
+%token <type5> token51 token52
+%token <type6> token61 token62
+%token <type7> token7
+
+%printer {} token1
+%destructor {} token2
+%printer {} token51
+%destructor {} token61
+
+%printer {} token7
+
+%printer {} <type1>
+%destructor {} <type2>
+%printer {} <type3>
+%destructor {} <type4>
+
+%printer {} <type5>
+%destructor {} <type6>
+
+%destructor {} <type7>
+
+%%
+exp: "a";]],
+[[input.y:16.13-19: warning: useless %printer for type <type1> [-Wother]
+input.y:17.16-22: warning: useless %destructor for type <type2> [-Wother]]])
+
+# If everybody is typed, <> is useless.
+AT_TEST([[%type <type> exp
+%token <type> a
+%printer {} <> <*>
+%%
+exp: a;]],
+[[input.y:3.13-14: warning: useless %printer for type <> [-Wother]]])
+
+# If nobody is typed, <*> is useless.
+AT_TEST([[%token a
+%printer {} <> <*>
+%%
+exp: a;]],
+[[input.y:2.16-18: warning: useless %printer for type <*> [-Wother]]])
+
+m4_popdef([AT_TEST])
+
+AT_CLEANUP
+
## ---------------------------------------- ##
## Unused values with default %destructor. ##
]])
AT_BISON_CHECK([input.y], [0], [],
-[[input.y:6.8-45: warning: unset value: $$
-input.y:6.12-14: warning: unused value: $2
-input.y:7.6-8: warning: unset value: $$
+[[input.y:6.8-45: warning: unset value: $$ [-Wother]
- input.y:6.8-45: warning: unused value: $2 [-Wother]
++input.y:6.12-14: warning: unused value: $2 [-Wother]
+input.y:7.6-8: warning: unset value: $$ [-Wother]
]])
AT_DATA([[input.y]],
]])
AT_BISON_CHECK([input.y], [0], [],
- [[input.y:6.8-45: warning: unused value: $4 [-Wother]
-[[input.y:6.23-28: warning: unused value: $4
-input.y:8.9-11: warning: unset value: $$
++[[input.y:6.23-28: warning: unused value: $4 [-Wother]
+input.y:8.9-11: warning: unset value: $$ [-Wother]
]])
AT_CLEANUP
]])
AT_BISON_CHECK([input.y], [0], [],
-[[input.y:6.8-22: warning: unset value: $$
-input.y:6.12-14: warning: unused value: $2
-input.y:7.6-8: warning: unset value: $$
+[[input.y:6.8-22: warning: unset value: $$ [-Wother]
- input.y:6.8-22: warning: unused value: $2 [-Wother]
++input.y:6.12-14: warning: unused value: $2 [-Wother]
+input.y:7.6-8: warning: unset value: $$ [-Wother]
]])
AT_CLEANUP
}
]])
-# Pacify Emacs' font-lock-mode: "
+# Pacify Emacs'font-lock-mode: "
AT_DATA([main.c],
[[typedef int value;
AT_SETUP([String aliases for character tokens])
-# Bison once thought a character token and its alias were different symbols
-# with the same user token number.
+# Bison once thought a character token and its alias were different
+# symbols with the same user token number.
AT_DATA_GRAMMAR([input.y],
[[%token 'a' "a"
AT_BISON_OPTION_POPDEFS
# POSIX Yacc accept periods, but not dashes.
-AT_BISON_CHECK([--yacc input.y], [1], [],
-[[input.y:9.8-16: POSIX Yacc forbids dashes in symbol names: WITH-DASH
-input.y:18.8-16: POSIX Yacc forbids dashes in symbol names: with-dash
+AT_BISON_CHECK([--yacc -Wno-error input.y], [], [],
+[[input.y:9.8-16: warning: POSIX Yacc forbids dashes in symbol names: WITH-DASH [-Wyacc]
+input.y:18.8-16: warning: POSIX Yacc forbids dashes in symbol names: with-dash [-Wyacc]
]])
# So warn about them.
AT_BISON_CHECK([-Wyacc input.y], [], [],
-[[input.y:9.8-16: warning: POSIX Yacc forbids dashes in symbol names: WITH-DASH
-input.y:18.8-16: warning: POSIX Yacc forbids dashes in symbol names: with-dash
+[[input.y:9.8-16: warning: POSIX Yacc forbids dashes in symbol names: WITH-DASH [-Wyacc]
+input.y:18.8-16: warning: POSIX Yacc forbids dashes in symbol names: with-dash [-Wyacc]
]])
# Dashes are fine for GNU Bison.
AT_SETUP([Unclosed constructs])
-# Bison's scan-gram.l once forgot to STRING_FINISH some unclosed constructs, so
-# they were prepended to whatever it STRING_GROW'ed next. It also threw them
-# away rather than returning them to the parser. The effect was confusing
-# subsequent error messages.
+# Bison's scan-gram.l once forgot to STRING_FINISH some unclosed
+# constructs, so they were prepended to whatever it STRING_GROW'ed
+# next. It also threw them away rather than returning them to the
+# parser. The effect was confusing subsequent error messages.
AT_DATA([input.y],
[[%token A "a
AT_SETUP([%start after first rule])
-# Bison once complained that a %start after the first rule was a redeclaration
-# of the start symbol.
+# Bison once complained that a %start after the first rule was a
+# redeclaration of the start symbol.
AT_DATA([input.y],
[[%%
]])
AT_BISON_CHECK([[input.y]], [[0]], [],
-[[input.y:2.8-17: warning: token for %prec is not defined: PREC
+[[input.y:2.8-17: warning: token for %prec is not defined: PREC [-Wother]
]])
AT_CLEANUP
# Front-end.
AT_DATA([[input.y]],
-[[%define lr.default-reductions bogus
+[[%define lr.default-reduction bogus
%%
start: ;
]])
AT_BISON_CHECK([[input.y]], [[1]], [[]],
-[[input.y:1.9-29: error: invalid value for %define variable 'lr.default-reductions': 'bogus'
-input.y:1.9-29: accepted value: 'most'
-input.y:1.9-29: accepted value: 'consistent'
-input.y:1.9-29: accepted value: 'accepting'
+[[input.y:1.9-28: error: invalid value for %define variable 'lr.default-reduction': 'bogus'
+input.y:1.9-28: accepted value: 'most'
+input.y:1.9-28: accepted value: 'consistent'
+input.y:1.9-28: accepted value: 'accepting'
]])
# Back-end.
]])
AT_BISON_CHECK([[input.y]], [1], [],
[[input.y:1.9-21: error: invalid value for %define variable 'api.push-pull': 'neither'
-input.y:1.9-21: error: accepted value: 'pull'
-input.y:1.9-21: error: accepted value: 'push'
-input.y:1.9-21: error: accepted value: 'both'
+input.y:1.9-21: accepted value: 'pull'
+input.y:1.9-21: accepted value: 'push'
+input.y:1.9-21: accepted value: 'both'
]])
AT_CLEANUP
start: ;
]])
AT_BISON_CHECK([[input.y]], [1], [],
-[[input.y:1.9-21: error: invalid value for %define variable 'api.push-pull': 'neither'
-input.y:1.9-21: error: accepted value: 'pull'
-input.y:1.9-21: error: accepted value: 'push'
-input.y:1.9-21: error: accepted value: 'both'
+[[input.y:1.9-21: warning: deprecated %define variable name: 'api.push_pull', use 'api.push-pull' [-Wdeprecated]
+input.y:1.9-21: error: invalid value for %define variable 'api.push-pull': 'neither'
+input.y:1.9-21: accepted value: 'pull'
+input.y:1.9-21: accepted value: 'push'
+input.y:1.9-21: accepted value: 'both'
]])
AT_DATA([[input.y]],
start: ;
]])
AT_BISON_CHECK([[input.y]], [1], [],
-[[input.y:1.9-34: error: invalid value for %define Boolean variable 'lr.keep-unreachable-states'
+[[input.y:1.9-34: warning: deprecated %define variable name: 'lr.keep_unreachable_states', use 'lr.keep-unreachable-state' [-Wdeprecated]
+input.y:1.9-34: error: invalid value for %define Boolean variable 'lr.keep-unreachable-state'
+]])
+
+AT_DATA([[input.y]],
+[[%define namespace "foo"
+%define api.namespace "foo"
+%%
+start: ;
+]])
+AT_BISON_CHECK([[input.y]], [1], [],
+[[input.y:1.9-17: warning: deprecated %define variable name: 'namespace', use 'api.namespace' [-Wdeprecated]
+input.y:2.9-21: error: %define variable 'api.namespace' redefined
+input.y:1.9-17: previous definition
]])
AT_DATA([[input.y]],
AT_DATA([[input.y]],
[[%language "C++"
%defines
-%define namespace "]$1["
+%define api.namespace "]$1["
%%
start: ;
]])
AT_BISON_CHECK([[input.y]], [1], [],
[m4_foreach([b4_arg], m4_dquote(m4_shift($@)),
-[[input.y:3.9-17: error: ]b4_arg[
+[[input.y:3.9-21: error: ]b4_arg[
]])])
])
AT_CHECK([[$PERL -e "print 'start: \'';" >> empty.y || exit 77]])
AT_BISON_CHECK([empty.y], [1], [],
-[[empty.y:2.8-9: warning: empty character literal
-empty.y:3.8-4.0: warning: empty character literal
+[[empty.y:2.8-9: warning: empty character literal [-Wother]
+empty.y:3.8-4.0: warning: empty character literal [-Wother]
empty.y:3.8-4.0: error: missing "'" at end of line
-empty.y:4.8: warning: empty character literal
+empty.y:4.8: warning: empty character literal [-Wother]
empty.y:4.8: error: missing "'" at end of file
]])
AT_CHECK([[$PERL -e "print 'start: \'ab';" >> two.y || exit 77]])
AT_BISON_CHECK([two.y], [1], [],
-[[two.y:2.8-11: warning: extra characters in character literal
-two.y:3.8-4.0: warning: extra characters in character literal
+[[two.y:2.8-11: warning: extra characters in character literal [-Wother]
+two.y:3.8-4.0: warning: extra characters in character literal [-Wother]
two.y:3.8-4.0: error: missing "'" at end of line
-two.y:4.8-10: warning: extra characters in character literal
+two.y:4.8-10: warning: extra characters in character literal [-Wother]
two.y:4.8-10: error: missing "'" at end of file
]])
AT_CHECK([[$PERL -e "print 'start: \'abc';" >> three.y || exit 77]])
AT_BISON_CHECK([three.y], [1], [],
-[[three.y:2.8-12: warning: extra characters in character literal
-three.y:3.8-4.0: warning: extra characters in character literal
+[[three.y:2.8-12: warning: extra characters in character literal [-Wother]
+three.y:3.8-4.0: warning: extra characters in character literal [-Wother]
three.y:3.8-4.0: error: missing "'" at end of line
-three.y:4.8-11: warning: extra characters in character literal
+three.y:4.8-11: warning: extra characters in character literal [-Wother]
three.y:4.8-11: error: missing "'" at end of file
]])
AT_BISON_CHECK([input.y], [1], [],
[[input.y:2.9-12: error: invalid number after \-escape: 777
-input.y:2.8-13: warning: empty character literal
+input.y:2.8-13: warning: empty character literal [-Wother]
input.y:2.16-17: error: invalid number after \-escape: 0
-input.y:2.15-18: warning: empty character literal
+input.y:2.15-18: warning: empty character literal [-Wother]
input.y:2.21-25: error: invalid number after \-escape: xfff
-input.y:2.20-26: warning: empty character literal
+input.y:2.20-26: warning: empty character literal [-Wother]
input.y:2.29-31: error: invalid number after \-escape: x0
-input.y:2.28-32: warning: empty character literal
+input.y:2.28-32: warning: empty character literal [-Wother]
input.y:3.9-14: error: invalid number after \-escape: uffff
-input.y:3.8-15: warning: empty character literal
+input.y:3.8-15: warning: empty character literal [-Wother]
input.y:3.18-23: error: invalid number after \-escape: u0000
-input.y:3.17-24: warning: empty character literal
+input.y:3.17-24: warning: empty character literal [-Wother]
input.y:3.27-36: error: invalid number after \-escape: Uffffffff
-input.y:3.26-37: warning: empty character literal
+input.y:3.26-37: warning: empty character literal [-Wother]
input.y:3.40-49: error: invalid number after \-escape: U00000000
-input.y:3.39-50: warning: empty character literal
+input.y:3.39-50: warning: empty character literal [-Wother]
input.y:4.9-10: error: invalid character after \-escape: ' '
-input.y:4.8-11: warning: empty character literal
+input.y:4.8-11: warning: empty character literal [-Wother]
input.y:4.14-15: error: invalid character after \-escape: A
-input.y:4.13-16: warning: empty character literal
+input.y:4.13-16: warning: empty character literal [-Wother]
input.y:5.9-16: error: invalid character after \-escape: \t
input.y:5.17: error: invalid character after \-escape: \f
input.y:5.18: error: invalid character after \-escape: \0
# -Werror is not enabled by -Wall or equivalent.
AT_BISON_CHECK([[-Wall input.y]], [[0]], [[]],
-[[input.y:2.1-7: warning: POSIX Yacc forbids dashes in symbol names: foo-bar
+[[input.y:2.1-7: warning: POSIX Yacc forbids dashes in symbol names: foo-bar [-Wyacc]
]])
AT_BISON_CHECK([[-W input.y]], [[0]], [[]],
-[[input.y:2.1-7: warning: POSIX Yacc forbids dashes in symbol names: foo-bar
+[[input.y:2.1-7: warning: POSIX Yacc forbids dashes in symbol names: foo-bar [-Wyacc]
]])
AT_BISON_CHECK([[-Wno-none input.y]], [[0]], [[]],
-[[input.y:2.1-7: warning: POSIX Yacc forbids dashes in symbol names: foo-bar
+[[input.y:2.1-7: warning: POSIX Yacc forbids dashes in symbol names: foo-bar [-Wyacc]
]])
# -Werror is not disabled by -Wnone or equivalent.
AT_BISON_CHECK([[-Werror,none,yacc input.y]], [[1]], [[]], [[stderr]])
AT_CHECK([[sed 's/^.*bison:/bison:/' stderr]], [[0]],
-[[bison: warnings being treated as errors
-input.y:2.1-7: warning: POSIX Yacc forbids dashes in symbol names: foo-bar
+[[input.y:2.1-7: error: POSIX Yacc forbids dashes in symbol names: foo-bar [-Werror=yacc]
]])
[mv stderr experr]
AT_BISON_CHECK([[-Werror,no-all,yacc input.y]], [[1]], [[]], [[experr]])
# check that the warnings are reported once, not three times.
AT_DATA_GRAMMAR([[input.y]],
-[[%token TOK
+[[%type <TYPE> exp
+%token <TYPE> TOK TOK2
%destructor { $%; @%; } <*> exp TOK;
%initial-action { $%; @%; };
%printer { $%; @%; } <*> exp TOK;
]])
AT_BISON_CHECK([[input.y]], 0, [],
-[[input.y:10.19: warning: stray '$'
-input.y:10.23: warning: stray '@'
-input.y:11.19: warning: stray '$'
-input.y:11.23: warning: stray '@'
-input.y:12.19: warning: stray '$'
-input.y:12.23: warning: stray '@'
-input.y:14.19: warning: stray '$'
-input.y:14.23: warning: stray '@'
+[[input.y:11.19: warning: stray '$' [-Wother]
+input.y:11.23: warning: stray '@' [-Wother]
+input.y:12.19: warning: stray '$' [-Wother]
+input.y:12.23: warning: stray '@' [-Wother]
+input.y:13.19: warning: stray '$' [-Wother]
+input.y:13.23: warning: stray '@' [-Wother]
+input.y:15.19: warning: stray '$' [-Wother]
+input.y:15.23: warning: stray '@' [-Wother]
]])
AT_CLEANUP
[AT_DATA([[input.y]],
[[%type <$1(DEAD %type)> exp
%token <$1(DEAD %token)> a
+%token b
%initial-action
{
$$;
};
%%
exp:
- a a[last]
+ a a[name] b
{
$$;
$][1;
$<$1(DEAD action 1)>$
$<$1(DEAD action 2)>1
- $<$1(DEAD action 3)>last
+ $<$1(DEAD action 3)>name
$<$1(DEAD action 4)>0
;
};
m4_popdef([AT_TEST])
AT_CLEANUP
+
+##----------------------- ##
+## Deprecated directives. ##
+## ---------------------- ##
+
+AT_SETUP([[Deprecated directives]])
+
+AT_KEYWORDS([[deprec]])
+
+AT_DATA_GRAMMAR([[input.y]],
+[[
+%default_prec
+%error_verbose
+%expect_rr 0
+%file-prefix = "foo"
+%file-prefix
+ =
+"bar"
+%fixed-output_files
+%fixed_output-files
+%fixed-output-files
+%name-prefix= "foo"
+%no-default_prec
+%no_default-prec
+%no_lines
+%output = "foo"
+%pure_parser
+%token_table
+%glr-parser
+%% exp : '0'
+]])
+
+AT_BISON_CHECK([[input.y]], [[0]], [[]],
+[[input.y:10.1-13: warning: deprecated directive: '%default_prec', use '%default-prec' [-Wdeprecated]
+input.y:11.1-14: warning: deprecated directive: '%error_verbose', use '%define parse.error verbose' [-Wdeprecated]
+input.y:12.1-10: warning: deprecated directive: '%expect_rr', use '%expect-rr' [-Wdeprecated]
+input.y:13.1-14: warning: deprecated directive: '%file-prefix =', use '%file-prefix' [-Wdeprecated]
+input.y:14.1-15.2: warning: deprecated directive: '%file-prefix\n =', use '%file-prefix' [-Wdeprecated]
+input.y:17.1-19: warning: deprecated directive: '%fixed-output_files', use '%fixed-output-files' [-Wdeprecated]
+input.y:18.1-19: warning: deprecated directive: '%fixed_output-files', use '%fixed-output-files' [-Wdeprecated]
+input.y:20.1-13: warning: deprecated directive: '%name-prefix=', use '%name-prefix' [-Wdeprecated]
+input.y:21.1-16: warning: deprecated directive: '%no-default_prec', use '%no-default-prec' [-Wdeprecated]
+input.y:22.1-16: warning: deprecated directive: '%no_default-prec', use '%no-default-prec' [-Wdeprecated]
+input.y:23.1-9: warning: deprecated directive: '%no_lines', use '%no-lines' [-Wdeprecated]
+input.y:24.1-9: warning: deprecated directive: '%output =', use '%output' [-Wdeprecated]
+input.y:25.1-12: warning: deprecated directive: '%pure_parser', use '%pure-parser' [-Wdeprecated]
+input.y:26.1-12: warning: deprecated directive: '%token_table', use '%token-table' [-Wdeprecated]
+]])
+
+AT_CLEANUP
+
+## ---------------------------- ##
+## Unput's effect on locations. ##
+## ---------------------------- ##
+dnl When the scanner detects a deprecated construct, it unputs the correct
+dnl version, but it should *not* have any impact on the scanner cursor. If it
+dnl does, the locations of directives on the same line become erroneous.
+
+AT_SETUP([[Unput's effect on locations]])
+
+AT_KEYWORDS([[deprec]])
+
+AT_DATA_GRAMMAR([[input.y]],
+[[
+%glr-parser
+%expect_rr 42 %expect_rr 42
+ %expect_rr 42
+%error_verbose %error_verbose
+ %error_verbose
+%% exp: '0'
+]])
+
+AT_BISON_CHECK([[input.y]], [[1]], [[]],
+[[input.y:11.1-10: warning: deprecated directive: '%expect_rr', use '%expect-rr' [-Wdeprecated]
+input.y:11.15-24: warning: deprecated directive: '%expect_rr', use '%expect-rr' [-Wdeprecated]
+input.y:12.15-24: warning: deprecated directive: '%expect_rr', use '%expect-rr' [-Wdeprecated]
+input.y:13.1-14: warning: deprecated directive: '%error_verbose', use '%define parse.error verbose' [-Wdeprecated]
+input.y:13.16-29: warning: deprecated directive: '%error_verbose', use '%define parse.error verbose' [-Wdeprecated]
+input.y:13.11-21: error: %define variable 'parse.error' redefined
+input.y:13-6: previous definition
+input.y:14.16-29: warning: deprecated directive: '%error_verbose', use '%define parse.error verbose' [-Wdeprecated]
+input.y:14.11-21: error: %define variable 'parse.error' redefined
+input.y:13.11-21: previous definition
+]])
+
+AT_CLEANUP
+
+##--------------------------- ##
+## Non-deprecated directives. ##
+## -------------------------- ##
+
+AT_SETUP([[Non-deprecated directives]])
+
+AT_KEYWORDS([[deprec]])
+
+AT_DATA_GRAMMAR([[input.y]],
+[[
+%default-prec
+%error-verbose
+%expect-rr 42
+%file-prefix "foo"
+%file-prefix
+"bar"
+%fixed-output-files
+%name-prefix "foo"
+%no-default-prec
+%no-lines
+%output "foo"
+%pure-parser
+%token-table
+%% exp : '0'
+]])
+
+AT_BISON_CHECK([[input.y]], [[0]], [[]],
+[[input.y: warning: %expect-rr applies only to GLR parsers [-Wother]
+]])
+
+AT_CLEANUP
# --------------------------------------------------
# This macro works around the impossibility to define macros
# inside macros, because issuing `[$1]' is not possible in M4 :(.
-# This sucks hard, GNU M4 should really provide M5 like $$1.
+# This sucks hard, GNU M4 should really provide M5-like $$1.
m4_define([_AT_BISON_OPTION_PUSHDEFS],
[m4_if([$1$2], $[1]$[2], [],
[m4_fatal([$0: Invalid arguments: $@])])dnl
m4_pushdef([AT_PARAM_IF],
[m4_bmatch([$3], [%parse-param], [$1], [$2])])
# Comma-terminated list of formals parse-parameters.
-# E.g., %parse-param { int x } {int y} -> "int x, int y, ".
+# E.g., %parse-param { int x } %parse-param {int y} -> "int x, int y, ".
+# FIXME: Support grouped parse-param.
m4_pushdef([AT_PARSE_PARAMS])
m4_bpatsubst([$3], [%parse-param { *\([^{}]*[^{} ]\) *}],
[m4_append([AT_PARSE_PARAMS], [\1, ])])
[m4_bmatch([$3], [\(%define api\.prefix\|%name-prefix\) ".*"],
[m4_bregexp([$3], [\(%define api\.prefix\|%name-prefix\) "\([^""]*\)"], [\2])],
[yy])])
+m4_pushdef([AT_TOKEN_CTOR_IF],
+[m4_bmatch([$3], [%define api.token.constructor], [$1], [$2])])
+m4_pushdef([AT_TOKEN_PREFIX],
+[m4_bmatch([$3], [%define api.token.prefix ".*"],
+ [m4_bregexp([$3], [%define api.token.prefix "\(.*\)"], [\1])])])
m4_pushdef([AT_API_prefix],
[m4_bmatch([$3], [%define api\.prefix ".*"],
[m4_bregexp([$3], [%define api\.prefix "\([^""]*\)"], [\1])],
[%skeleton "?glr.c"?])),
[$1], [$2])],
[$2])],
- [$2])])
+ [$2])])
# yyerror always sees the locations (when activated) if the parser is impure.
# When the parser is pure, yyerror sees the location if it is received as an
# are using the C++ parsers.
m4_pushdef([AT_PURE_LEX_IF],
[AT_PURE_IF([$1],
- [AT_SKEL_CC_IF([$1], [$2])])])
+ [AT_SKEL_CC_IF([$1], [$2])])])
m4_pushdef([AT_YYSTYPE],
[AT_SKEL_CC_IF([AT_NAME_PREFIX[::parser::semantic_type]],
[m4_pushdef([AT_LOC], [(*llocp)])
m4_pushdef([AT_VAL], [(*lvalp)])
m4_pushdef([AT_YYLEX_FORMALS],
- [AT_YYSTYPE *lvalp[]AT_LOCATION_IF([, AT_YYLTYPE *llocp])])
+ [AT_YYSTYPE *lvalp[]AT_LOCATION_IF([, AT_YYLTYPE *llocp])])
m4_pushdef([AT_YYLEX_ARGS],
- [lvalp[]AT_LOCATION_IF([, llocp])])
+ [lvalp[]AT_LOCATION_IF([, llocp])])
m4_pushdef([AT_USE_LEX_ARGS],
- [(void) lvalp;AT_LOCATION_IF([(void) llocp])])
+ [(void) lvalp;AT_LOCATION_IF([(void) llocp])])
m4_pushdef([AT_YYLEX_PRE_FORMALS],
- [AT_YYLEX_FORMALS, ])
+ [AT_YYLEX_FORMALS, ])
m4_pushdef([AT_YYLEX_PRE_ARGS],
- [AT_YYLEX_ARGS, ])
+ [AT_YYLEX_ARGS, ])
],
[m4_pushdef([AT_LOC], [[(]AT_NAME_PREFIX[lloc)]])
m4_pushdef([AT_VAL], [[(]AT_NAME_PREFIX[lval)]])
[AT_LOC_PUSHDEF([begin.line], [begin.column], [end.line], [end.column])])],
[AT_LOC_PUSHDEF([first_line], [first_column], [last_line], [last_column])])
+
+AT_GLR_IF([AT_KEYWORDS([glr])])
])# _AT_BISON_OPTION_PUSHDEFS
m4_popdef([AT_YYERROR_ARG_LOC_IF])
m4_popdef([AT_API_PREFIX])
m4_popdef([AT_API_prefix])
+m4_popdef([AT_TOKEN_PREFIX])
+m4_popdef([AT_TOKEN_CTOR_IF])
m4_popdef([AT_NAME_PREFIX])
m4_popdef([AT_LOCATION_TYPE_IF])
m4_popdef([AT_LOCATION_IF])
}]],
[c++], [[/* A C++ error reporting function. */
void
-]AT_NAME_PREFIX[::parser::error (const location_type& l, const std::string& m)
-{
- (void) l;
- std::cerr << ]AT_LOCATION_IF([l << ": " << ])[m << std::endl;
+]AT_NAME_PREFIX[::parser::error (]AT_LOCATION_IF([[const location_type& l, ]])[const std::string& m)
+{ std::cerr << ]AT_LOCATION_IF([l << ": " << ])[m << std::endl;
}]],
[java], [AT_LOCATION_IF([[public void yyerror (Calc.Location l, String s)
- {
+{
if (l == null)
System.err.println (s);
else
[m4_null_if([$2], [AT_BISON_CHECK_XML($@)])
AT_BISON_CHECK_NO_XML($@)])
-m4_define([AT_BISON_WERROR_MSG],
- [[bison: warnings being treated as errors]])
-
-
# AT_BISON_CHECK_(BISON_ARGS, [OTHER_AT_CHECK_ARGS])
# --------------------------------------------------
# Low-level macro to run bison once.
# added after the grammar file name, so skip these checks in that
# case.
if test "$POSIXLY_CORRECT_IS_EXPORTED" = false; then
- ]AT_SAVE_SPECIAL_FILES[
+ ]AT_SAVE_SPECIAL_FILES[
# To avoid expanding it repeatedly, store specified stdout.
]AT_DATA([expout], [$3])[
# Build expected stderr up to and including the "warnings being
# treated as errors" message.
- ]AT_DATA([[at-bison-check-warnings]], [$4])[
- at_bison_check_first=`sed -n \
- '/: warning: /{=;q;}' at-bison-check-warnings`
- : ${at_bison_check_first:=1}
- at_bison_check_first_tmp=`sed -n \
- '/conflicts: [0-9].*reduce$/{=;q;}' at-bison-check-warnings`
- : ${at_bison_check_first_tmp:=1}
- if test $at_bison_check_first_tmp -lt $at_bison_check_first; then
- at_bison_check_first=$at_bison_check_first_tmp
- fi
- if test $at_bison_check_first -gt 1; then
- sed -n "1,`expr $at_bison_check_first - 1`"p \
- at-bison-check-warnings > experr
- fi
- echo ']AT_BISON_WERROR_MSG[' >> experr
-
- # Finish building expected stderr and check. Unlike warnings,
- # complaints cause bison to exit early. Thus, with -Werror, bison
- # does not necessarily report all warnings that it does without
- # -Werror, but it at least reports one.
- at_bison_check_last=`sed -n '$=' stderr`
- : ${at_bison_check_last:=1}
- at_bison_check_last=`expr $at_bison_check_last - 1`
- sed -n "$at_bison_check_first,$at_bison_check_last"p \
- at-bison-check-warnings >> experr
- ]AT_CHECK([[sed 's,.*/\(]AT_BISON_WERROR_MSG[\)$,\1,' \
- stderr 1>&2]], [[0]], [[]], [experr])[
+ ]AT_DATA([[experr]], [$4])[
+ $PERL -pi -e 's{(.*): warning: (.*)\[-W(.*)\]$}
+ {$][1: error: $][2\@<:@-Werror=$][3@:>@}' experr
+ ]AT_CHECK([[sed 's,.*/$,,' stderr 1>&2]], [[0]], [[]], [experr])[
# Now check --warnings=error.
cp stderr experr
# Don't combine these Bison invocations since we want to be sure that
# --report=all isn't required to get the full XML file.
AT_BISON_CHECK_([[--report=all --report-file=xml-tests/test.output \
- --graph=xml-tests/test.dot ]]AT_BISON_ARGS,
- [[0]], [ignore], [ignore])
+ --graph=xml-tests/test.dot ]]AT_BISON_ARGS,
+ [[0]], [ignore], [ignore])
AT_BISON_CHECK_([[--xml=xml-tests/test.xml ]]AT_BISON_ARGS,
- [[0]], [ignore], [ignore])
+ [[0]], [ignore], [ignore])
m4_popdef([AT_BISON_ARGS])dnl
[cp xml-tests/test.output expout]
AT_CHECK([[$XSLTPROC \
# otherwise pass "-c"; this is a hack. The default SOURCES is OUTPUT
# with trailing .o removed, and ".c" appended.
m4_define([AT_COMPILE],
- [AT_CHECK([case $POSIXLY_CORRECT_IS_EXPORTED:$C_COMPILER_POSIXLY_CORRECT in
- true:false) echo 'cannot compile properly with POSIXLY_CORRECT' && exit 77;;
- esac])
+ [AT_CHECK([$BISON_C_WORKS], 0, ignore, ignore)
AT_CHECK(m4_join([ ],
[$CC $CFLAGS $CPPFLAGS],
[m4_bmatch([$1], [[.]], [-c], [$LDFLAGS])],
[-o $1],
[m4_default([$2], [m4_bpatsubst([$1], [\.o$]).c])],
[m4_bmatch([$1], [[.]], [], [$LIBS])]),
- 0, [ignore], [ignore])])
+ 0, [ignore], [ignore])])
# AT_COMPILE_CXX(OUTPUT, [SOURCES = OUTPUT.cc])
# ---------------------------------------------
[-o $1],
[m4_default([$2], [m4_bpatsubst([$1], [\.o$]).cc])],
[m4_bmatch([$1], [[.]], [], [$LIBS])]),
- 0, [ignore], [ignore])])
+ 0, [ignore], [ignore])])
# AT_JAVA_COMPILE(SOURCES)
# ------------------------
[java],
[AT_BISON_CHECK([-o $1.java $1.y])
AT_LANG_COMPILE([$1],
- m4_join([ ],
- [$1.java],
- m4_ifval($2, [[$1-$2.java]]),
+ m4_join([ ],
+ [$1.java],
+ m4_ifval($2, [[$1-$2.java]]),
m4_ifval($3, [[$1-$3.java]])))],
[c++],
[AT_BISON_CHECK([-o $1.cc $1.y])
AT_LANG_COMPILE([$1],
- m4_join([ ],
- [$1.cc],
- m4_ifval($2, [[$1-$2.cc]]),
+ m4_join([ ],
+ [$1.cc],
+ m4_ifval($2, [[$1-$2.cc]]),
m4_ifval($3, [[$1-$3.cc]])))],
[c],
[AT_BISON_CHECK([-o $1.c $1.y])
AT_LANG_COMPILE([$1],
- m4_join([ ],
- [$1.c],
- m4_ifval($2, [[$1-$2.c]]),
+ m4_join([ ],
+ [$1.c],
+ m4_ifval($2, [[$1-$2.c]]),
m4_ifval($3, [[$1-$3.c]])))])
])
projects / bison.git / commitdiff
