Avoid duplicate warnings about %error-verbose, once for deprecation,
another for duplicate. Keep only the duplicate warning for the second
occurrence of %error-verbose.
This will help removal fixits.
* src/scan-gram.l (%error-verbose): Return as a PERCENT_ERROR_VERBOSE
token.
* src/parse-gram.y (do_error_verbose): New.
Use it.
* src/muscle-tab.c (muscle_percent_variable_update): Handle pseudo
variables such as %error-verbose.
Currently, on
%define parser_class_name "Parser"
%define parser_class_name "Parser"
%%
exp:;
we issue:
foo.y:1.9-25: warning: deprecated directive, use '%define api.parser.class {Parser}' [-Wdeprecated]
%define parser_class_name "Parser"
^~~~~~~~~~~~~~~~~
foo.y:2.9-25: warning: deprecated directive, use '%define api.parser.class {Parser}' [-Wdeprecated]
%define parser_class_name "Parser"
^~~~~~~~~~~~~~~~~
foo.y:2.9-25: error: %define variable 'api.parser.class' redefined
%define parser_class_name "Parser"
^~~~~~~~~~~~~~~~~
foo.y:1.9-25: previous definition
%define parser_class_name "Parser"
^~~~~~~~~~~~~~~~~
Let's get rid of the second warning about the deprecated variable
parser_class_name. This is noise, but it will also be a problem with
fixits for removing duplicates, as we will first generate the update,
and then it's too late to remove it: fixits do not edit the result of
previous fixits.
So generate this instead:
foo.y:1.1-34: warning: deprecated directive, use '%define api.parser.class {Parser}' [-Wdeprecated]
%define parser_class_name "Parser"
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.y:2.1-34: error: %define variable 'api.parser.class' redefined
%define parser_class_name "Parser"
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.y:1.1-34: previous definition
%define parser_class_name "Parser"
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
* src/muscle-tab.c (muscle_percent_variable_update): Pass the warning
to the caller, instead of issuing it.
(muscle_percent_define_insert): Issue this warning only if we don't
have to complain about a duplicate definition.
* tests/input.at: Adjust expectations.
* src/parse-gram.y: Use the location of the whole definition to record
the location of a %define variable, instead of just the name of the
variable.
Adjust tests.
Introduce proper support for fixits, instead of just printing them on
demand.
* bootstrap.conf: We need gnulib's xlists.
* src/fixits.h, src/fixits.c: New.
* src/complain.c (deprecated_directive): Use fixits_register.
* src/main.c (main): Use fixits_free.
Currently the diagnostics for %name-prefix are not precise enough. In
particular, they does not show that braces must be used instead of
quotes.
Before:
foo.y:3.1-14: warning: deprecated directive, use '%define api.prefix' [-Wdeprecated]
%name-prefix = "foo"
^^^^^^^^^^^^^^
After:
foo.y:3.1-20: warning: deprecated directive, use '%define api.prefix {foo}' [-Wdeprecated]
%name-prefix = "foo"
^^^^^^^^^^^^^^^^^^^^
To do this we need the value passed to %name-prefix, so move the
warning from the scanner to the parser.
Accuracy will be very important for the forthcoming changes.
* src/parse-gram.y (do_name_prefix): New.
(PERCENT_NAME_PREFIX): Have a semantic value: the raw source, with
possibly underscores, equal sign, and spaces. This is used to provide
a more accurate message. It does not take comments into account,
but...
* src/scan-gram.l (%name-prefix): Delegate the warnings to the parser.
* tests/headers.at, tests/input.at: Adjust expectations.
* src/muscle-tab.c (muscle_percent_variable_update): Avoid allocating
memory when it is not needed, which should be most of the time (when
there's no update to perform).
Adjust callers.
This line:
slice<stack_symbol_type, stack_type> slice (yystack_, yylen);
triggers warnings:
parse.h:1790:11: note: shadowed declaration is here
Reported by Frank Heckenbach.
http://lists.gnu.org/archive/html/bug-bison/2019-01/msg00002.html
* configure.ac (warn_c): Move -Wshadow to...
(warn_common): here.
* data/skeletons/stack.hh (slice): Define as an inner class of stack.
* data/skeletons/lalr1.cc: Adjust.
Rename the variable as 'range' instead of 'slice'.
There are many macros that are defined and used just
once (b4_public_if, b4_abstract_if, etc.). That's overkill. Rather,
let's define a macro to build the "public class YYParser" line.
It appears that the same syntax with "extends", "abstract", etc. is
implemented in the D parser, which looks very fishy...
* data/skeletons/d.m4, data/skeletons/java.m4 (b4_public_if)
(b4_abstract_if, b4_final_if, b4_strictfp_if): Replace with
(b4_parser_class_declaration): this.
* data/skeletons/lalr1.d, data/skeletons/lalr1.java: Adjust.
Commit 90a8537e62 was right, but issued
two error messages. Commit 80ef7e7639
tried to address that by mapping yychar and yytoken to empty, but that
completely breaks the invariants of glr.c. In particular, yygetToken
can be called repeatedly and is expected to return the latest result,
unless yytoken is YYEMPTY. Since the previous attempt was "recording"
that the token was coming from an exception by setting it to YYEMPTY,
instead of getting again the faulty token, we fetched another one.
Rather, revert to the first approach: map yytoken to "invalid token",
but record in yychar the fact that we come from an exception thrown in
the scanner.
* data/skeletons/glr.c (YYFAULTYTOK): New.
(yygetToken): Use it to record syntax errors from the scanner.
* tests/c++.at (Syntax error as exception): In addition to checking
syntax_error with error recovery, make sure it also behaves as
expected without.
The previous name was historical and inconsistent.
* src/muscle-tab.c (define_directive): Use the proper value passing
syntax, based on the muscle kind.
(muscle_percent_variable_update): Use the right value passing syntax.
Migrate from parser_class_name to api.parser.class.
* data/skeletons: Migrate from parser_class_name to api.parser.class.
* doc/bison.texi (%define Summary): Document both parser_class_name
and api.parser.class.
Promote the latter over the former.
This is very debatable. This function is not pure at all, so it could
stick to returning void: that's a common coding style to tell the
difference between "real" (pure) functions and side-effecting
subroutines. However, we already have this style elsewhere (e.g.,
yylex), and I feel the callers are somewhat nice to read this way.
* data/skeletons/glr.c (yygetLRActions): Return the action rather than
passing by pointer.
While at it, fix type of yytoken.
Adjust callers.
Reported by Askar Safin.
https://lists.gnu.org/archive/html/bison-patches/2019-01/msg00000.html
* data/skeletons/glr.c (yygetToken): Return YYEMPTY when an exception
is thrown.
* data/skeletons/lalr1.cc: Log when an exception is caught.
* tests/c++.at (Syntax error as exception): Be sure to recover from
error before triggering another error.
This way, it is easier to make sure its implementation is available in
glr.cc too, which is not the case currently.
* data/skeletons/c++.m4 (b4_public_types_define): Move the
implementation of syntax_error...
(b4_public_types_declare): here.
* tests/local.at (AT_LOCATION_TYPE_IF): Turn into...
(AT_LOCATION_TYPE_SPAN_IF): this.
Adjust dependencies.
* tests/headers.at (Several parsers): Add another C++ parser,
which uses the first C++ parser's locations.
We used to create a short definition of yy::parser with all the
implementations of its member functions outside. But yy::parser is no
longer short and simple to read. Maintaining each function twice is
painful: a lot of redundancy but different indentation levels, output
which depends on whether we are in a header or not (see
d132c2d545), etc.
Let's simplify this and put the implementations into the class
definition itself.
Discussed in this monologue:
https://lists.gnu.org/archive/html/bison-patches/2018-12/msg00058.html.
* data/skeletons/c++.m4, data/skeletons/lalr1.cc,
* data/skeletons/variant.hh (b4_basic_symbol_constructor_define)
(_b4_token_constructor_declare, b4_token_constructor_declare)
Merge into...
(b4_basic_symbol_constructor_define, _b4_token_constructor_define)
(b4_token_constructor_define): these.
Commit 112ccb5ed7 moved the skeletons
from dist_pkgdata_DATA to dist_skeletons_DATA, hence broke the dependencies.
* Makefile.am (dependencies): New.
Use it where appropriate.
We used to define such auxiliary structures outside the class, mainly
as a matter of style to keep the definition of yy::parser short and
simple. However, now there's a lot more code generated inside the
class definition (e.g., all the token constructors), so the
readability no longer applies.
However, if we move stack (and slice) inside yy::parser, then it
should no longer be needed to change the namespace to have multiple
parsers: changing the class name should suffice.
One common argument against inner classes is that they code bloat. It
hardly applies here, since typically different parsers will have
different semantic value types, hence different actual stack types.
* data/skeletons/lalr1.cc: Invoke b4_stack_define inside yy::parser.
Suggested by David Barto
https://lists.gnu.org/archive/html/help-bison/2015-02/msg00004.html
and Victor Zverovich.
https://lists.gnu.org/archive/html/bison-patches/2018-10/msg00121.html
This is very easy to do, thanks to work by Bruno Haible in gnulib.
See "Supporting Relocation" in gnulib's documentation.
* bootstrap.conf: We need relocatable-prog and relocatable-script (for yacc).
* src/yacc.in: New.
* configure.ac, src/local.mk: Instantiate it.
* src/main.c, src/output.c (main, pkgdatadir): Use relocatable2.
* doc/bison.texi (FAQ): Document it.
Suggested by Wolfgang Thaller.
http://lists.gnu.org/archive/html/bug-bison/2018-12/msg00081.html
* data/c++.m4 (basic_symbol, by_type): Instead of provide either move
or copy constructor, always provide the copy one.
* tests/c++.at (C++ Variant-based Symbols Unit Tests): Check it.
Currently the following piece of code crashes (with parse.assert),
because we don't record that s was moved-from, and we invoke its dtor.
{
auto s = parser::make_INT (42);
auto s2 = std::move (s);
}
Reported by Wolfgang Thaller.
http://lists.gnu.org/archive/html/bug-bison/2018-12/msg00077.html
* data/c++.m4 (by_type): Provide a move-ctor.
(basic_symbol): Be sure not to read a moved-from value.
* tests/c++.at (C++ Variant-based Symbols Unit Tests): Check this case.
* tests/c++.at: Use AT_YYLEX_PROTOTYPE etc.
Which requires that we use the same argument names (lvalp, etc.).
* tests/local.at (AT_NAME_PREFIX): Fix regex.
Instead of introducing make_symbol (whose name, btw, somewhat
infringes on the user's "name space", if she defines a token named
"symbol"), let's make the construction of symbol_type safer, using
assertions.
For instance with:
%token ':' <std::string> ID <int> INT;
generate:
symbol_type (int token, const std::string&);
symbol_type (int token, const int&);
symbol_type (int token);
It does mean that now named token constructors (make_ID, make_INT,
etc.) go through a useless assert, but I think we can ignore this: I
assume any decent compiler will inline the symbol_type ctor inside the
make_TOKEN functions, which will show that the assert is trivially
verified, hence I expect no code will be emitted for it. And anyway,
that's an assert, NDEBUG controls it.
* data/c++.m4 (symbol_type): Turn into a subclass of
basic_symbol<by_type>.
Declare symbol constructors when variants are enabled.
* data/variant.hh (_b4_type_constructor_declare)
(_b4_type_constructor_define): Replace with...
(_b4_symbol_constructor_declare, _b4_symbol_constructor_def): these.
Generate symbol_type constructors.
* doc/bison.texi (Complete Symbols): Document.
* tests/types.at: Check.
On
%token <int> FOO BAR
we currently generate make_FOO(int) and make_BAR(int). However, in
order to factor their scanners, some users would also like to have
make_symbol(tok, int), where tok is FOO or BAR. To ensure type
safety, add assertions that do check that value type and token type
match. Bind this assertion to the parse.assert %define variable.
Suggested by Frank Heckenbach.
http://lists.gnu.org/archive/html/bug-bison/2018-12/msg00034.html
Should also match expectations from Аскар Сафин.
http://lists.gnu.org/archive/html/bug-bison/2018-12/msg00023.html
* data/variant.hh: Use b4_token_visible_if where applicable.
(_b4_type_constructor_declare, _b4_type_constructor_define): New.
Use them.
Bitten by macros, again.
See 680b715518.
* data/variant.hh (_b4_symbol_constructor_declare)
(_b4_symbol_constructor_define): Do not use user types, which can
include commas as in `std::pair<int, int>`, to macros.
* tests/local.at: Adjust the lex related macros to support the
case of token constructors.
* tests/types.at: Also check token constructors on types with commas.
Prompted by Rici Lake.
http://lists.gnu.org/archive/html/bug-bison/2018-10/msg00000.html
We have four classes of directives that declare symbols: %nterm,
%type, %token, and the family of %left etc. Currently not all of them
support the possibility to have several type tags (`<type>`), and not
all of them support the fact of not having any type tag at all
(%type). Let's unify this.
- %type
POSIX Yacc specifies that %type is for nonterminals only. However,
some Bison users want to use it for both tokens and nterms
(actually, Bison's own grammar does this in several places, e.g.,
CHAR). So it should accept char/string literals.
As a consequence cannot be used to declare tokens with their alias:
`%type foo "foo"` would be ambiguous (are we defining foo = "foo",
or are these two different symbols?)
POSIX specifies that it is OK to use %type without a type tag. I'm
not sure what it means, but we support it.
- %token
Accept token declarations with number and string literal:
(ID|CHAR) NUM? STRING?.
- %left, etc.
They cannot be the same as %token, because we accept to declare the
symbol with %token, and to then qualify its precedence with %left.
Then `%left foo "foo"` would also be ambiguous: foo="foo", or two
symbols.
They cannot be simply a list of identifiers, but POSIX Yacc says we
can declare token numbers here. I personally think this is a bad
idea, precedence management is tricky in itself and should not be
cluttered with token declaration issues.
We used to accept declaring a token number on a string literal here
(e.g., `%left "token" 1`). This is abnormal. Either the feature is
useful, and then it should be supported in %token, or it's useless
and we should not support it in corner cases.
- %nterm
Obviously cannot accept tokens, nor char/string literals. Does not
exist in POSIX Yacc, but since %type also works for terminals, it is
a nice option to have.
* src/parse-gram.y: Avoid relying on side effects. For instance, get
rid of current_type, rather, build the list of symbols and iterate
over it to assign the type.
It's not always possible/convenient. For instance, we still use
current_class.
Prefer "decl" to "def", since in the rest of the implementation we
actually "declare" symbols, we don't "define" them.
(token_decls, token_decls_for_prec, symbol_decls, nterm_decls): New.
Use them for %token, %left, %type and %nterm.
* src/symlist.h, src/symlist.c (symbol_list_type_set): New.
* tests/regression.at b/tests/regression.at
(Token number in precedence declaration): We no longer accept
to give a number to string literals.
After having spent quite some time on cleaning the handling of symbol
declarations in the grammar files, I believe we should keep it.
It looks like it's a duplicate of %type, but it is not. While POSIX
Yacc requires %type to apply only to nonterminal symbols, it appears
that both byacc and bison accept it for tokens too. And some
experienced users do actually expect this feature to group
symbols (terminal or not) by type ("On the other hand, it is generally
more useful IMHO to group terminals and non-terminals with the same
type tag together",
http://lists.gnu.org/archive/html/bug-bison/2018-10/msg00000.html).
Even Bison's own parser does this today (see CHAR).
Basically reverts 7928c3e6fb.
* src/scan-gram.l (%nterm): Dedeprecate, but issue a Wyacc warning.
* tests/input.at: Adjust expectations.
(Yacc warnings on symbols): New.
* src/symtab.c (symbol_class_set): Fix error introduced in
20b0746793.
I personally prefer 'non terminal', or 'non-terminal', but
'nonterminal' is the common spelling.
* data/glr.c, src/parse-gram.y, src/symtab.c, src/symtab.h,
* tests/input.at, doc/refcard.tex: here.
Currently our error messages include both "symbol redeclared" and
"symbol redefined", and they mean something different. This is
obscure, let's make this clearer.
I think the idea between 'definition' vs. 'declaration' is that in the
case of the nonterminals, the actual definition is its set of rules,
so %nterm would be about declaration. The case of %token is less
clear.
* src/symtab.c (complain_class_redefined): New.
(symbol_class_set): Use it.
Simplify the logic of this function to clearly skip its body when the
preconditions are not met.
* tests/input.at (Symbol class redefinition): New.
Convert some of the READMEs to Markdown, which is now more common, and
nicely displayed in some git hosting services.
Add missing READMEs and Makefiles. Generate XML, HTML and Dot files. Be
sure to ship the test files. Complete CLEANFILES to remove all generated
files.
* examples/calc++: Move into...
* examples/c++: here.
* examples/mfcalc, examples/rpcalc: Move into...
* examples/c: here.
* examples/README.md, examples/c++/calc++/Makefile, examples/c/local.mk,
* examples/c/mfcalc/Makefile, examples/c/rpcalc/Makefile,
* examples/d/README.md, examples/java/README.md:
New files.
* examples/test (medir): Be robust to deeper directory nesting.
Revamping the handling of the symbols is the grammar is much more
delicate than I anticipated. Let's first move things around for
clarity.
* src/symtab.c (symbol_make_alias): Don't accept to alias
non-terminals.
(symbol_user_token_number_set): Don't accept user token numbers
for non-terminals.
Don't do anything in case of redefinition, instead of trying to
update. The flow is eaier to follow this way.
Akim Demaille