When using glr.cc, the C function yyparse is an internal detail that
should not be exposed. Users might call it by accident (I did).
* data/skeletons/glr.c (yyparse): When used for glr.cc, rename as yy_parse_impl.
* data/skeletons/glr.cc: Adjust.
The yydefgoto table uses -1 as an invalid for an impossible case (we
never use yydefgoto[0], since it corresponds to the reduction to
$accept, which never happens). Since yydefgoto is a table of state
numbers, this -1 forces a signed type uselessly, which (1) might
trigger compiler warnings when storing a value from yydefgoto into a
state number (nonnegative), and (2) wastes bits which might result in
using a int16 where a uint8 suffices.
Reported by Jot Dot <jotdot@shaw.ca>.
https://lists.gnu.org/r/bug-bison/2020-11/msg00027.html
* src/tables.c (default_goto): Use 0 rather than -1 as invalid value.
* tests/regression.at: Adjust.
* data/skeletons/lalr1.d (YYLocation.step): New.
* examples/d/calc/calc.y (Lexer): Reduce scopes to avoid uninitialized
varibles.
Factor the handling of locations.
We don't need lenChars.
Suggested by Joe Nelson <joe@begriffs.com>.
https://lists.gnu.org/r/help-bison/2020-12/msg00020.html
* data/skeletons/glr.c, data/skeletons/yacc.c (YYNOMEM): New.
Use it.
(yyexhaustedlab): Rename as...
(yynomemlab): this.
* tests/calc.at: Check it.
* doc/bison.texi: Document it.
Fix incorrect statements about non-existing constants for YYERROR etc.
There are some tests that cover them, but nothing for all the
skeletons. Let's do that in the calculator tests.
* tests/calc.at: Check YYACCEPT and YYABORT.
I am not aware of people subclassing the parser class, and I fail to
see how this could be useful. Rather than leaving a badly baked
feature (as in glr.cc currently), let's not support it at all, until
someone comes and explains why and how it would be useful.
* data/skeletons/glr2.cc (parser): We need no virtual function members.
It's on purpose that I keep the `this->` now. We'll see later if we
want to remove them.
* data/skeletons/glr2.cc (yygetToken): Move into...
(glr_stack::yyget_token): this.
(b4_lex): Adjust.
Currently we have two classes that actually should be fused together:
parser and glr_stack. Both carry part of the parsing: (i) parser
contains `parse`, which is the top-level of the parsing process, it
uses yygetToken, etc., and (ii) glr_stack takes care of all the
details (dealing with the stack), and also calls yygetToken.
However if we fuse them together, we would get a large parser class,
in the header file. So it is probably better to split this large
class using the pimpl idiom. But then it appears that glr_stack is
very close from being the impl of parser.
Let's improve this.
For a start...
* data/skeletons/glr2.cc (parser::parse): Move to...
(glr_stack::parse): here.
(parser::parse): Use it.
When comparing traces from different machines, the mixture of
stdout/stderr in the output are making things uselessly difficult.
* src/lssi.c, src/state-item.c: Output debug traces on stderr.
* data/skeletons/glr2.cc: We no longer play dirty tricks with
parse-params, remove the now useless dance around them.
We now have genuine objects for locations, leave the initial action
alone.
* data/skeletons/glr2.cc: Add support for api.token.constructor.
* examples/c++/glr/c++-types.yy: Use it.
* examples/c++/glr/c++-types.test: Adjust expectations for error
messages.
* data/skeletons/c++.m4 (b4_yytranslate_define): Use static_cast
rather than the YY_CAST macro.
Avoids the need to define YY_CAST in the header.
* data/skeletons/glr2.cc: Fix calls to b4_shared_declarations: pass
the type of file we are in.
Don't define YYTRANSLATE.
(parser::yytranslate_): New, as in lalr1.cc.
Adjust to use it.
* tests/glr-regression.at: Adjust.
Instead of tracking the lookahead with yychar, use yytoken. This is
consistent with lalr1.cc, saves us from calls to YYTRANSLATE (except
when calling yylex), and makes it easier to migrate to using
symbol_type.
* data/skeletons/glr2.cc: Replace all uses of `int yychar` with
`symbol_kind_type yytoken`.
(yygetToken): Don't take/return the lookahead's token-kind and
symbol-kind, just work directly on yystack's `yytoken` member.
* tests/glr-regression.at (AT_PRINT_LOOKAHEAD_DECLARE)
(AT_PRINT_LOOKAHEAD_DEFINE): New.
Adjust to the fact that we have yytoken, not yychar, in glr2.cc.
* data/skeletons/glr2.cc (b4_symbol_action): New, so that we use
`yyval` and `yyloc` rather than the `yyvaluep` and `yylocationp`
pointers.
(yy_symbol_value_print_, yy_symbol_print_, yy_destroy_): Use
references rather than pointers.
Drop support for the undocumented, obsolete, `yyoutput` variable.
Adjust callers.
(glr_state::destroy): Don't use yy_symbol_print_ when we don't have a
symbol. Rather, write dedicated code.
The locations are actually false: they should include the location of
the semicolon (we print statements), but they don't.
* examples/c++/glr/c++-types.test, examples/c++/glr/c++-types.yy,
* examples/c/glr/c++-types.test, examples/c/glr/c++-types.y,
* tests/cxx-type.at:
Fix locations and adjust expectations.
This will be useful to support changes in glr2.cc.
tests/glr-regression.at
(Incorrect lookahead during deterministic GLR)
(Incorrect lookahead during nondeterministc GLR):
Introduce and use PRINT_LOOKAHEAD.