* src/lalr.c: Move logs to a better place to understand the chronology
of events.
* src/symlist.c (symbol_list_syms_print): Don't dump core on type
elements.
The 'regen' commit in Bison's history are a nuisance. They are
especially big because of the #lines. Let's generate our parse
without these lines in the repository, but generate them in the
tarball.
* Makefile.am (AM_YFLAGS_WITH_LINES): New.
(AM_YFLAGS): Use it.
(dist-hook): Regenerate the parser with #lines.
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.
I never understood why we book ngotos+1 slots for relations between
gotos: there are at most ngotos images, not ngotos+1 (and "includes"
does have cases where a goto is in relation with itself, so it's not
ngotos-1).
Maybe bbf37f2534 explains the +1: a bug
left us register a goto several times on occasion, and the +1 might
have been a means to avoid this problem in most cases. Now that this
bug is addressed, we should no longer overbook memory, if only for the
clarity of the code ("why ngotos+1 instead of ngotos?").
* src/lalr.c: A goto has at most ngotos images, not ngotos+1.
While at it, avoid useless repeated call to map_goto introduced in
bbf37f2534.
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.
When we update some output format, too many adjustements must be made
by hand. This script updates most tests based on the actual output
made during the tests.
* build-aux/update-test: New.
* src/reader.c (grammar_rule_check_and_complete): When 'p' and 'lhs'
are aliases, prefer the latter, for clarity and consistency.
(grammar_current_rule_begin): Avoid 'p', current_rule suffices.
* src/gram.h, src/gram.c: Comment changes.
ptdr# calc.tab.c
Bruno Haible just added a default implementation of libtextstyle's
interface when the library is not available.
https://lists.gnu.org/archive/html/bison-patches/2019-03/msg00025.html
* gnulib: Update.
* bootstrap.conf: Replace libtextstyle with libtextstyle-optional.
* src/complain.c, src/getargs.c: Remove now useless cpp guards.
The timevar and bitset modules now use the c99 module which causes
$CXX to now include -std=gnu++11 when possible. Unfortunately, G++
4.7 does not implement [[noreturn]] in C++11 mode, so our tests of
glr.cc (which uses _Noreturn) fail with
input.cc:954:1: error: expected unqualified-id before '[' token
right before [[noreturn]]. 4.8 works fine.
* data/skeletons/c.m4 (b4_attribute_define): Do not use [[noreturn]]
with GCC 4.7.
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...).
The variable spec_defines_file denotes the name of the generated
header. Its name is derived from --defines/%defines, whose name in
turn is derived from the fact that the header, in Yacc, contained the
Not only does the header now contain a lot more than just the token
definitions, but we no longer even generate macros, but an enum...
Let's modernize our vocabulary.
* src/files.h, src/files.c (spec_defines_file): Rename as...
(spec_header_file): this.
Currently when --defines is used, we generate a header, and paste an
exact copy of it into the generated parser implementation file. Let's
provide a means to #include it instead.
We don't do it by default because of the Autotools' ylwrap. This
program wraps invocations of yacc (that uses a fixed output name:
y.tab.c, y.tab.h, y.output) to support a more modern naming
scheme (dir/foo.y -> dir/foo.tab.c, dir/foo.tab.h, etc.). It does
that by renaming the generated files, and then by running sed to
propagate these renamings inside the files themselves.
Unfortunately Automake's Makefiles uses Bison as if it were Yacc (with
--yacc or with -o y.tab.c) and invoke bison via ylwrap. As a
consequence, as far as Bison is concerned, the output files are
y.tab.c and y.tab.h, so it emits '#include "y.tab.h"'. So far, so
good. But now ylwrap processes this '#include "y.tab.h"' into
'#include "dir/foo.tab.h"', which is not guaranteed to always work.
So, let's do the Right Thing when the output file is not y.tab.c, in
which case the user should %define api.header.include. Binding this
behavior to --yacc is tempting, but we recently told people to stop
using --yacc (as it also enables the Yacc warnings), but rather to use
-o y.tab.c.
Yacc.c is the only skeleton concerned: all the others do include their
header.
* data/skeletons/yacc.c (b4_header_include_if): New.
(api.header.include): Provide a default value when the output is not
y.tab.c.
* src/parse-gram.y (api.header.include): Define.
Running with CC='gcc-mp-8 -fsanitize=undefined' revealed Undefined
Behaviors.
https://lists.gnu.org/archive/html/bison-patches/2019-03/msg00008.html
* src/state.c (errs_new): Don't call memcpy with NULL as source.
* src/location.c (add_column_width): Don't assume that the column
argument is nonnegative: the scanner sometimes "backtracks" (e.g., see
ROLLBACK_CURRENT_TOKEN and DEPRECATED) in which case we can have
negative column numbers (temporarily).
Found in test 3 (Invalid inputs).
* data/skeletons/yacc.c: here.
This is more logical for the time stamps, but it's also required by
following patches: the shared declarations are also in charge of
handling api.value.type=union. So far, they are run in the
implementation file in both cases (with or without header). But if we
run them only in the header, then the implementation file is emited
with incorrect support for api.value.type=union.
Arguably we should not have such dependencies. This is because we
have side-effects in our backend (redefining the symbols' type and
type_tag). In the future we should find a better solution for this,
without sacrificing the independence of the backend from bison
itself (i.e., I don't think we should handle api.value.type=union in
bison, leave it to m4).
Currently we generate things like:
#line 683 "src/parse-gram.y" /* yacc.c:316 */
The first part is of course very important: compilers point the users
to their grammar file rather than into the generated parser. The
second part points to the place in the skeletons that generated this
piece of code.
This dependency on the Bison skeletons generates lots of useless 'git
diff'. This location is useless for the regular user (who does not
care about the skeletons) and is actually not useful for Bison
developpers too (I never used this to locate the code in skeletons
that generated output). So disable it completely. If someone thinks
this was actually useful, a %define variable should be provided to
control the level of verbosity of '#line', in replacement of
--no-lines.
So now, generate:
#line 683 "src/parse-gram.y"
* data/skeletons/bison.m4 (b4_sync_end): Emit nothing.
* src/lalr.c (follows_print): Just print the symbol tag.
Take and print a title.
Indent the output.
Use it to print the various steps of the computation.
(lookahead_tokens_print): Fix a lie: the number displayed is not the
number of tokens.
Don't display states that don't even have reductions.
* src/relation.h, src/relation.c (relation_print): Accept and use a
title.
Don't print empty rows.
Indent the output.
Adjust dependencies.
* src/lalr.c (initialize_goto_follows): Print 'reads' in traces.
* configure.ac (DCFLAGS): Define.
* tests/atlocal.in: Receive it.
* data/skeletons/d.m4 (api.parser.class): Remove spurious YY.
* data/skeletons/lalr1.d (yylex): Return an int instead of a
YYTokenType, so that we can use characters as tokens.
* examples/d/calc.y: Adjust.
* tests/local.at: Initial support for D.
(AT_D_IF, AT_DATA_GRAMMAR(D), AT_YYERROR_DECLARE(d))
(AT_YYERROR_DECLARE_EXTERN(d), AT_YYERROR_DEFINE(d))
(AT_MAIN_DEFINE(d), AT_COMPILE_D, AT_LANG_COMPILE(d), AT_LANG_EXT(d)):
New.
* tests/calc.at: Initial support for D.
* tests/headers.at
* examples/d/calc.y: Exit with failure on errors.
Remove useless operators (=, !) meant for the test suite.
Add unary + for symmetry.
* examples/d/calc.test: Adjust expectations.
Commit db34f79889 renames the variable F
as goto_follows, but forgot to rename this function.
* src/lalr.c (initialize_F): Rename as...
(initialize_goto_follows): this.
I need to be able to read includes and goto_follows.
* src/relation.h, src/relation.c (relation_print): Provide a means to
pretty-print the nodes of the relation.
* src/lalr.c (goto_print, follows_print): New.
(set_goto_map): Use goto_print.
(build_relations): Show INCLUDES.
(compute_FOLLOWS): Rename as...
(compute_follows): this.
Show FOLLOWS.
* src/lalr.c (build_relations): Reduce the scopes.
Instead of keeping rp alive in two different loops, clarify the second
one by having an index on the path we traverse (i.e., use that index
to compute the source state _and_ the symbol that labels the
transition).
This allows to turn an obscure 'while'-loop in a clearer (IMHO)
'for'-loop. We also consume more variables (by introducing p instead
of making more side effects on length), but we're in 2019, I don't
think this matters. What does matter is that (IMHO again), this is
now clearer.
Also, use clearer names.
* tests/local.at (AT_MAIN_DEFINE(java)): Exit failure on failure.
(AT_PARSER_CHECK): If in Java, run AT_JAVA_PARSER_CHECK.
* tests/conflicts.at (AT_CONSISTENT_ERRORS_CHECK): Simplify.
Currently the caller must specify the ./ prefix to its command. Let's
avoid that: it will be nicer to read, make it easier to have a version
that works for Java and C/C++.
* tests/local.at (AT_PARSER_CHECK): Prefix the command with ./.
Adjust callers.
* tests/conflicts.at (AT_YYLEX_PROTOTYPE): Don't define it, leave that
task to AT_DATA_GRAMMAR.
But be honest: tell AT_BISON_OPTION_PUSHDEFS all the options we use.
Reported by Hans Åberg.
https://lists.gnu.org/archive/html/help-bison/2019-02/msg00064.html
* src/files.c (spec_graph_file): Use `*.gv` when 3.4 or better,
otherwise `*.dot`.
* src/parse-gram.y (handle_require): Pretend we are already 3.4.
* doc/bison.texi: Adjust.
* tests/local.at, tests/output.at: Exercise this.
Currently, we have errors:
./doc/bison.texi:13005: node `History' lacks menu item for `Yacc' despite being its Up target
* doc/bison.texi (History): Add the local menu.
While at it, add a few index entries.
* examples/c/lexcalc/parse.y: Formatting/comment changes.
(line): Don't return a value.
Print the result here, which avoids printing a value for lines with an
error.
(yyerror): Be sure to increment the pointed, not the pointer...
* examples/c/lexcalc/lexcalc.test: Check errors.
* examples/c/lexcalc/local.mk: Fix a dependency.
While hacking on the computation of the automaton, I had yystate being
equal to -1, and the parser loops. Let's catch this when
parser.assert is enabled.
* data/skeletons/yacc.c (YY_ASSERT): New.
Use it.
Not using the name YYASSERT, to make it clear that this is private.
glr.c should probably move to YY_ASSERT too.
Also, while at it, report 'Entering state...' even before growing the
stacks.
* examples/c/calc/local.mk, examples/c/lexcalc/local.mk,
* examples/c/mfcalc/local.mk, examples/c/rpcalc/local.mk:
Regenerate the files if dependencies have changed.
I don't think this style:
/* If buffer is full, make it bigger. */
if (i == length)
{
length *= 2;
symbuf = (char *) realloc (symbuf, length + 1);
}
/* Add this character to the buffer. */
symbuf[i++] = c;
/* Get another character. */
c = getchar ();
or more readable than
/* If buffer is full, make it bigger. */
if (i == length)
{
length *= 2;
symbuf = (char *) realloc (symbuf, length + 1);
}
/* Add this character to the buffer. */
symbuf[i++] = c;
/* Get another character. */
c = getchar ();
Actually, I think the latter is more readable, and helps with width
issues in the PDF. As a matter of fact, I would happily move to //
only for single line comments.
* doc/bison.texi: A single space before closing comments.
* doc/bison.texi: Prefer 'fun' to 'fnct'.
Reduce local variable scopes.
Prefer strdup to malloc + strcpy.
Avoid gratuitous casts.
Use simpler names (e.g., 'name' instead of 'fname').
Avoid uses of 0 for NULL.
Avoid using NULL when possible (e.g., 'p' instead of 'p != NULL').
Prefer union names to casts (e.g. 'yylval.VAR = s' instead of
'*((symrec**) &yylval) = s').
Give arguments a name in fun declarations.
Use our typedefs instead of duplicating them (func_t).
Stop promoting an explicit $$ = $1;, it should be implicit (Bison
might be able to eliminate useless chain rules).
Help a bit Texinfo by making smaller groups.
Rely on the C compiler to call function pointers (prefer
'$1->value.fun ($3)' to (*($1->value.fnctptr))($3)').
Currently we have no simple example: rpcalc in reverse Polish, mfcalc
has functions, and lexcalc is using lex.
* examples/c/calc/Makefile, examples/c/calc/calc.y,
* examples/c/calc/calc.test, examples/c/calc/local.mk: New.
* examples/extexi: Since we issue #lines only at the beginning of
@example, leave empty line when removing content (such as @comment
lines), otherwise the lines that follow have incorrect source line
location. This leaves ugly empty lines, but they are removed when you
tidy the output for the end user: sequences of \n are mapped to at
most two sucessive \n.
The format is inconsistent. For instance most sections are
indented (including "Terminals unused in grammar" for instance), but
the sections "Terminals, with rules where they appear" and
"Nonterminals, with rules where they appear" are not. Let's indent
them. Also, these two sections try to wrap the output to avoid lines
too long. Yet we don't do that in the rest of the file, for instance
when listing the lookaheads of an item.
For instance in the case of Bison's parse-gram.output we go from:
Terminals, with rules where they appear
"end of file" (0) 0
error (256) 28 88
"string" <char*> (258) 9 13 16 17 20 23 24 109 116
[...]
Nonterminals, with rules where they appear
$accept (58)
on left: 0
input (59)
on left: 1, on right: 0
prologue_declarations (60)
on left: 2 3, on right: 1 3
prologue_declaration (61)
on left: 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 22 23 24
25 26 27 28 29, on right: 3
[...]
to
Terminals, with rules where they appear
"end of file" (0) 0
error (256) 28 88
"string" <char*> (258) 9 13 16 17 20 23 24 109 116
[...]
Nonterminals, with rules where they appear
$accept (58)
on left: 0
input (59)
on left: 1
on right: 0
prologue_declarations (60)
on left: 2 3
on right: 1 3
prologue_declaration (61)
on left: 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 22 23 24 25 26 27 28 29
on right: 3
[...]
* src/print.c (END_TEST): Remove.
(print_terminal_symbols): Don't try to wrap the output.
(print_nonterminal_symbols): Likewise.
Make two different lines for occurrences on the left, and occurrence
on the rhs of the rules.
Indent by 4 and 8, not 3.
* src/reduce.c (reduce_output): Indent by 4, not 3.
* tests/conflicts.at, tests/existing.at, tests/reduce.at,
* tests/regression.at, tests/report.at:
Adjust.
This should not be used to generate parsers. My point is actually to
facilitate debugging (when tweaking the generation of the LR(0)
automaton for instance, not carying -yet- about lookaheads).
* src/reader.c (prepare_percent_define_front_end_variables): Add lr(0).
* src/conflicts.c (set_conflicts): Be robust to reds not having
lookaheads at all.
* src/ielr.c (LrType, lr_type_get): Adjust.
(ielr): Implement support for LR(0).
* src/lalr.c (lalr_free): Don't free LA when it's not computed.
* maint:
maint: post-release administrivia
version 3.3.2
style: minor fixes
NEWS: named constructors are preferable to symbol_type ctors
gram: fix handling of nterms in actions when some are unused
style: rename local variable
CI: update the ICC serial number for travis-ci.org
Akim Demaille