* origin/maint:
misc: pacify the Tiny C Compiler
cpp: make the check of Flex version portable
misc: require getline
c++: support wide strings for file names
doc: document carets
tests: enhance existing tests with carets
errors: show carets
getargs: add support for --flags/-f
Conflicts:
doc/bison.texi
m4/.gitignore
src/complain.c
src/flex-scanner.h
src/getargs.c
src/getargs.h
src/gram.c
src/main.c
tests/headers.at
* tests/actions.at: Unset value.
* tests/conflicts.at: Rule useless due to conflicts.
* tests/input.at: Missing terminator, unexpected end of file, command line
redefinition of variable.
* tests/named-refs.at: Many errors.
* tests/reduce.at: Useless nonterminals and rules.
* tests/regression.at: Large token.
* origin/maint:
tests: close files in glr-regression
xml: match DOT output and xml2dot.xsl processing
xml: factor xslt space template
graph: fix a memory leak
xml: documentation
output: capitalize State
This improves readability. This is also what gcc does.
* NEWS: Document this change.
* src/complain.c (complain_at): Prefix all errors with "error: ".
(complain_at_indent, warn_at_indent): Do not prefix the context
information of errors, which are basically just indented errors.
* tests/conflicts.at, tests/glr-regression.at, tests/input.at,
tests/named-refs.at, tests/output.at, tests/push.at,
tests/regression.at, tests/skeletons.at: Apply this change.
Signed-off-by: Akim Demaille <akim@lrde.epita.fr>
The current routines used to display s/r and r/r conflicts are both
inconvenient from the programmer point of view (they do not use the
warning infrastructure) and for the user (the messages are rather
terse, not necessarily pleasant to read, and because they don't use
the same routines, they look different).
It was due to the belief (dating back to the initial checked-in
version of Bison) that, at some point, POSIX Yacc mandated the format
for these messages. Today, the Open Group's manual page for Yacc,
<http://pubs.opengroup.org/onlinepubs/009695399/utilities/yacc.html>,
explicitly states that the format of these messages is unspecified.
See commit be7280480c and
<http://lists.gnu.org/archive/html/bison-patches/2002-12/msg00027.html>.
For a discussion on the chosen warning format, see
http://lists.gnu.org/archive/html/bison-patches/2012-09/msg00039.html
In an effort to factor the handling of errors and warnings, use the
Bison warning routines to report these messages.
* src/conflicts.c (conflicts_print): Rewrite with clearer sections
about S/R and then R/R conflicts.
(conflict_report): Remove, inlined in its sole
caller...
(conflicts_output): here.
* tests/conflicts.at, tests/existing.at, tests/glr-regression.at,
* tests/reduce.at, tests/regression.at: Adjust the expected results.
* NEWS: Update.
* src/conflicts.c (conflicts_print): Complain about %expect-rr if not
in GLR mode, regardless of the number of reduce/reduce conflicts.
* tests/conflicts.at (%expect-rr non GLR): New test.
* NEWS: Update.
* origin/maint:
tests: use the generalized default yylex.
tests: AT_YYERROR_DEFINE: prepare for list of ints.
skeletons: no longer define YYLSP_NEEDED.
c++: do not export YYTOKEN_TABLE and YYERROR_VERBOSE.
Conflicts:
data/c.m4
data/glr.cc
data/lalr1.cc
doc/bison.texi
tests/regression.at
* origin/maint:
tests: do not output m4 set up.
tests: use the generic yyerror function.
tests: use assert instead of plain abort.
tests: improve the generic yylex implementation.
tests: generalize the compilation macros.
tests: fix confusion between api.prefix and name-prefix.
maint: gitignores.
yacc: work around the ylwrap limitation.
Conflicts:
NEWS
tests/local.at
* origin/maint:
maint: formatting changes.
tests: support api.prefix.
tests: pacify font-lock-mode.
tests: remove test covered elsewhere.
tests: factor the declaration/definition of yyerror and yylex.
regen.
tests: portability issues.
tests: call the parser from another compilation unit.
glr.c, yacc.c: declare yydebug in the header.
skeletons: use header guards.
tests: improve AT_FULL_COMPILE.
tests: reorder.
tests: strengthen the test on generated headers inclusion
yacc.c: instead of duplicating y.tab.h inside y.tac.c, include it.
yacc.c: factor.
Conflicts:
NEWS
data/glr.c
data/yacc.c
src/parse-gram.c
src/parse-gram.h
tests/conflicts.at
tests/regression.at
* cfg.mk: Skip bison generated files, 2.5 is generating trailing
blanks. This is already fixed in master.
* tests/conflicts.at, tests/java.at: Fix white space issues.
Thus, conflict reports are now affected by -Werror and -Wnone
(unless %expect or %expect-rr is specified). Reported by George
Neuner at
<http://lists.gnu.org/archive/html/bug-bison/2010-08/msg00002.html>.
* NEWS (2.5): Document.
* doc/bison.texinfo (Bison Options): Document.
* src/complain.c, src/complain.h (set_warning_issued): Export
function.
* src/conflicts.c (conflicts_print): Suppress conflict report
based on -Wno-conflicts-sr and -Wno-conflicts-rr, and treat
conflicts as errors if -Werror.
* src/getargs.c (warnings_flag): Initialize with
warnings_conflicts_sr and warnings_conflicts_rr as well.
(warnings_args, warnings_types): Add entries for
warnings_conflicts_sr and warnings_conflicts_rr.
(usage): Update.
* src/getargs.h (enum warnings): Add entries for
warnings_conflicts_sr and warnings_conflicts_rr.
* tests/conflicts.at (-W versus %expect and %expect-rr): New test
group.
* tests/local.at (AT_BISON_CHECK_NO_XML): Update now that the
conflict report can produce a "warnings being treated as errors"
message. Also, check that stderr is now fully scrubbed by -Wnone
when the exit status is 0.
(cherry picked from commit 6f8bdce25d)
Thus, conflict reports are now affected by -Werror and -Wnone
(unless %expect or %expect-rr is specified). Reported by George
Neuner at
<http://lists.gnu.org/archive/html/bug-bison/2010-08/msg00002.html>.
* NEWS (2.5): Document.
* doc/bison.texinfo (Bison Options): Document.
* src/complain.c, src/complain.h (set_warning_issued): Export
function.
* src/conflicts.c (conflicts_print): Suppress conflict report
based on -Wno-conflicts-sr and -Wno-conflicts-rr, and treat
conflicts as errors if -Werror.
* src/getargs.c (warnings_flag): Initialize with
warnings_conflicts_sr and warnings_conflicts_rr as well.
(warnings_args, warnings_types): Add entries for
warnings_conflicts_sr and warnings_conflicts_rr.
(usage): Update.
* src/getargs.h (enum warnings): Add entries for
warnings_conflicts_sr and warnings_conflicts_rr.
* tests/conflicts.at (-W versus %expect and %expect-rr): New test
group.
* tests/local.at (AT_BISON_CHECK_NO_XML): Update now that the
conflict report can produce a "warnings being treated as errors"
message. Also, check that stderr is now fully scrubbed by -Wnone
when the exit status is 0.
LAC = lookahead correction. See discussion at
<http://lists.gnu.org/archive/html/bison-patches/2009-09/msg00034.html>.
However, one point there must be corrected: because of %nonassoc,
LAC is *not* always redundant for lr.type=canonical-lr.
* data/yacc.c: Accept values of "none" (default) or "full" for
parse.lac. Accept %define parse.lac.es-capacity to specify
capacity of LAC's temporary exploratory stack. It defaults to 20
and, for now, will not grow dynamically.
(b4_lac_flag, b4_lac_if): New m4 macros. Evaluate as true for
parse.lac!=none.
(YYBACKUP): Invoke YY_LAC_DISCARD.
(YY_LAC_ESTABLISH, YY_LAC_DISCARD): New cpp macros that invoke
yy_lac and track when it needs to be invoked
(yy_lac): New function that, given the current stack, determines
whether a token can eventually be shifted. Return status mimics
yyparse return status.
(yysyntax_error): Change yystate argument to yyssp so stack top
can be passed to yy_lac. If LAC is requested, build expected
token list by invoking yy_lac for every token instead of just
checking the current state for lookaheads. Return 2 if yy_lac
exhausts memory.
(yyparse, yypush_parse): Use local variable yy_lac_established and
cpp macros YY_LAC_ESTABLISH and YY_LAC_DISCARD to implement LAC.
Update yysyntax_error invocation. Add yyexhaustedlab code if LAC
is requested.
* tests/conflicts.at (%nonassoc and eof): Extend to check the
effect of each of -Dlr.type=canonical-lr and -Dparse.lac=full.
(%error-verbose and consistent errors): Likewise.
(LAC: %nonassoc requires splitting canonical LR states): New test
group demonstrating how LAC can fix canonical LR.
* tests/input.at (LAC: Errors for %define): New test group.
* tests/regression.at (LAC: Exploratory stack): New test group.
(LAC: Memory exhaustion): New test group.
(cherry picked from commit bf35c71c58)
Conflicts:
src/parse-gram.c
src/parse-gram.h
LAC = lookahead correction. See discussion at
<http://lists.gnu.org/archive/html/bison-patches/2009-09/msg00034.html>.
However, one point there must be corrected: because of %nonassoc,
LAC is *not* always redundant for lr.type=canonical-lr.
* data/yacc.c: Accept values of "none" (default) or "full" for
parse.lac. Accept %define parse.lac.es-capacity to specify
capacity of LAC's temporary exploratory stack. It defaults to 20
and, for now, will not grow dynamically.
(b4_lac_flag, b4_lac_if): New m4 macros. Evaluate as true for
parse.lac!=none.
(YYBACKUP): Invoke YY_LAC_DISCARD.
(YY_LAC_ESTABLISH, YY_LAC_DISCARD): New cpp macros that invoke
yy_lac and track when it needs to be invoked
(yy_lac): New function that, given the current stack, determines
whether a token can eventually be shifted. Return status mimics
yyparse return status.
(yysyntax_error): Change yystate argument to yyssp so stack top
can be passed to yy_lac. If LAC is requested, build expected
token list by invoking yy_lac for every token instead of just
checking the current state for lookaheads. Return 2 if yy_lac
exhausts memory.
(yyparse, yypush_parse): Use local variable yy_lac_established and
cpp macros YY_LAC_ESTABLISH and YY_LAC_DISCARD to implement LAC.
Update yysyntax_error invocation. Add yyexhaustedlab code if LAC
is requested.
* tests/conflicts.at (%nonassoc and eof): Extend to check the
effect of each of -Dlr.type=canonical-lr and -Dparse.lac=full.
(parse.error=verbose and consistent errors): Likewise.
(LAC: %nonassoc requires splitting canonical LR states): New test
group demonstrating how LAC can fix canonical LR.
* tests/input.at (LAC: Errors for %define): New test group.
* tests/regression.at (LAC: Exploratory stack): New test group.
(LAC: Memory exhaustion): New test group.
On master, there is no yychar in lalr1.cc, but there is on
branch-2.5, and the prior cherry-pick of "Fix handling of yychar
manipulation in user semantic actions" wasn't adjusted for that
difference.
* data/lalr1.cc (yy::parser::parse): Translate yychar before
every use of yytoken, and add comments explaining this approach.
* tests/conflicts.at (%error-verbose and consistent errors):
Extend to test yychar manipulation with lalr1.cc.
* NEWS (2.5): Document.
* data/yacc.c (yysyntax_error): In a verbose syntax error
message while in a consistent state with a default action (which
must be an error action given that yysyntax_error is being
invoked), continue to drop the expected token list, but don't
drop the unexpected token unless there actually is no lookahead.
Moreover, handle that internally instead of returning 1 to tell
the caller to do it. With that meaning of 1 gone, renumber
return codes more usefully.
(yyparse, yypush_parse): Update yysyntax_error usage. Most
importantly, set yytoken to YYEMPTY when there's no lookahead.
* data/glr.c (yyreportSyntaxError): As in yacc.c, don't drop the
unexpected token unless there actually is no lookahead.
* data/lalr1.cc (yy::parser::parse): If there's no lookahead,
set yytoken to yyempty_ before invoking yysyntax_error_.
(yy::parser::yysyntax_error_): Again, don't drop the unexpected
token unless there actually is no lookahead.
* data/lalr1.java (YYParser::parse): If there's no lookahead,
set yytoken to yyempty_ before invoking yysyntax_error.
(YYParser::yysyntax_error): Again, don't drop the unexpected
token unless there actually is no lookahead.
* tests/conflicts.at (%error-verbose and consistent
errors): Extend test group to further reveal how the previous
use of the simple "syntax error" message was too general. Test
yacc.c, glr.c, lalr1.cc, and lalr1.java. No longer an expected
failure.
* tests/java.at (AT_JAVA_COMPILE, AT_JAVA_PARSER_CHECK): Move
to...
* tests/local.at: ... here.
(_AT_BISON_OPTION_PUSHDEFS): Push AT_SKEL_JAVA_IF definition.
(AT_BISON_OPTION_POPDEFS): Pop it.
(AT_FULL_COMPILE): Extend to handle Java.
(cherry picked from commit d2060f0634)
Conflicts:
data/lalr1.cc
data/lalr1.java
src/parse-gram.c
src/parse-gram.h
tests/java.at
* NEWS (2.5): Document.
* data/yacc.c (yysyntax_error): In a verbose syntax error
message while in a consistent state with a default action (which
must be an error action given that yysyntax_error is being
invoked), continue to drop the expected token list, but don't
drop the unexpected token unless there actually is no lookahead.
Moreover, handle that internally instead of returning 1 to tell
the caller to do it. With that meaning of 1 gone, renumber
return codes more usefully.
(yyparse, yypush_parse): Update yysyntax_error usage. Most
importantly, set yytoken to YYEMPTY when there's no lookahead.
* data/glr.c (yyreportSyntaxError): As in yacc.c, don't drop the
unexpected token unless there actually is no lookahead.
* data/lalr1.cc (yy::parser::parse): If there's no lookahead,
pass yyempty_ not yyla.type to yysyntax_error_.
(yy::parser::yysyntax_error_): Again, don't drop the unexpected
token unless there actually is no lookahead.
* data/lalr1.java (YYParser::parse): If there's no lookahead,
set yytoken to yyempty_ before invoking yysyntax_error.
(YYParser::yysyntax_error): Again, don't drop the unexpected
token unless there actually is no lookahead.
* tests/conflicts.at (parse.error=verbose and consistent
errors): Extend test group to further reveal how the previous
use of the simple "syntax error" message was too general. Test
yacc.c, glr.c, lalr1.cc, and lalr1.java. No longer an expected
failure.
* tests/java.at (AT_JAVA_COMPILE, AT_JAVA_PARSER_CHECK): Move
to...
* tests/local.at: ... here.
(_AT_BISON_OPTION_PUSHDEFS): Push AT_SKEL_JAVA_IF definition.
(AT_BISON_OPTION_POPDEFS): Pop it.
(AT_FULL_COMPILE): Extend to handle Java.
The problem was that yacc.c didn't always update the yychar
translation afterwards. However, other skeletons appear to be
fine. glr.c appears to already translate yychar before every
use. lalr1.cc does not define yychar and does not document its
replacement, yyla, for users. It does provide yyclearin, but
that does not manipulate yyla and thus requires no translation
update. In lalr1.java, yychar is out of scope during semantic
actions.
* NEWS (2.5): Document.
* data/yacc.c (YYBACKUP): Don't bother translating yychar into
yytoken here.
(yyparse, yypush_parse): Instead, translate before every use of
yytoken, and add comments explaining this approach.
* tests/actions.at (Destroying lookahead assigned by semantic
action): New test group checking that translation happens before
lookahead destructor calls at parser return. Previously,
incorrect destructors were called.
* tests/conflicts.at (%error-verbose and consistent
errors): New test group checking that translation happens at
syntax error detection before the associated verbose error
message and the associated lookahead destructor calls. While
the destructor call is fixed by this patch, the verbose error
message is currently incorrect due to another bug (see
comments in test group), so this is an expected failure for now.
(cherry picked from commit df222dfaf4)
Conflicts:
src/parse-gram.c
src/parse-gram.h
The problem was that yacc.c didn't always update the yychar
translation afterwards. However, other skeletons appear to be
fine. glr.c appears to already translate yychar before every
use. lalr1.cc does not define yychar and does not document its
replacement, yyla, for users. It does provide yyclearin, but
that does not manipulate yyla and thus requires no translation
update. In lalr1.java, yychar is out of scope during semantic
actions.
* NEWS (2.5): Document.
* data/yacc.c (YYBACKUP): Don't bother translating yychar into
yytoken here.
(yyparse, yypush_parse): Instead, translate before every use of
yytoken, and add comments explaining this approach.
* tests/actions.at (Destroying lookahead assigned by semantic
action): New test group checking that translation happens before
lookahead destructor calls at parser return. Previously,
incorrect destructors were called.
* tests/conflicts.at (parse.error=verbose and consistent
errors): New test group checking that translation happens at
syntax error detection before the associated verbose error
message and the associated lookahead destructor calls. While
the destructor call is fixed by this patch, the verbose error
message is currently incorrect due to another bug (see
comments in test group), so this is an expected failure for now.
* tests/conflicts.at (%nonassoc and eof): Extend to test that it
prevents the omission of expected tokens for %error-verbose.
(cherry picked from commit d1cc31c5f0)
For now, just api.push-pull and lr.keep-unreachable-states.
Maintain old names for backward compatibility.
* NEWS (2.5): Document.
* data/c.m4 (b4_identification): Update comment.
* data/yacc.c: Update access.
* doc/bison.texinfo: Update.
* etc/bench.pl.in (bench_push_parser): Update use.
* src/files.c (tr): Move to...
* src/getargs.c, src/getargs.h (tr): ... here because I can't
think of a better place to expose it. My logic is that, for all
uses of tr so far, command-line arguments can be involved, and
getargs.h is already included.
* src/main.c (main): Update access.
* src/muscle_tab.c (muscle_percent_define_insert): Convert old
variable names to new variable names before assigning value.
* src/reader.c (reader): Update setting default.
* tests/calc.at: Update uses.
* tests/conflicts.at (Unreachable States After Conflict
Resolution): Update use.
* tests/input.at (%define enum variables): Update use.
(%define backward compatibility): New test group.
* tests/push.at: Update uses.
* tests/reduce.at: Update uses.
* tests/torture.at: Update uses.
(cherry picked from commit 812775a039)
Conflicts:
data/c.m4
etc/bench.pl.in
src/parse-gram.c
src/parse-gram.h
tests/conflicts.at
For now, just api.push-pull and lr.keep-unreachable-states.
Maintain old names for backward compatibility.
* NEWS (2.5): Document.
* data/c.m4 (b4_identification): Update comment.
* data/yacc.c: Update access.
* doc/bison.texinfo: Update.
* etc/bench.pl.in (bench_grammar): Update use.
* src/files.c (tr): Move to...
* src/getargs.c, src/getargs.h (tr): ... here because I can't
think of a better place to expose it. My logic is that, for all
uses of tr so far, command-line arguments can be involved, and
getargs.h is already included.
* src/main.c (main): Update access.
* src/muscle_tab.c (muscle_percent_define_insert): Convert old
variable names to new variable names before assigning value.
* src/reader.c (reader): Update setting default.
* tests/calc.at: Update uses.
* tests/conflicts.at (Unreachable States After Conflict
Resolution): Update use.
* tests/input.at (%define enum variables): Update use.
(%define backward compatibility): New test group.
* tests/push.at: Update uses.
* tests/reduce.at: Update uses.
* tests/torture.at: Update uses.
Unfortunately it is not possible to reuse the %prec directive. This
is because to please POSIX, we do not require to end the rules with a
semicolon. As a result,
foo: bar %prec baz
is ambiguous: either a rule which precedence is that of baz, or a rule,
and then a declaration of the precedence of the token baz.
* doc/bison.texinfo: Document %precedence.
(Precedence Only): New.
* src/assoc.h, src/assoc.c (precedence_assoc): New.
* src/conflicts.c (resolve_sr_conflict): Support it.
* src/scan-gram.l, src/parse-gram.y (%precedence): New token.
Parse it.
* tests/calc.at: Use %precedence for NEG.
* tests/conflicts.at (%precedence does not suffice)
(%precedence suffices): New tests.
starting at
<http://lists.gnu.org/archive/html/bison-patches/2007-11/msg00021.html>.
* configure.ac (XSLTPROC): New substitution.
* Makefile.am (maintainer-xml-check): New phony target invoking...
* tests/Makefile.am (maintainer-xml-check): ... this new phony target
invoking make maintainer-check with BISON_TEST_XML=1.
* tests/atlocal.in (XSLTPROC): New.
* tests/local.at (AT_BISON_CHECK): New macro to (1) instruct Valgrind
not to report reachable memory when Bison is expected to have a
non-zero exit status and (2) to compare XML/XSLT output with --graph
and --report=all output for every working grammar when
BISON_TEST_XML=1.
(AT_BISON_CHECK_NO_XML): Likewise, but skip XML checks.
(AT_BISON_CHECK_XML): New.
(AT_QUELL_VALGRIND): New.
* tests/testsuite.at (ORIGINAL_AT_CHECK): Remove this and...
(AT_CHECK): ... don't redefine this since this was the old way to
quell Valgrind.
* tests/actions.at: Rewrite all AT_CHECK invocations for bison as
AT_BISON_CHECK invocations.
* tests/c++.at: Likewise.
* tests/calc.at: Likewise.
* tests/conflicts.at: Likewise.
* tests/cxx-type.at: Likewise.
* tests/existing.at: Likewise.
* tests/glr-regression.at: Likewise.
* tests/headers.at: Likewise.
* tests/input.at: Likewise.
* tests/java.at: Likewise.
* tests/output.at: Likewise.
* tests/push.at: Likewise.
* tests/reduce.at: Likewise.
* tests/regression.at: Likewise.
* tests/sets.at: Likewise.
* tests/skeletons.at: Likewise.
* tests/synclines.at: Likewise.
* tests/torture.at: Likewise.
(Big triangle): Use AT_BISON_CHECK_NO_XML instead since this grammar
tends to hang xsltproc.
(Big horizontal): Likewise.
When reporting useless rules and nonterminals, say "useless in grammar"
instead of "useless", and say "useless in parser" instead of "never
reduced". Discussed starting at
<http://lists.gnu.org/archive/html/bison-patches/2007-10/msg00033.html>.
* NEWS (2.3a+): Mention this change.
* data/xslt/xml2text.xsl: Update output text and expected input XML
element names to match changes below.
* data/xslt/xml2xhtml.xsl: Likewise.
(xsl:template match="bison-xml-report"): Add missing entry in Table of
Contents: "Rules useless in parser due to conflicts".
* doc/bison.texinfo (Decl Summary): Reword a little.
(Understanding): Update example output for changes below.
* src/gram.c: (rule_useful_p): Rename to...
(rule_useful_in_grammar_p): ... this.
(rule_useless_p): Rename to...
(rule_useless_in_grammar_p): ... this.
(rule_never_reduced_p): Rename to...
(rule_useless_in_parser_p): ... this.
(grammar_rules_print): Update for renames.
(grammar_rules_print_xml): Update for renames.
(grammar_rules_never_reduced_report): Rename to...
(grammar_rules_useless_report): ... this since it is used for either
kind of useless rule.
* src/gram.h: Reword comments and update function names in prototypes.
* src/main.c (main): Say "rule useless in parser due to conflicts".
* src/print-xml.c (print_rules_never_reduced): Rename to...
(print_rules_useless_in_parser): ... this, and rename output XML
element "rules-never-reduced" to "rules-useless-in-parser".
(print_xml): Update for rename.
* src/print.c (print_results): Say "Rules useless in parser due to
conflicts".
* src/reduce.c (reduce_grammar_tables): Say "rule useless in grammar".
(nonterminals_reduce): Say "nonterminal useless in grammar".
(reduce_output): Say "Nonterminals useless in grammar".
Say "Rules useless in grammar".
(reduce_xml): Rename output XML element "useless" to
"useless-in-grammar".
(reduce_print): Don't report the count of grammatically useless rules
as "rules never reduced" just because %yacc is specified.
In the correct report of this count, say nonterminal(s) and rule(s)
"useless in grammar".
* tests/conflicts.at (S/R in initial): Update expected output.
(Defaulted Conflicted Reduction): Likewise.
(Unreachable States After Conflict Resolution): Likewise.
* tests/existing.at (GNU pic Grammar): Likewise.
* tests/reduce.at (Useless Nonterminals): Likewise.
(Useless Rules): Likewise.
(Reduced Automaton): Likewise.
(Underivable Rules): Likewise.
(Empty Language): Likewise.
* NEWS (2.3a+): Mention it in the entry for unreachable state removal.
* doc/bison.texinfo (Decl Summary): Mention it in the %define entry.
* src/main.c (main): Implement it.
* tests/conflicts.at (Unreachable States After Conflict Resolution):
Extend to test it, and fix a typo.
