The original Texinfo macros introducing colors were made for
diagnostics, which are printed in bold. So by copy-paste accident the
styles we introduced for counterexamples were also in bold. They
should not.
* doc/bison.texi: Separate the styling of diagnostics from the styling
for counterexamples.
Don't use bold in the latter case.
Unfortunately I found no way to use the ↳ glyph in Texinfo, so I used
@arrow{} instead, which has a different width, so we have to have all
the examples doubled, once for TeX, another for the rest of the world.
* doc/bison.texi: Use the current display in the examples.
* doc/calc.y, doc/ids.y, doc/if-then-else.y, doc/sequence.y: New.
Unfortunately Texinfo somewhat mangles anchors such as `-Werror` into
`g_t_002dWerror`, so let's not include the dash.
* doc/bison.texi (Diagnostics): here.
When reporting counterexamples for s/r conflicts, put the shift first.
This is more natural, and displays the default resolution first, which
is also what happens for r/r conflicts where the smallest rule number
is displayed first, and "wins".
* src/counterexample.c (counterexample): Add a shift_reduce member.
(new_counterexample): Adjust.
Swap the derivations when this is a s/r conflict.
(print_counterexample): For s/r conflicts, prefer "Shift derivation"
and "Reduce derivation" rather than "First/Second derivation".
* tests/conflicts.at, tests/counterexample.at, tests/report.at: Adjust.
* NEWS, doc/bison.texi: Ditto.
It does not make a lot of sense to use ::= in our counterexamples,
that's not something that belongs to the Bison "vocabulary". Using
the colon makes sense, but it's too discreet. Let's use the arrow,
which we already use in some reports (HTML and Dot).
* src/gram.h (print_dot_fallback): Generalize into...
(print_fallback): this.
(print_arrow): New.
* src/derivation.c: Use it.
* NEWS, tests/conflicts.at, tests/counterexample.at,
* tests/diagnostics.at, tests/report.at: Adjust.
* doc/bison.texi: Ditto.
Unfortunately the literal `→` is output as `↦`. So we need to use
@arrow.
* data/bison-default.css: Cobalt does not seem to be supported.
* doc/bison.texi (Counterexamples): A new section.
(Understanding): Show the counterexamples as it shows in the report:
with its items.
(Bison Options): Document -Wcex and -rcex.
In commit c80cdf2db2 ("doc: simplify
uses of @ref", Jan 27 2020, released in Bison 3.6), I broke the
references to the Bibliography. For instance:
For a more detailed exposition of the mysterious behavior in LALR parsers
-and the benefits of IELR, @pxref{Bibliography,,Denny 2008 March}, and
-@ref{Bibliography,,Denny 2010 November}.
+and the benefits of IELR, @pxref{Bibliography}, and
+@ref{Bibliography}.
which results in "see Bibliography" twice, instead of the more precise
reference.
* doc/bison.texi (@pcite, @tcite): New.
Use them instead of @ref to Bibliography.
Cite only the first author (that's what we did for the other entries).
Currently when a push parser finishes its parsing (i.e., it did not
return YYPUSH_MORE), it also clears its state. It is therefore
impossible to see if it had parse errors.
In the context of autocompletion, because error recovery might have
fired, the parser is actually already in a different state. For
instance on `(1 + + <TAB>` in the bistromathic, because there's a
`exp: "(" error ")"` recovery rule, `1 + +` tokens have already been
popped, replaced by `error`, and autocompletions think we are ready
for the closing ")". So here, we would like to see if there was a
syntax error, yet `yynerrs` was cleared.
In the case of a successful parse, we still have a problem: if error
recovery succeeded, we won't know it, since, again, `yynerrs` is
clearer.
It seems much more natural to leave the parser state available for
analysis when there is a failure.
To reuse the parser, we should either:
1. provide an explicit means to reinitialize a parser state for future
parses.
2. automatically reset the parser state when it is used in a new
parse.
Option 2 requires to check whether we need to reinitialize the parser
each time we call `yypush_parse`, i.e., each time we give a new token.
This seems expensive compared to Option 1, but benchmarks revealed no
difference. Option 1 is incompatible with the documentation
("After `yypush_parse` returns a status other than `YYPUSH_MORE`, the
parser instance `yyps` may be reused for a new parse.").
So Option 2 wins, reusing the private `yynew` member to record that a
parse was finished, and therefore that the state must reset in the
next call to `yypull_parse`.
While at it, this implementation now reuses the previously enlarged
stacks from one parse to another.
* data/skeletons/yacc.c (yypstate_new): Set up the stacks in their
initial configurations (setting their bottom to the stack array), and
use yypstate_clear to reset them (moving their top to their bottom).
(yypstate_delete): Adjust.
(yypush_parse): At the beginning, clear yypstate if needed, and at the
end, record when yypstate needs to be clearer.
* examples/c/bistromathic/parse.y (expected_tokens): Do not propose
autocompletion when there are parse errors.
* examples/c/bistromathic/bistromathic.test: Check that case.
Reported by Martin Blais and Yuriy Solodkyy.
https://lists.gnu.org/r/help-bison/2020-05/msg00011.htmlhttps://lists.gnu.org/r/bug-bison/2020-06/msg00038.html
While at it, modernize filename_type as api.filename.type and document
it properly.
* data/skeletons/c++.m4 (filename_type): Rename as...
(api.filename.type): this.
Default to const std::string.
* data/skeletons/location.cc (position, location): Expose the
filename_type type.
Use api.filename.type.
* doc/bison.texi (%define Summary): Document api.filename.type.
(C++ Location Values): Document position::filename_type.
* src/muscle-tab.c (muscle_percent_variable_update): Ensure backward
compatibility.
* tests/c++.at: Check that using const file names is ok.
tests/input.at: Check backward compat.
AFAICT, "dotted rule" is a more frequent synonym of "item" than
"pointed rule". So let's migrate to using "dot" only.
* doc/bison.texi: Use dot/'•' rather than point/'.'.
* src/print-xml.c (print_core): Use dot rather than point. This is
not backward compatible, but AFAICT, we don't have actual user of the
XML output (but ourselves). So...
* data/xslt/xml2dot.xsl, data/xslt/xml2text.xsl,
* data/xslt/xml2xhtml.xsl, tests/report.at: ... adjust.
While defining api.header.include worked as expected, its default
value was incorrectly defined. As a result, by default, the generated
parsers still duplicated the content of the generated header instead
of including it.
* data/skeletons/yacc.c (api.header.include): Fix its default value.
* tests/output.at: Check it.
* doc/bison.texi (%define Summary): Document api.header.include.
While at it, move the definition of api.namespace at the proper
place.
In Bison we refer to "shift/reduce" conflicts, not "shift-reduce" (in
Bison 3.6.3 186 occurrences vs 15). Enforce consistency on this.
Instead of "spending" a second line for each conflict to report the
lookaheads, put that on the same line as the type of conflict. Also,
prefer "token" to "symbol". Maybe we should even prefer "lookahead".
While at it, enable internationalization, with plurals where
appropriate.
As a consequence, instead of
Shift-Reduce Conflict:
6: 3 b: . %empty
6: 6 d: c . A
On Symbol: A
display
Shift/reduce conflict on token A:
6: 3 b: . %empty
6: 6 d: c . A
* NEWS, doc/bison.texi, src/conflicts.c: Spell it "shift/reduce", not
"shift-reduce".
* src/counterexample.c (counterexample_report_shift_reduce)
(counterexample_report_reduce_reduce): Reformat and internationalize
output.
* tests/counterexample.at: Adjust expectations.
* upstream/maint:
maint: post-release administrivia
version 3.6.3
build: check -Wmissing-prototypes
tests: show logs
c++: fix printing of state number on streams
pstate_clear is lacking a prototype.
Reported by Ryan
https://lists.gnu.org/r/bug-bison/2020-05/msg00101.html
Besides, none of the C examples were compiled with the warning flags.
* configure.ac (warn_c): Add -Wmissing-prototypes.
* data/skeletons/yacc.c (pstate_clear): Make it static.
* examples/local.mk (TEST_CFLAGS): New.
* examples/c/bistromathic/local.mk, examples/c/calc/local.mk,
* examples/c/lexcalc/local.mk, examples/c/mfcalc/local.mk,
* examples/c/pushcalc/local.mk, examples/c/reccalc/local.mk,
* examples/c/rpcalc/local.mk:
Use it.
GCC's warn_unused_result is not silenced by a cast to void, so we have
to "use" scanf's result.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=25509https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66425
Flex generated code produces too many warnings, including things such
as, with ICC:
examples/c/lexcalc/scan.c(1088): error #1682: implicit conversion
of a 64-bit integral type to a smaller integral type (potential portability problem)
2259 YY_INPUT( (&YY_CURRENT_BUFFER_LVALUE->yy_ch_buf[number_to_move]),
2260 ^
2261
2262
I am tired of trying to fix Flex's output. The project does not seem
maintained. We ought to avoid it. So, for the time being, don't try
to enable warnings with Flex.
* examples/c/bistromathic/parse.y, examples/c/reccalc/scan.l: Fix
warnings.
* doc/bison.texi: Discard scanf's return value to defeat
-Werror=unused-result.
Teaches bison about a new command line option, --file-prefix-map OLD=NEW
(based on the -ffile-prefix-map option from GCC) which causes it to
replace and file path of OLD in the text of the output file with NEW,
mainly for header guards and comments. The primary use of this is to
make builds reproducible with different input paths, and in particular
the debugging information produced when the source code is compiled. For
example, a distro may know that the bison source code will be located at
"/usr/src/bison" and thus can generate bison files that are reproducible
with the following command:
bison --output=/build/bison/parse.c -d --file-prefix-map=/build/bison/=/usr/src/bison/ parse.y
Importantly, this will change the header guards and #line directives
from:
#ifndef YY_BUILD_BISON_PARSE_H
#line 100 "/build/bison/parse.h"
to
#ifndef YY_USR_SRC_BISON_PARSE_H
#line 100 "/usr/src/bison/parse.h"
which is reproducible.
See https://lists.gnu.org/r/bison-patches/2020-05/msg00016.html
Signed-off-by: Joshua Watt <JPEWhacker@gmail.com>
* src/files.h, src/files.c (spec_mapped_header_file)
(mapped_dir_prefix, map_file_name, add_prefix_map): New.
* src/getargs.c (-M, --file-prefix-map): New option.
* src/output.c (prepare): Define b4_mapped_dir_prefix and
b4_spec_header_file.
* src/scan-skel.l (@ofile@): Output the mapped file name.
* data/skeletons/glr.c, data/skeletons/glr.cc,
* data/skeletons/lalr1.cc, data/skeletons/location.cc,
* data/skeletons/yacc.c:
Adjust.
* doc/bison.texi: Document.
* tests/input.at, tests/output.at: Check.
* etc/bench.pl.in, examples/c/bistromathic/parse.y,
* examples/c/calc/calc.y, examples/c/pushcalc/calc.y: Check scanf's
return value.
* doc/bison.texi: Likewise, but only for the second example, to avoid
cluttering the very simple case.
I don't think it's fair to have yypstate_new, yypstate_delete,
yypush_parse and yypull_parse to have their own section, on par with
yyparse and yylex. Let them be in a single section about push
parsers. And show new/delete first.
* doc/bison.texi (Push Parser Interface): New.
Fuse the aforementioned sections into it.
The user gives yyexpected_tokens a limit: the max number of tokens she
wants to hear about. That's because an error message that reports a
bazillion of possible tokens is useless.
In that case yyexpected_tokens returned 0, so the user would not know
if there are too many expected tokens or none (yes, that's possible).
There are several ways to tell the user in which situation she's in:
- return some E2MANY, a negative value. Then it makes the pattern
int argsize = yypcontext_expected_tokens (ctx, arg, ARGS_MAX);
if (argsize < 0)
return argsize;
no longer valid, as for E2MANY (i) the user must generate the error
message anyway, and (ii) she should not return E2MANY
- return ARGS_MAX + 1. Then it makes it dangerous for the user, as
she has to iterate update `min (ARGS_MAX, argsize)`.
Returning 0 is definitely simpler and safer for the user, as it tells
her "this is not an error, just generate your message without a list
of expecting tokens". So let's still return 0, but set arg[0] to the
empty token when the list is really empty.
* data/skeletons/glr.c, data/skeletons/lalr1.cc, data/skeletons/lalr1.java
* data/skeletons/yacc.c (yyexpected_tokens): Put the empty symbol
first if there are no possible tokens at all.
* examples/c/bistromathic/parse.y: Demonstrate how to use that.
* data/skeletons/lalr1.java (Location): Make it a static class.
(Lexer.yylex, Lexer.getLVal, Lexer.getStartPos, Lexer.getEndPos):
These are not needed in push parsers.
* examples/java/calc/Calc.y: Demonstrate push parsers in the Java.
* doc/bison.texi: Push parsers have been supported for a long time,
remove incorrect statements stating the opposite.
We will not keep YYERRCODE anyway, it causes backward compatibility
issues. So as a first step, let all the skeletons use that name,
until we have a better one.
* data/skeletons/bison.m4, data/skeletons/glr.c,
* data/skeletons/glr.cc, data/skeletons/lalr1.cc,
* data/skeletons/lalr1.d, data/skeletons/lalr1.java,
* data/skeletons/yacc.c, doc/bison.texi, tests/headers.at,
* tests/input.at:
here.
