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.
Reported by Dwight Guth.
https://lists.gnu.org/r/bug-bison/2020-06/msg00037.html
* src/AnnotationList.c (AnnotationList__computePredecessorAnnotations):
Beware that SBITSET__FOR_EACH nests _two_ for-loops, so "break" does
not actually break out of it.
That was the only occurrence in the code.
* src/Sbitset.h (SBITSET__FOR_EACH): Warn passersby.
* upstream/maint:
maint: post-release administrivia
version 3.6.4
glr.cc: don't leak glr.c/glr.cc scaffolding to the user
Some fixes were needed to adjust to recent changes in glr.cc and
glr.c.
* data/skeletons/glr.cc: Stop messing with the user's epilogue to
insert glr.cc code. We need that code to be inserted _before_ the
user's epilogue, not after. So define b4_glr_cc_pre_epilogue.
* data/skeletons/glr.c: Use it.
Until we have a decent reimplementation of glr.cc, we have to use
tricks to shoehorn C++ symbols to the C engine of glr.c. Some of them
are done via #define. Unfortunately in Bison 3.6 some of these we
done in the header file, which broke valid user code.
Reported by Egor Pugin.
https://lists.gnu.org/r/bug-bison/2020-06/msg00003.html
* data/skeletons/glr.cc: Stop playing tricks with b4_pre_epilogue.
(b4_glr_cc_setup, b4_glr_cc_cleanup): New.
Much cleaner way to instal glr.cc's scaffolding around glr.c.
* data/skeletons/glr.c: Adjust to use them.
From
"number" shift, and go to state 1
"Ñùṃéℝô" shift, and go to state 2
to
"number" shift, and go to state 1
"Ñùṃéℝô" shift, and go to state 2
* src/print.c: Use mbswidth, not strlen, to compute visual columns.
* 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.
Commit a4ede8f85b ("package: make bison
a relocatable package") made Bison relocatable, but in fact it still
contains one absolute reference: the M4 variable, which points to the
M4 program. Let's fix that by using relocate(), see if an M4 binary is
available at the relocated location, and otherwise fallback to the
original M4 location.
See https://lists.gnu.org/r/bison-patches/2020-05/msg00078.html,
and https://lists.gnu.org/r/bison-patches/2020-05/msg00087.html.
* src/files.h, src/files.c (m4path): New.
* src/output.c: Use it.
With input such as
%token<fl> yVL_CLOCK "/*verilator sc_clock*/"
we generate
yVL_CLOCK = 610, /* "/*verilator sc_clock*/" */
which is invalid since the comment will actually be closed on the
first "*/". Let's turn "*/" into "*\/" to avoid this. But GCC will
also warn about "/*" inside a comment, so let's "escape" it too.
Reported by Huang Rui.
https://github.com/akimd/bison/issues/38
* data/skeletons/c-like.m4 (_b4_comment): Escape comment delimiters in
comments.
* tests/input.at (Torturing the Scanner): Check thes cases.
* tests/m4.at: New.
Reported by Martin Blais <blais@furius.ca>.
https://lists.gnu.org/r/help-bison/2020-05/msg00005.html
* data/skeletons/lalr1.cc (symbol_name): Make it public.
Add a private hidden hook to enable testing of private parts.
* tests/local.at (AT_DATA_GRAMMAR_PROLOGUE): Help Emacs find the right
language mode.
* tests/c++.at (C++ Variant-based Symbols Unit Tests): Check that we
can read symbol_name.
* 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.
