Commit Graph

323 Commits

Author SHA1 Message Date
Akim Demaille
f9b360663b glr2.cc: add an example
Currently this example crashes on input such as "T (x) + y;".
The same example with glr.c works properly.

* examples/c++/glr/Makefile, examples/c++/glr/README.md,
* examples/c++/glr/c++-types.test, examples/c++/glr/c++-types.yy,
* examples/c++/glr/local.mk, examples/c++/local.mk: New.
Based on examples/c/glr/c++-types.y.
2020-09-26 18:33:48 +02:00
Adela Vais
f296669c0f d: change the return value of yylex from int to TokenKind
* data/skeletons/lalr1.d: Change the return value.
* examples/d/calc/calc.y, examples/d/simple/calc.y: Adjust.
* tests/scanner.at: Adjust.
* tests/calc.at (_AT_DATA_CALC_Y(d)): New, extracted from...
(_AT_DATA_CALC_Y(c)): here.
The two grammars have been sufficiently different to be separated.
Still trying to be them together results in a maintenance burden.  For
the same reason, instead of specifying the results for D and for the
rest, compute the expected results with D from the regular case.
2020-09-26 08:08:25 +02:00
Akim Demaille
647453a614 examples: add a demonstration of GLR parsers in C
Based on the test case 668 (cxx-type.at:437) "GLR: Merge conflicting
parses, pure, locations".

* examples/c/glr/Makefile, examples/c/glr/README.md,
* examples/c/glr/c++-types.test, examples/c/glr/c++-types.y,
* examples/c/glr/local.mk: New.
2020-09-19 18:05:15 +02:00
Akim Demaille
75c3746ce2 options: rename --defines as --header
The name "defines" is incorrect, the generated file contains far more
than just #defines.

* src/getargs.h, src/getargs.c (-H, --header): New option.
With optional argument, just like --defines, --xml, etc.
(defines_flag): Rename as...
(header_flag): this.
Adjust dependencies.
* data/skeletons/bison.m4, data/skeletons/c.m4, data/skeletons/glr.c,
* data/skeletons/glr.cc, data/skeletons/glr2.cc, data/skeletons/lalr1.cc,
* data/skeletons/yacc.c:
Adjust.
* examples, doc/bison.texi: Adjust.
* tests/headers.at, tests/local.at, tests/output.at: Convert most
tests from using --defines to using --header.
2020-09-19 08:31:49 +02:00
Akim Demaille
93d6a5ba4d examples: d: remove unused token
* examples/d/calc/calc.y, examples/d/simple/calc.y: Remove "=".
2020-09-07 06:46:50 +02:00
Akim Demaille
0d8407440c doc: simplify the extraction of example snippets
* doc/bison.texi: Use qualified paths.
* examples/extexi: Comment changes.
2020-09-05 09:19:39 +02:00
Adela Vais
6e1d83c8a8 examples: d: demonstrate location tracking
* examples/d/calc/calc.y: Track locations.
* examples/d/calc/calc.test: Check locations.
2020-09-03 08:44:42 +02:00
Adela Vais
8032dde383 examples: d: duplicate the example as "simple" and "calc"
* examples/d/Makefile, examples/d/calc.d, examples/d/calc.test,
examples/d/calc/local.mk: Move into...
* examples/d/calc, examples/d/simple: these new directories.
2020-09-03 08:20:41 +02:00
Adela Vais
f3bcb3de0e examples: d: fix the handling of unary +
It was interpreting "+exp" as "-exp".

* examples/d/calc.y: Fix.
* examples/d/calc.test: Check it.
2020-09-02 07:38:42 +02:00
Akim Demaille
067e35a8be build: beware of POSIX mode
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.
2020-08-30 09:38:05 +02:00
Akim Demaille
b7aab2dbad fix: crash when redefining the EOF token
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.
2020-08-07 07:30:06 +02:00
Akim Demaille
dc72b3566d bistromathic: demonstrate caret-diagnostics
* examples/c/bistromathic/parse.y (user_context): We need the current
line.
(yyreport_syntax_error): Quote the guilty line, with squiggles.
* examples/c/bistromathic/bistromathic.test: Adjust.
2020-07-11 18:06:45 +02:00
Akim Demaille
c47e1174d4 bistromathic: do not display parse errors on completion
Currently autocompletion on a line with errors leaks the error
messages.  It can be useful to let the user know, but GNU Readline
does not provide us with an nice way to display the error.  So we
actually break into the current line of the user.

So instead, do not show these errors.

* examples/c/bistromathic/parse.y (user_context): New.
Use %param to pass it to the parser and scanner.
Keep quiet when in computing autocompletion.
2020-07-11 18:05:50 +02:00
Akim Demaille
093eeb27e9 bistromathic: don't stupidly reset the location for each token
That quite defeats the whole point of locations...  But anyway, we
should not see these messages at all.

* examples/c/bistromathic/parse.y (expected_tokens): Fix (useless)
location tracking.
2020-07-11 18:05:41 +02:00
Akim Demaille
dab23c4a21 bistromathic: promote yytoken_kind_t
* examples/c/bistromathic/parse.y: Use yytoken_kind_t rather than int.
2020-07-11 18:05:35 +02:00
Akim Demaille
70fb574717 examples: add license headers
Prompted by Rici Lake.
https://stackoverflow.com/questions/62658368/#comment110853985_62661621
Discussed with Paul Eggert.

* doc/bison.texi, examples/c/bistromathic/parse.y,
* examples/c/lexcalc/parse.y, examples/c/lexcalc/scan.l,
* examples/c/pushcalc/calc.y, examples/c/reccalc/parse.y,
* examples/c/reccalc/scan.l, examples/d/calc.y,
* examples/java/calc/Calc.y, examples/java/simple/Calc.y:
Install the GPL3+ header.
2020-07-08 22:19:37 +02:00
Akim Demaille
964fb2aa6f examples: include the generated header
* examples/c/bistromathic/parse.y, examples/c/lexcalc/parse.y,
* examples/c/reccalc/parse.y: here.
Add some comments.

* src/parse-gram.y (api_version): Pull out of handle_require.
Bump to 3.7.
2020-07-05 08:18:51 +02:00
Akim Demaille
d309bd9f9f package: fix syntax-check errors
* examples/c/bistromathic/bistromathic.test, po/POTFILES.in: here.
2020-07-04 12:10:15 +02:00
Akim Demaille
330552ea49 yacc.c: push: don't clear the parser state when accepting/rejecting
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.
2020-06-29 19:36:41 +02:00
Akim Demaille
7c609859ee bistromathic: don't display undefined locations
Currently, completion when there is a syntax error shows broken
locations.

* examples/c/bistromathic/parse.y (expected_tokens): Initialize the
location.
* examples/c/bistromathic/bistromathic.test: Check that.
2020-06-29 19:10:05 +02:00
Akim Demaille
b1327c56f7 examples: fix missing includes
* examples/c/bistromathic/parse.y: Use abort rather than assert so
that the "unused result" warning is silenced even with -DNDEBUG.
2020-06-06 07:37:20 +02:00
Akim Demaille
7e16bd2cae Merge maint into HEAD
* 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
2020-06-03 08:12:10 +02:00
Akim Demaille
52ce2a008b build: check -Wmissing-prototypes
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=25509
https://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.
2020-06-01 08:29:53 +02:00
Akim Demaille
12f4091de4 tests: show logs
* examples/c/bistromathic/bistromathic.test, examples/test: here.
2020-05-23 18:02:44 +02:00
Akim Demaille
8e70880af1 tests: show logs
* examples/c/bistromathic/bistromathic.test, examples/test: here.
2020-05-23 13:47:31 +02:00
Akim Demaille
4619b32dc0 examples: don't promote unchecked function calls
* 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.
2020-05-16 14:39:57 +02:00
Akim Demaille
f4495da337 examples: use markdown hyperlinks
* examples/c++/README.md, examples/c++/calc++/README.md,
* examples/c/README.md: here.
2020-05-14 07:26:55 +02:00
Akim Demaille
acba58ac59 Merge branch maint
* maint:
  news: update
  maint: post-release administrivia
  version 3.6.1
  c++: style: reorder generated code
  c++: provide yy::parser::symbol_type::name
  c++: make parser::symbol_name public
  examples: beware of ~/.inputrc
  build: also provide lzip compressed tarballs
  style: minor fixes
  yacc.c: restore ansi-c compatibility
2020-05-10 17:33:12 +02:00
Akim Demaille
11b5bac7bf examples: use markdown hyperlinks
* examples/c++/README.md, examples/c++/calc++/README.md,
* examples/c/README.md: here.
2020-05-10 11:51:17 +02:00
Akim Demaille
c3585f41ef examples: beware of ~/.inputrc
* examples/c/bistromathic/bistromathic.test: here.
2020-05-10 09:40:07 +02:00
Akim Demaille
2b63c54f5a style: minor fixes
* examples/c/README.md: here.
2020-05-10 08:03:30 +02:00
Akim Demaille
2ab4058de0 style: minor fixes
* examples/c/README.md: here.
2020-05-09 16:43:59 +02:00
Akim Demaille
d26d10ad6c examples: beware of portability issue on Windows
Reported by Jannick.
https://lists.gnu.org/r/bug-bison/2020-05/msg00040.html
https://lists.gnu.org/r/bug-bison/2020-05/msg00066.html

* examples/test (diff_opts): Use --strip-trailing-cr if supported, to
avoid \n vs. \r\n issues.
* examples/c/bistromathic/bistromathic.test: When on MSYS, don't try
to check autocompletion.
2020-05-08 09:45:29 +02:00
Akim Demaille
d9a9b054ae all: fix the interface of yyexpected_tokens
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.
2020-05-06 08:11:52 +02:00
Akim Demaille
cb9f4cb543 examples: fix handling of syntax errors
The shell grammar does not allow empty statements in then/else part of
an if, but examples/test failed to catch the syntax errors from the
script it ran.  So exited with success anyway.

You would expect 'set -e' to suffice, but with bash 3.2 actually it
does not.  As a matter of fact, I could find a way to have this behave
properly:

    $ cat test.sh
    set -e
    cleanup ()
    {
      status=$?
      echo "cleanup: $status"
      exit $status
    }
    trap cleanup 0 1 2 13 15
    . $1
    s=$?
    echo "test.sh: $s"
    exit $s

    $ cat bistro.test
    if true; then
    fi

    $ /bin/sh ./test.sh ./bistro.test
    ./bistro.test: line 2: syntax error near unexpected token `fi'
    cleanup: 0
    $ echo $?
    0

Remove the set -e (or the trap), and tada, it works...  So we have to
deal with the error by hand.

* examples/test ($exit): Replace with...
($status): this.
Preserve the exit status of the test case.
* examples/c/bistromathic/bistromathic.test: Fix syntax error.
2020-05-05 08:21:12 +02:00
Akim Demaille
ce27796b74 examples: beware of strnlen portability issues
One function missing on Solaris 10 Sparc:

     CCLD     examples/c/bistromathic/bistromathic
    Undefined                       first referenced
    symbol                             in file
    strnlen                             examples/c/bistromathic/bistromathic-parse.o
    ld: fatal: symbol referencing errors. No output written to examples/c/bistromathic/bistromathic

Reported by Dagobert Michelsen.
https://lists.gnu.org/r/bug-bison/2020-05/msg00048.html

* examples/c/bistromathic/parse.y (xstrndup): Don't use strnlen.
xstrndup is assembled from gnulib's xstrndup, strndup and strnlen...
2020-05-04 06:48:00 +02:00
Akim Demaille
6135fdc152 examples: beware of portability issues with sh's trap
On AIX 7.2, when invoking "exit 77", we actually exit with 127.  The
"cleanup" function, called via trap, received an incorrect exit
status, something described in Autoconf's doc.
Reported by Bruno Haible.
https://lists.gnu.org/archive/html/bug-bison/2020-05/msg00029.html
https://lists.gnu.org/archive/html/bug-bison/2020-05/msg00047.html

* examples/test (skip): New.
* examples/c/bistromathic/bistromathic.test,
* examples/c/reccalc/reccalc.test: Use it, to ensure $? is set to 77
when the trap is called.
2020-05-04 06:48:00 +02:00
Akim Demaille
38a8287813 bistromathic: beware of portability issues of readline on AIX
Readline may emit escape sequences before the prompt.
Reported by Bruno Haible.
https://lists.gnu.org/r/platform-testers/2020-05/msg00001.html.

* examples/c/bistromathic/bistromathic.test: Trust readline _only_ if
we get what we expect on some reference computation.
2020-05-03 18:10:58 +02:00
Akim Demaille
df752784c2 examples: beware of portability issues with cmp
As someone wrote nearly 20 years ago in Autoconf's documentation,
don't use cmp to compare text files, but diff.
https://git.savannah.gnu.org/cgit/autoconf.git/commit/?id=abad4f0576a7dc361e5385e19c7681449103cdb1
Reported by Jannick.

* examples/test: Use diff, not cmp.
2020-05-03 17:53:47 +02:00
Akim Demaille
292409e91e build: fix warnings (shown on IRIX)
Appearing on IRIX with gcc -mabi=n32.
Reported by Bruno Haible.
https://lists.gnu.org/r/bug-bison/2020-05/msg00039.html

* examples/c++/variant-11.yy, examples/c/bistromathic/parse.y: Don't
give chars to isdigit, cast them to unsigned char before.
* src/complain.c: Use c_isdigit.
* src/fixits.c (fixits_run): Avoid casts.
* src/lalr.c (goto_print): Use %zu for a size_t.
2020-05-03 17:37:34 +02:00
Akim Demaille
6e2de439e6 bistromathic: beware of portability issues with strndup
Reported by Dagobert Michelsen.
https://lists.gnu.org/r/bug-bison/2020-05/msg00026.html

* examples/c/bistromathic/parse.y (xstrndup): New.
Use it.
2020-05-03 17:06:13 +02:00
Akim Demaille
160df220b1 bistromathic: beware of portability of readline
Don't try to build bistromathic if we don't have readline.
Reported by Bruno Haible.
https://lists.gnu.org/r/bug-bison/2020-05/msg00028.html

* configure.ac (ENABLE_BISTROMATHIC): New.
* examples/c/bistromathic/local.mk: Use it.
* examples/c/bistromathic/bistromathic.test: Exit 77 for skip.
2020-05-03 16:38:34 +02:00
Akim Demaille
da5c072a62 tests: beware of portability issues of sh
"foo || bar" does not invoke bar on AIX 7.2 when foo does not exist.
It just dies.
Reported by Bruno Haible.
https://lists.gnu.org/r/bug-bison/2020-05/msg00029.html

* examples/c/reccalc/reccalc.test: Check for seq in a subshell.
2020-05-03 16:38:34 +02:00
Akim Demaille
13a1537dba java: demonstrate push parsers
* 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.
2020-05-03 11:28:36 +02:00
Akim Demaille
c9b5b68c73 examples: beware of intl portability issues
Reported by Horst von Brand.
https://lists.gnu.org/r/bug-bison/2020-04/msg00033.html

* examples/c/bistromathic/Makefile: libintl might not be needed, but
libm probably is.
* examples/c/bistromathic/parse.y: Include locale.h.
2020-05-03 10:32:33 +02:00
Akim Demaille
26aef31552 examples: beware of portability issues with readline
On OpenBSD 6.5, the prompt is repeated, but not the actual command
line...  Don't try to cope with that.
Reported by Bruno Haible.
https://lists.gnu.org/r/bug-bison/2020-05/msg00015.html

* examples/c/bistromathic/bistromathic.test: Skip when readline behave
this way.
2020-05-03 10:32:33 +02:00
Akim Demaille
392f3caef6 examples: beware of the portability of flex --header-file
The option --header was introduced in version 2.5.6.
The option --header-file was introduced in version 2.6.4.
Reported by Bruno Haible.
https://lists.gnu.org/r/bug-bison/2020-05/msg00013.html

So use --header, and do bother with versions that don't support it.

* m4/flex.m4: Check whether flex supports --header.
* configure.ac (FLEX_WORKS, FLEX_CXX_WORKS): Set to false if it doesn't.
* * examples/c/reccalc/local.mk, examples/c/reccalc/Makefile:
Use --header rather than --header-file.
2020-05-03 10:32:32 +02:00
Akim Demaille
0407acbc59 java: comment changes
* data/skeletons/lalr1.java, examples/java/calc/Calc.y: here.
2020-05-01 10:36:05 +02:00
Akim Demaille
99efa35369 doc: document YYEOF, YYUNDEF and YYerror
* doc/bison.texi (Special Tokens): New.
* examples/c/bistromathic/parse.y: Formatting changes.
2020-04-29 08:23:55 +02:00
Akim Demaille
4c641c5189 tests: beware of portability of readline
* examples/test: here.
2020-04-29 07:01:22 +02:00