Suggesting -Wcounterexamples when there are conflicts is probably not
what the user wants. If she knows her conflicts and has set
%expect/%expect-rr appropriately, we shouldn't warn.
The commit also swaps the counterexamples and the report of conflicts,
into, IMHO, a more natural order: from
Shift/reduce conflict on token B:
1: 3 a: A .
1: 8 y: A . B
Example A • B C
First derivation s ::=[ a ::=[ A • ] x ::=[ B C ] ]
Example A • B C
Second derivation s ::=[ y ::=[ A • B ] c ::=[ C ] ]
input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
input.y:4.4: warning: rule useless in parser due to conflicts [-Wother]
to
input.y: warning: 1 shift/reduce conflict [-Wconflicts-sr]
Shift/reduce conflict on token B:
1: 3 a: A .
1: 8 y: A . B
Example A • B C
First derivation s ::=[ a ::=[ A • ] x ::=[ B C ] ]
Example A • B C
Second derivation s ::=[ y ::=[ A • B ] c ::=[ C ] ]
input.y:4.4: warning: rule useless in parser due to conflicts [-Wother]
* src/conflicts.c (rule_conflicts_print): Rename as...
(report_rule_expectation_mismatches): this.
Move the handling of report_counterexamples to...
(conflicts_print): Here.
Display this warning when applicable.
Plural vs. singular is always a problem...
But we already have conflicts-sr and conflicts-rr, so counterexamples
makes more sense than counterexample. Besides, -Wcounterexample will
still be accepted as an unambiguous prefix of -Wcounterexamples.
Add -Wcex as a convenient alias.
While at it, use only "counterexample", never "counter example".
* src/complain.h, src/complain.c
(Wcounterexample, warning_counterexample): Rename as...
(Wcounterexamples, warning_counterexamples): these.
(argmatch_warning_docs): Rename -Wcounterexample as -Wcounterexamples.
(argmatch_warning_args): Likewise.
Add support for -Wcex.
Adjust dependencies.
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.
Use colors to show the counterexamples and the derivations in color,
to highlight their structure. Align the outputs, and add i18n
support. Reduce width by using a one-space separator instead of
two-space.
From
Example A • B C
First derivation s ::=[ a ::=[ A • ] x ::=[ B C ] ]
Second derivation s ::=[ y ::=[ A • B ] c ::=[ C ] ]
to
Example A • B C
First derivation s ::=[ a ::=[ A • ] x ::=[ B C ] ]
Example A • B C
Second derivation s ::=[ y ::=[ A • B ] c ::=[ C ] ]
with colors.
* data/bison-default.css (cex-dot, cex-0, cex-1, cex-2, cex-3, cex-4)
(cex-5, cex-6, cex-7, cex-step, cex-leaf): New.
* src/derivation.c (derivation_print_styled_impl): New.
(derivation_print, derivation_print_leaves): Use it.
* src/counterexample.c: Reformat the output.
* tests/counterexample.at: Adjust.
It's unfortunate that the traditions between formal language theory
and Yacc differs, but here, tokens should be upper case, and
nonterminals should be lower case.
* tests/counterexample.at: Comply with this.
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.
For instance, in the case of Bison's own parser:
- case 40:
+ case 40: /* grammar_declaration: "%code" "identifier" "{...}" */
{
muscle_percent_code_grow ((yyvsp[-1].ID), (yylsp[-1]),
translate_code_braceless ((yyvsp[0].BRACED_CODE), (yylsp[0])),
(yylsp[0]));
code_scanner_last_string_free ();
}
break;
* data/skeletons/c.m4: Modified.
* data/skeletons/d.m4: Modified.
* data/skeletons/java.m4: Modified.
* src/output.c (output_escaped): New.
(quoted_output): Use it, and rename as...
(output_quoted): this.
Adjust dependencies.
(rule_output): New.
(user_actions_output): Use it.
* data/skeletons/c.m4, data/skeletons/d.m4, data/skeletons/java.m4
(b4_case): Add support for $3, an optional comment.
We were still using GCC9, because GCC10 was failing.
* .travis.yml (PPC64le): Use GCC10.
While at it, use -O2 instead of -O3: it's certainly nicer for the
CPUs, and allows to test different sets of compiler flags (we use -O3
in several other configurations).
* 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
First, we should avoid code such as
gl_list_iterator_t it = gl_list_iterator (deriv->children);
derivation *child = NULL;
while (gl_list_iterator_next (&it, (const void **) &child, NULL))
{
derivation_print (child, f);
because of -Wstrict-aliasing (whose job is to catch type-punning
issues). See https://lists.gnu.org/r/bug-bison/2020-05/msg00039.html.
Rather we need
gl_list_iterator_t it = gl_list_iterator (deriv->children);
const void **p = NULL;
while (gl_list_iterator_next (&it, &p, NULL))
{
derivation *child = (derivation *) p;
derivation_print (child, f);
Second, list iterators actually have destructors. Even though they
are noop in the case of linked-lists, we should use them.
Let's address both issues with typed wrappers (such as
derivation_list_next) that take care of both issues, and besides allow
to scope the iterators within the loop:
derivation *child;
for (gl_list_iterator_t it = gl_list_iterator (deriv->children);
derivation_list_next (&it, &child);
)
{
derivation_print (child, f);
* src/derivation.h, src/derivation.c (derivation_list_next): New.
Use it where appropriate.
* src/counterexample.c (search_state_list_next): New.
Use it where appropriate.
* src/parse-simulation.h, src/parse-simulation.c
* src/state-item.h (state_item_list_next): New.
Use it where appropriate.
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.
item_number is used for elements of ritem as well as indices into
ritem which is fairly confusing. Introduce item_index to represent
indices into ritem.
* src/gram.h (item_index): Introduce it for ritem indices.
* src/closure.h, src/closure.c, src/ielr.c, src/lr0.c,
* src/print-graph.c, src/state.h, src/state.h:
Replace uses of item_number with item_index where appropriate.
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.
Instead of `On Symbols: {b,c,}`, display `On Symbols: b, c`.
* src/counterexample.c (counterexample_report_reduce_reduce): We don't
need braces.
Use commas as a separator, not a terminator.
* tests/counterexample.at: Adjust.
Instead of generating switch statements with numbers, let's use the
symbol kinds. Not only is this more readable, it also makes reading
diff easier, as a change in symbol numbers won't have such a large
effect on the implementation of symbol actions.
* data/skeletons/bison.m4 (_b4_symbol_case): Use the symbol kind
rather than its number.
This should have been done in 3.6, but I wanted to avoid introducing
conflicts into Vincent's work on counterexamples. It turns out it's
completely orthogonal.
* data/README.md, data/skeletons/bison.m4, data/skeletons/c++.m4,
* data/skeletons/c.m4, data/skeletons/glr.c, data/skeletons/java.m4,
* data/skeletons/lalr1.d, data/skeletons/lalr1.java,
* data/skeletons/variant.hh, data/skeletons/yacc.c, src/conflicts.c,
* src/derives.c, src/gram.c, src/gram.h, src/output.c,
* src/parse-gram.c, src/parse-gram.y, src/print-xml.c, src/print.c,
* src/reader.c, src/symtab.c, src/symtab.h, tests/input.at,
* tests/types.at:
s/user_token_number/code/g.
Plus minor changes.
* src/parse_simulation.c: Fix bug in parse_state_free.
Free new_root when simulate_reduction generates zero states.
* src/parse-simulation.c, src/parse-simulation.h
(parse_state_list, parse_state_list_append): New.
* src/parse-simulation.c, src/parse-simulation.h,
* src/counterexample.c: Replace all uses of lists of parse states and
appends to parse_state_lists with the new API.
* src/derivation.h, src/derivation.c: Make derivation struct opaque.
Add derivation_list type for clarity.
(derivation_list_new): New.
(derivation_list_append): New.
(derivation_list_prepend): New.
(derivation_new_leaf): New constructor for derivations with no
children.
* src/counterexample.c, src/parse-simulation.c,
* src/parse-simulation.h: Replace uses of gl_list_t containing
derivations with derivation_list and its API.
Replace calls of dervation_new using null children with
derivation_new_leaf.
* src/parse-simulation.c: replace ps_chunk and its API with typed
versions si_chunk and deriv_chunk.
* src/parse-simlation.h, src/parse-simulation.c: Remove
parse_state_retain_deriv in favor of derivation reference counting.
* src/counterexample.c: Remove search_state_retain_deriv.
