On a case such as
%%
exp
: empty "a"
| "a" empty
empty
: %empty
we used to display
warning: shift/reduce conflict on token "a" [-Wcounterexamples]
Example: • "a"
Shift derivation
exp
↳ 2: • "a" empty
↳ 2: ε
Example: • "a"
Reduce derivation
exp
↳ 1: empty "a"
↳ 3: •
where the shift derivation shows an item "2: empty → ε", with an
explicit "ε", but the reduce derivation shows "3: empty → •", without
"ε".
For consistency, let's always show ε/%empty in rules with an empty
rhs:
Reduce derivation
exp
↳ 1: empty "a"
↳ 3: ε •
* src/derivation.c (derivation_width, derivation_print_tree_impl):
Always show ε/%empty in counterexamples.
* tests/diagnostics.at: Check that case.
* tests/conflicts.at, tests/counterexample.at: Adjust.
* data/skeletons/glr2.cc: Fix some documentation.
Be consistent between class/struct.
(yydoAction, yyresolveAction): Avoid passing yyparser where useless.
This is a fork of glr.cc to be c++-first instead of a wrapper around
glr.c.
* data/skeletons/glr2.cc: New.
* data/skeletons/bison.m4, data/skeletons/c++.m4: Adjust.
* data/skeletons/c.m4 (b4_user_args_no_comma): New.
* src/reader.c (grammar_rule_check_and_complete): glr2.cc is C++.
* tests/actions.at, tests/c++.at, tests/calc.at, tests/conflicts.at,
* tests/input.at, tests/local.at, tests/regression.at, tests/scanner.at,
* tests/synclines.at, tests/types.at: Also check glr2.cc.
Reported by Dennis Clarke.
https://lists.gnu.org/r/bug-bison/2020-08/msg00013.html
* examples/d/local.mk, examples/java/calc/local.mk,
* examples/java/simple/local.mk: Pass bison's options before its
argument, in case we're in POSIX mode.
An assertion failed when the last character is a '\' and we're in a
character or a string.
Reported by Agency for Defense Development.
https://lists.gnu.org/r/bug-bison/2020-08/msg00009.html
* src/scan-gram.l: Catch unterminated escapes.
* tests/input.at (Unexpected end of file): New.
Reported by Agency for Defense Development.
https://lists.gnu.org/r/bug-bison/2020-08/msg00008.html
On an empty such as
%token FOO
BAR
FOO 0
%%
input: %empty
we crash because when we find FOO 0, we decrement ntokens (since FOO
was discovered to be EOF, which is already known to be a token, so we
increment ntokens for it, and need to cancel this). This "works well"
when EOF is properly defined in one go, but here it is first defined
and later only assign token code 0. In the meanwhile BAR was given
the token number that we just decremented.
To fix this, assign symbol numbers after parsing, not during parsing,
so that we also saw all the explicit token codes. To maintain the
current numbers (I'd like to keep no difference in the output, not
just equivalence), we need to make sure the symbols are numbered in
the same order: that of appearance in the source file. So we need the
locations to be correct, which was almost the case, except for nterms
that appeared several times as LHS (i.e., several times as "foo:
..."). Fixing the use of location_of_lhs sufficed (it appears it was
intended for this use, but its implementation was unfinished: it was
always set to "false" only).
* src/symtab.c (symbol_location_as_lhs_set): Update location_of_lhs.
(symbol_code_set): Remove broken hack that decremented ntokens.
(symbol_class_set, dummy_symbol_get): Don't set number, ntokens and
nnterms.
(symbol_check_defined): Do it.
(symbols): Don't count nsyms here.
Actually, don't count nsyms at all: let it be done in...
* src/reader.c (check_and_convert_grammar): here. Define nsyms from
ntokens and nnterms after parsing.
* tests/input.at (EOF redeclared): New.
* examples/c/bistromathic/bistromathic.test: Adjust the traces: in
"%nterm <double> exp %% input: ...", exp used to be numbered before
input.
* cfg.mk (_space_before_paren_exempt): Be less laxist.
* src/output.c, src/reader.c: Fix space before paren issues.
Pacify the warnings where applicable.
Older versions of GCC (4.1.2 here) don't like repeated typedefs.
CC src/bison-parse-simulation.o
src/parse-simulation.c:61: error: redefinition of typedef 'parse_state'
src/parse-simulation.h:74: error: previous declaration of 'parse_state' was here
make: *** [Makefile:7876: src/bison-parse-simulation.o] Error 1
Reported by Nelson H. F. Beebe.
* src/parse-simulation.c (parse_state): Don't typedef,
parse-simulation.h did it already.
This reverts commit d0bec3175f (which
should have read "We have a clash...", not "With have a clash...").
Now that `max()` was renamed `max_int()`, we can use `max` again, as
elsewhere in the code.
* src/counterexample.c (visited_hasher): Alpha reconversion.
Reported by Maarten De Braekeleer.
https://lists.gnu.org/r/bison-patches/2020-07/msg00080.html
We don't want to use gnulib's min and max macros, since we use
function calls in min/max arguments.
* src/location.c (max_int, min_int): Move to...
* src/system.h: here.
* src/counterexample.c, src/derivation.c: Use max_int instead of max.
From
foo.y:1.7-11: error: %type redeclaration for bar
1 | %type <foo> bar bar
| ^~~~~
foo.y:1.7-11: note: previous declaration
1 | %type <foo> bar bar
| ^~~~~
to
foo.y:1.17-19: error: %type redeclaration for bar
1 | %type <foo> bar bar
| ^~~
foo.y:1.13-15: note: previous declaration
1 | %type <foo> bar bar
| ^~~
* src/symlist.h, src/symlist.c (symbol_list_type_set): There's no need
for the tag's location, use that of the symbol.
* src/parse-gram.y: Adjust.
* tests/input.at: Adjust.
We crash if the input contains a string containing a NUL byte.
Reported by Suhwan Song.
https://lists.gnu.org/r/bug-bison/2020-07/msg00051.html
* src/flex-scanner.h (STRING_FREE): Avoid accidental use of
last_string.
* src/scan-gram.l: Don't call STRING_FREE without calling
STRING_FINISH first.
* tests/input.at (Invalid inputs): Check that case.
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.
With have a clash with the "max" function.
src/counterexample.c: In function 'visited_hasher':
src/counterexample.c:720:48: error: declaration of 'max' shadows a global declaration [-Werror=shadow]
src/counterexample.c:116:12: error: shadowed declaration is here [-Werror=shadow]
* src/counterexample.c (visited_hasher): Alpha conversion.
Fix 6b78e50cef, "cex: make "rerun with
'-Wcex'" a note instead of a warning"
* tests/conflicts.at (-W versus %expect and %expect-rr): Fix
expectations.
Adela Vais
Akim Demaille
Valentin Tolmer
Maarten De Braekeleer