https://lists.gnu.org/archive/html/bison-patches/2019-08/msg00007.html
When Bison is started with a flag that suppresses warning messages, the
error_message() function can produce a few gigabytes of indentation
because of a dangling pointer.
* src/complain.c (error_message): Don't reset indent_ptr here, but...
(complain_indent): here.
* tests/diagnostics.at (Indentation with message suppression): Check
this case.
* tests/regression.at: Use %expect to avoid warnings.
Set the keywords to facilitate running specific tests.
Use macros such as AT_YYLEX_DECLARE to facilitate tests for other
languages.
Likewise for AT_FULL_COMPILE.
See the previous commit. This option should be removed, -o suffices.
* src/getargs.c (FIXED_OUTPUT_FILES): New.
Add support for it.
(getargs): Define loc, and use it.
This is safer when we need to pass a pointer to a location.
The name fixed-output-files is pretty clear: generate y.tab.c, as Yacc
does. So let's detach this from %yacc which does more: it requires
POSIX Yacc behavior.
This directive is obsolete since December 29th 2001
8c9a50bee1. It does not show in the
doc. I don't want to spend more time on improving its diagnostics, it
could be removed just as well as far as I'm concerned.
* src/scan-gram.l, src/parse-gram.y (%fixed-output-files): Detach from
%yacc.
* configure.ac (DCFLAGS): Pass -g.
* data/skeletons/d.m4 (b4_locations_if): Remove, let bison.m4's one do
its job.
* data/skeletons/lalr1.d (position): Leave filename empty by default.
(position::toString): Don't print empty file names.
(location::this): New ctor.
(location::toString): Match the implementations of C/C++.
(yy_semantic_null): Leave undefined, the previous implementation does
not compile.
* tests/calc.at: Improve the implementation for D.
Enable more checks, in particular using locations.
* tests/local.at (AT_YYERROR_DEFINE(d)): Fix its implementation.
* data/skeletons/lalr1.java: Use more conventional function names for
Java.
Prefer < and <= to => and >.
Use the same approach for m4 quotation as in the other skeletons.
Fix indentation issues.
* tests/calc.at, tests/java.at, tests/javapush.at: Fix quotation style.
(main): Use 'args', not 'argv', the former seems more conventional and
is used elsewhere in Bison.
Prefer character literals to integers to denote characters.
* examples/java/Calc.y: Likewise.
See e3fdc37049: in C++ we generate
explicitly the code for the default action instead of simply copying
blindly the semantic value buffer. This is important when copying
raw memory is not enough, as exemplified by move-only types.
This is currently tested by examples/c++/variant.yy and variant-11.yy.
But it is safer to also have a test in the main test suite.
* tests/local.at (AT_REQUIRE_CXX_STD): Fix.
(AT_BISON_OPTION_PUSHDEFS, AT_BISON_OPTION_POPDEFS): Define/undefine
AT_BISON_OPTIONS.
* tests/c++.at (Default action): New.
It will be convenient to check sets elsewhere.
* tests/sets.at (AT_EXTRACT_SETS): Transform into...
* tests/local.at (AT_SETS_CHECK): this.
* tests/sets.at: Adjust.
It is more consistent with --color=html, --color=test, etc.
* src/getargs.h, src/getargs.c (style_debug): Rename as...
(color_debug): this.
(getargs_colors): Rename --style=debug as --color=debug.
Adjust dependencies.
Currently we remove the rhs to install %empty instead.
* src/reader.c (grammar_rule_check_and_complete): Insert the missing
%empty in front of the rhs, not in replacement thereof.
* tests/actions.at (Add missing %empty): Check that.
* cfg.mk: Disable checks where needed (e.g., we do want to check the
behavior with tabs).
(sc_at_parser_check): Remove. Unfortunately since
a11c144609 we no longer use the './'
prefix to run programs in the current directory. That was so that we
could run Java programs like the other, although they are no run with
the `./` prefix (see 967a59d2c0).
As a consequence this sc check no longer makes sense.
However, since now AT_PARSER_CHECK passes the `./` prefix itself, this
sc-check was superfluous.
* examples/c/reccalc/scan.l: Use memcpy, not strncpy.
* src/ielr.c, src/reader.c: Obfuscate "lr(0)" so that the sc-check for
"space before paren" does not fire.
* tests/diagnostics.at: Avoid space-tab, use tab-tab.
Currently we pass only the columns based on the screen-width, which is
important for the carets. But we don't pass the bytes-based columns,
which is important for the colors. Pass both.
* src/muscle-tab.c (muscle_boundary_grow): Also pass the byte-based column.
* src/location.c (location_caret): Clarify.
(boundary_set_from_string): Adjust to the new format.
* tests/diagnostics.at (Tabulations and multibyte characters from M4): New.
Locations issued from M4 need the byte-based column for the
diagnostics to work properly. Currently they were unassigned, which
typically resulted in partially non-colored diagnostics.
* src/location.c (boundary_set_from_string): Fix the parsed location.
* src/muscle-tab.c (muscle_percent_define_default): Set the byte values.
* tests/diagnostics.at (Locations from M4): New.
Reported by Balázs Scheidler.
* data/skeletons/c.m4 (b4_location_type_define): Use api.location.type
if defined.
* doc/bison.texi: Document it.
* tests/local.at (AT_C_IF, AT_LANG_CASE): New.
Support Span in C.
* tests/calc.at (Span): Convert it to be usable in C and C++.
Check api.location.type with yacc.c and glr.c.
The "identifier and colon" of a rule is implemented as a single token,
but whose location is only that of the identifier (so that messages
about the lhs of a rule are accurate). When reducing empty rules, the
default location is the single point location on the end of the
previous symbol. As a consequence, when Bison parses a grammar, the
location of the right-hand side of an empty rule is based on the
lhs, *independently of the position of the colon*. And the colon can
be way farther, separated by comments, white spaces, including empty
lines.
As a result, some messages look really bad. For instance:
$ cat foo.y
%%
foo : /* empty */
bar
: /* empty */
gives
$ bison -Wall foo.y
foo.y:2.4: warning: empty rule without %empty [-Wempty-rule]
2 | foo : /* empty */
| ^
foo.y:3.4: warning: empty rule without %empty [-Wempty-rule]
3 | bar
| ^
The carets are not at the right column, not even the right line.
This commit passes the colon "again" after the "id colon" token, which
gives more accurate locations for these messages:
$ bison -Wall foo.y
foo.y:2.10: warning: empty rule without %empty [-Wempty-rule]
2 | foo : /* empty */
| ^
foo.y:4.2: warning: empty rule without %empty [-Wempty-rule]
4 | : /* empty */
| ^
* src/scan-gram.l (SC_AFTER_IDENTIFIER): Rollback the colon, so that
we scan it again afterwards.
(INITIAL): Scan colons.
* src/parse-gram.y (COLON): New.
(rules): Parse the colon after the rule's id_colon (and possible
named reference).
* tests/actions.at, tests/conflicts.at, tests/diagnostics.at,
* tests/existing.at: Adjust.
Because the fix-its were ready the character-based columns, but were
applied on byte-based columns, the result with multibyte characters or
tabs could be "interesting". For instance
%fixed-output_files
%fixed_output-files
%fixed-output-files
%define api.prefix {foo}
%no-default-prec
would give
%fixed-%fixed-output-files %fixed_output-files
%fixed-orefix= "foo"
o_default-prec
* src/fixits.c (fixit_print, fixits_run): Work on byte-base columns.
* tests/input.at: Check it.
Currently, when we quote the source file, we indent it with one space,
and preserve tabulations, so there is a discrepancy and the visual
rendering is bad. One way out is to indent with a tab instead of a
space, but then this space can be used for more information. This is
what GCC9 does. Let's play copy cats.
See
https://lists.gnu.org/archive/html/bison-patches/2019-04/msg00025.htmlhttps://developers.redhat.com/blog/2019/03/08/usability-improvements-in-gcc-9/https://gcc.gnu.org/onlinedocs/gccint/Guidelines-for-Diagnostics.html#Guidelines-for-Diagnostics
* src/location.c (location_caret): Prefix quoted lines with the line
number and a pipe, fitting 8 columns.
* tests/actions.at, tests/c++.at, tests/conflicts.at,
* tests/diagnostics.at, tests/input.at, tests/java.at,
* tests/named-refs.at, tests/reduce.at, tests/regression.at,
* tests/sets.at: Adjust expectations.
Partly by "./build-aux/update-test tests/testsuite.dir/*/testsuite.log"
repeatedly, and partly by hand.
This is a pity: efforts were invested in computing correctly the
number of screen columns consumed by multibyte characters, but the
routines that do that were fed by single-byte inputs...
As a consequence Bison never displayed correctly locations when there
are multibyte characters.
* src/scan-gram.l (mbchar): New.
Use it instead of . in the catch-all clause.
* tests/diagnostics.at (Tabulations): Enhance into...
(Tabulations and multibyte characters): this.
Single point locations (equal boundaries) are troublesome, and we were
incorrectly ending the style in their case. Which results in an abort
in libtextstyle.
There is also a confusion between columns as displayed on the
screen (which take into account multibyte characters and tabulations),
and the number of bytes. Counting the screen-column
incrementally (character by character) is uneasy (because of multibyte
characters), and I don't want to maintain a buffer of the current line
when displaying the diagnostic. So I believe the simplest solution is
to track the byte number in addition to the screen column.
* src/location.h, src/location.c (boundary): Add the byte-column.
Adjust dependencies.
* src/getargs.c, src/scan-gram.l: Adjust.
* tests/diagnostics.at: Check zero-width locations.
Enable checking of styles even when libtextstyle is not installed.
* src/getargs.h, src/getargs.c (style_debug): New.
(getargs_colors): Set it when --style=debug.
* src/complain.c (begin_use_class, end_use_class): Use it.
* tests/diagnostics.at: New.
Currently, with --no-lines, instead of "#line file line\n", we emit
"\n". Let's emit nothing.
* data/skeletons/bison.m4 (b4_syncline): Emit at end-of-line when enabled.
* data/skeletons/bison.m4, data/skeletons/c.m4, data/skeletons/glr.cc,
* data/skeletons/lalr1.cc, src/output.c: Use dnl after b4_syncline to
avoid spurious empty lines.
* tests/synclines.at (Sync Lines): Make sure that --no-lines is like
grep -v #line.
* tests/calc.at: Make sure that a rich grammar file behaves properly
with %no-lines.
Currently we use the syncline to report errors about a symbol's
destructor/printer. This is not accurate (only file and line), and
this is incorrect: the file name is double quotes (a recent change,
needed to make sure we escape properly double quotes in it). And
worst of all: with --no-line, b4_syncline expands to nothing.
Rather, push the locations into the backend, and use them.
* src/muscle-tab.h, src/muscle-tab.c (muscle_location_grow): Make it
public.
* src/output.c (prepare_symbol_definitions): Use it to pubish the
location of the printer and destructor.
* data/skeletons/lalr1.java: Use complain_at instead of complain.
* tests/java.at (Java invalid directives): Adjust expectations.
* data/skeletons/bison.m4 (b4_symbol_action_location): Remove.
We should not use b4_syncline this way.
Fatal errors are inconvenient, and should be reserved to cases where
we cannot continue. Here, it could even be warnings actually: these
directives will simply be ignored.
* data/skeletons/lalr1.java: Prefer error (b4_complain) to fatal
errors (b4_fatal).
* tests/java.at (Java invalid directives): New.
Reported by wcventure.
http://lists.gnu.org/archive/html/bug-bison/2019-03/msg00008.html
* src/symtab.c (complain_class_redeclared): Don't print empty
locations.
There can only be empty locations for predefined symbols. And the
only symbol that is lexically available is the error token. So this
appears to be the only possible way to have an error involving an
empty location.
* tests/input.at (Symbol class redefinition): Check it.
The "includes" relation [DeRemer 1982] is between gotos, so of course,
for a given goto, there cannot be more that ngotos (number of gotos)
images. But we manipulate the set of images of a goto as a list,
without checking that an image was not already introduced. So we can
"register" way more images than ngotos, leading to a crash (heap
buffer overflow).
Reported by wcventure.
http://lists.gnu.org/archive/html/bug-bison/2019-03/msg00007.html
For the records, this bug is present in the first committed version of
Bison.
* src/lalr.c (build_relations): Don't insert the same goto several
times.
* tests/sets.at (Build Relations): New.
It seems that not many people read these logs: the error was
introduced in 2001 (3067fbef53),
* src/gram.c (grammar_dump): Fix the headers of the table: remove
duplicate display of "Ritem Range".
While at it, remove duplicate display of the rule number (and remove
an incorrect comment about it: these numbers _are_ equal).
* tests/sets.at (Reduced Grammar): Use useless rule, nterm and token
in the example.
See f8408562f8.
* tests/calc.at: Stop imitating the C API.
Prepare more tests to run in the future.
%verbose works as expected (what a surprise, it's unrelated to the
skeleton...).
