The introduction of this feature, in 2.4, was four years ago. The --language
option and the %language directive are no longer experimental.
-** New format for error reports: carets
+** 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.
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$$ \
prohibit_strcmp=^doc/bison\.texi$$ \
# 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])
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=$CXXFLAGS
gl_WARN_ADD([-Werror=unknown-warning-option], [CXXFLAGS])
fi
BISON_TEST_FOR_WORKING_C_COMPILER
-BISON_TEST_FOR_WORKING_CXX_COMPILER
BISON_C_COMPILER_POSIXLY_CORRECT
+BISON_TEST_FOR_WORKING_CXX_COMPILER
+BISON_CXX_COMPILER_POSIXLY_CORRECT
AC_ARG_ENABLE([yacc],
[AC_HELP_STRING([--disable-yacc],
This says when, why and how to use the exceptional
action in the middle of a rule.
+Actions in Mid-Rule
+
+* Using Mid-Rule Actions:: Putting an action in the middle of a rule.
+* Mid-Rule Action Translation:: How mid-rule actions are actually processed.
+* Mid-Rule Conflicts:: Mid-rule actions can cause conflicts.
+
Tracking Locations
* Location Type:: Specifying a data type for locations.
@node Grammar Outline
@section Outline of a Bison Grammar
+@cindex comment
+@findex // @dots{}
+@findex /* @dots{} */
A Bison grammar file has four main sections, shown here with the
appropriate delimiters:
@end example
Comments enclosed in @samp{/* @dots{} */} may appear in any of the sections.
-As a GNU extension, @samp{//} introduces a comment that
-continues until end of line.
+As a GNU extension, @samp{//} introduces a comment that continues until end
+of line.
@menu
* Prologue:: Syntax and usage of the prologue.
These actions are written just like usual end-of-rule actions, but they
are executed before the parser even recognizes the following components.
+@menu
+* Using Mid-Rule Actions:: Putting an action in the middle of a rule.
+* Mid-Rule Action Translation:: How mid-rule actions are actually processed.
+* Mid-Rule Conflicts:: Mid-rule actions can cause conflicts.
+@end menu
+
+@node Using Mid-Rule Actions
+@subsubsection Using Mid-Rule Actions
+
A mid-rule action may refer to the components preceding it using
@code{$@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 = $1; @};
+ ^^^^^^^^^^^^^
+@end group
+@end example
+
+
+@node Mid-Rule Conflicts
+@subsubsection Conflicts due to Mid-Rule Actions
Taking action before a rule is completely recognized often leads to
conflicts since the parser must commit to a parse in order to execute the
action. For example, the following two rules, without mid-rule actions,
Now Bison can execute the action in the rule for @code{subroutine} without
deciding which rule for @code{compound} it will eventually use.
+
@node Tracking Locations
@section Tracking Locations
@cindex location
@code{yyerror} are:
@example
-void yyerror (char const *msg); /* Yacc parsers. */
-void yyerror (YYLTYPE *locp, char const *msg); /* GLR parsers. */
+void yyerror (char const *msg); // Yacc parsers.
+void yyerror (YYLTYPE *locp, char const *msg); // GLR parsers.
@end example
But if @samp{%locations %define api.pure %parse-param @{int *nastiness@}} is
@end deffn
@deffn {Value} @@$
-@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:
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
@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
@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
@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
feature.
@end deffn
-@deffn {Construct} /*@dots{}*/
-Comment delimiters, as in C.
+@deffn {Construct} /* @dots{} */
+@deffnx {Construct} // @dots{}
+Comments, as in C/C++.
@end deffn
@deffn {Delimiter} :
@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
--- /dev/null
+// Generated by GNU Bison 2.6.90.
+// Report bugs to <bug-bison@gnu.org>.
+// Home page: <http://www.gnu.org/software/bison/>.
+
+digraph "/tmp/fo.y"
+{
+ node [fontname = courier, shape = box, colorscheme = paired6]
+ edge [fontname = courier]
+
+ 0 [label="State 0\n\l 0 $accept: . exp $end\l 1 exp: . a \";\"\l 2 | . b \".\"\l 3 a: . \"0\"\l 4 b: . \"0\"\l"]
+ 0 -> 1 [style=solid label="\"0\""]
+ 0 -> 2 [style=dashed label="exp"]
+ 0 -> 3 [style=dashed label="a"]
+ 0 -> 4 [style=dashed label="b"]
+ 1 [label="State 1\n\l 3 a: \"0\" . [\";\"]\l 4 b: \"0\" . [\".\"]\l"]
+ 1 -> "1R3" [style=solid]
+ "1R3" [label="R3", fillcolor=3, shape=diamond, style=filled]
+ 1 -> "1R4" [label="[\".\"]", style=solid]
+ "1R4" [label="R4", fillcolor=3, shape=diamond, style=filled]
+ 2 [label="State 2\n\l 0 $accept: exp . $end\l"]
+ 2 -> 5 [style=solid label="$end"]
+ 3 [label="State 3\n\l 1 exp: a . \";\"\l"]
+ 3 -> 6 [style=solid label="\";\""]
+ 4 [label="State 4\n\l 2 exp: b . \".\"\l"]
+ 4 -> 7 [style=solid label="\".\""]
+ 5 [label="State 5\n\l 0 $accept: exp $end .\l"]
+ 5 -> "5R0" [style=solid]
+ "5R0" [label="Acc", fillcolor=1, shape=diamond, style=filled]
+ 6 [label="State 6\n\l 1 exp: a \";\" .\l"]
+ 6 -> "6R1" [style=solid]
+ "6R1" [label="R1", fillcolor=3, shape=diamond, style=filled]
+ 7 [label="State 7\n\l 2 exp: b \".\" .\l"]
+ 7 -> "7R2" [style=solid]
+ "7R2" [label="R2", fillcolor=3, shape=diamond, style=filled]
+}
--- /dev/null
+%%
+exp: a ";" | b ".";
+a: "0";
+b: "0";
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])
])
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);
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);
}
}
{
warnings warn_flag = midrule_warning ? Wmidrule_values : Wother;
if (n)
- complain (&r->location, warn_flag, _("unused value: $%d"), n);
+ complain (&l->location, warn_flag, _("unused value: $%d"), n);
else
- complain (&r->location, warn_flag, _("unset value: $$"));
+ complain (&l->location, warn_flag, _("unset value: $$"));
}
}
}
[[input.y:24.70-72: warning: useless %destructor for type <*> [-Wother]
input.y:24.70-72: warning: useless %printer for type <*> [-Wother]
input.y:33.3-23: warning: unset value: $$ [-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: $$ [-Wother]
{ @$ = 4; } // Only used.
^^^^^^^^^^^^^^^^^^^^^
-input.y:30.3-35.37: warning: unused value: $3 [-Wother]
- { @$ = 1; } // Not set or used.
- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+input.y:32.3-23: warning: unused value: $3 [-Wother]
+ { USE ($$); @$ = 3; } // Only set.
+ ^^^^^^^^^^^^^^^^^^^^^
]])
AT_COMPILE([input])
# 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. ##
## ------------------- ##
# 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
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_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_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_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_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_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])
## ------------------------------------------------------------------------- ##
-## Duplicated user destructor for lookahead. See ##
+## Duplicated user destructor for lookahead. See ##
## <http://lists.gnu.org/archive/html/bison-patches/2005-08/msg00035.html>. ##
## ------------------------------------------------------------------------- ##
## ------------------------------------------------------------------------- ##
-## 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_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_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_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_CLEANUP
-## ------------------------------------------------------------------------- ##
-## Incorrect lookahead during nondeterministic GLR. ##
-## ------------------------------------------------------------------------- ##
+## ------------------------------------------------- ##
+## Incorrect lookahead during nondeterministic GLR. ##
+## ------------------------------------------------- ##
AT_SETUP([Incorrect lookahead during nondeterministic GLR])
AT_CLEANUP
-## ------------------------------------------------------------------------- ##
-## Leaked semantic values when reporting ambiguity. ##
-## ------------------------------------------------------------------------- ##
+## ------------------------------------------------- ##
+## Leaked semantic values when reporting ambiguity. ##
+## ------------------------------------------------- ##
AT_SETUP([Leaked semantic values when reporting ambiguity])
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_CLEANUP
-## ------------------------------------------------------------------------- ##
-## Uninitialized location when reporting ambiguity. ##
-## ------------------------------------------------------------------------- ##
+## ------------------------------------------------- ##
+## Uninitialized location when reporting ambiguity. ##
+## ------------------------------------------------- ##
AT_SETUP([Uninitialized location when reporting ambiguity])
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_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: $][$ [-Wother]
+ a: INT | INT { } INT { } INT { };
+ ^^^^^^^^^^^^^^^^^^^^^^^
+input.y:11.10-12: warning: unused value: $][1 [-Wother]
+ a: INT | INT { } INT { } INT { };
+ ^^^
+input.y:11.18-20: warning: unused value: $][3 [-Wother]
+ a: INT | INT { } INT { } INT { };
+ ^^^
+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 [-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: $][$ [-Wmidrule-values]
+ c: INT | INT { $][1; } INT { $<integer>2; } INT { $<integer>4; };
+ ^^^^^^^
+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: $][$ [-Wother]
+ c: INT | INT { $][1; } INT { $<integer>2; } INT { $<integer>4; };
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+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 [-Wother]
+ c: INT | INT { $][1; } INT { $<integer>2; } INT { $<integer>4; };
+ ^^^
+]]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: $][$ [-Wother]
+ d: INT | INT { } INT { $][1; } INT { $<integer>2; };
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+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 [-Wother]
+ d: INT | INT { } INT { $][1; } INT { $<integer>2; };
+ ^^^
+input.y:15.10-37: warning: unset value: $][$ [-Wother]
+ e: INT | INT { } INT { } INT { $][1; };
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+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 [-Wother]
+ e: INT | INT { } INT { } INT { $][1; };
+ ^^^
+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 [-Wother]
+ g: INT | INT { $<integer>$; } INT { $<integer>$; } INT { };
+ ^^^
+]]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 [-Wother]
+ g: INT | INT { $<integer>$; } INT { $<integer>$; } INT { };
+ ^^^
+]]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 [-Wother]
+ g: INT | INT { $<integer>$; } INT { $<integer>$; } INT { };
+ ^^^
+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 [-Wother]
+ h: INT | INT { $<integer>$; } INT { $<integer>$ = $<integer>2; } INT { };
+ ^^^
+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 [-Wmidrule-values]
+ h: INT | INT { $<integer>$; } INT { $<integer>$ = $<integer>2; } INT { };
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+]]])[[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 [-Wmidrule-values]
+ j: INT | INT INT { $<integer>$ = 1; } { $][$ = $][1 + $][2; };
+ ^^^^^^^^^^^^^^^^^^^^
+]]])[[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 [-Wother]
+ k: INT | INT INT { $<integer>$; } { $<integer>$ = $<integer>3; } { };
+ ^^^
+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 [-Wmidrule-values]
+ k: INT | INT INT { $<integer>$; } { $<integer>$ = $<integer>3; } { };
+ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+]]]))
+])
## --------------- ##
## Unused values. ##
AT_BISON_CHECK([input.y], [0], [],
[[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: $$ [-Wother]
]])
]])
AT_BISON_CHECK([input.y], [0], [],
-[[input.y:6.8-45: warning: unused value: $4 [-Wother]
+[[input.y:6.23-28: warning: unused value: $4 [-Wother]
input.y:8.9-11: warning: unset value: $$ [-Wother]
]])
AT_BISON_CHECK([input.y], [0], [],
[[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]
]])
# 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])],
# #error "1"
# ^
#
-# And possibly distcc adds its bits.
+# Possibly distcc adds its bits.
#
# distcc[33187] ERROR: compile (null) on localhost failed
# syncline.c:1:2: error: #error "1"
# #error "1"
# ^
# 1 error generated.
+#
+# When c++ is used to compiler C, we might have more messages (Clang 3.2):
+#
+# clang: warning: treating 'c' input as 'c++' when in C++ mode, this behavior is deprecated
+
AT_CHECK([[$PERL -p -0777 - stderr <<\EOF
# 1. Remove useless lines.
# distcc clutter.
s/^distcc\[\d+\] .*\n//gm;
+ # c vs. c++.
+ s/^clang: warning: treating 'c' input as 'c\+\+'.*\n//gm;
# Function context.
s/^[^:]*: In function '[^']+':\n//gm;
# Caret error.
projects / bison.git / commitdiff
