A rule is a useless chain iff it's a chain (aka unit, or injection)
rule (i.e., the RHS has length 1), and it's useless (it has no used
defined semantic action).
* src/gram.h, src/gram.c (rule_useless_chain_p): New.
(grammar_dump): Report useless chain rules.
* tests/sets.at: Check the traces.
There are several places where we need to recover the rule from an
item, let's factor that into item_rule. We also want to print items
in a nice way: we do it when generating the *output file, but it is
also useful in debug messages.
* src/gram.h, src/gram.c (item_rule, item_print): New.
* src/print.c (print_core): Use them.
* src/state.h, src/state.c: Propagate constness.
* src/gram.c (grammar_dump): Print the effective number first instead
of last. And fix it (remove the incorrect "+1").
Use t/f for Booleans.
* src/reduce.c: When asked, always print the reduced grammar, even if
there was nothing useless.
* tests/sets.at (Reduced Grammar): Check that.
The files stack.hh and position.hh are deprecated. Rather than
devoting specify %define variables to discard them (api.position.file
and api.stack.file), and rather than having to use special rules when
api.location.file is used, let's simply decide that from %require
"3.2" onwards, these files will not be generated.
The only noticeable thing here is that, in order to be able to check
the behavior of %require "3.2", to have this version (which is still
3.1-*) to accept %require "3.2".
* src/gram.h, src/gram.c (required_version): New.
* src/parse-gram.y (version_check): Set it.
* src/output.c (prepare): Pass it m4.
* data/bison.m4 (b4_required_version_if): Receive it and use it.
* data/location.cc, data/stack.hh: Replace the api.*.file with only
required version comparison.
* tests/input.at: No longer check api.stack.file and api.position.file.
* NEWS, doc/bison.texi: Don't mention them.
Document the %require 3.2 behavior.
* tests/output.at: Use %require 3.2 instead.
In the following grammar, the 'exp' nonterminal is trivially useless.
So, of course, its rules are useless too.
%%
input: '0' | exp
exp: exp '+' exp | exp '-' exp | '(' exp ')'
Previously all the useless rules were reported, including those whose
left-hand side is the 'exp' nonterminal:
warning: 1 nonterminal useless in grammar [-Wother]
warning: 4 rules useless in grammar [-Wother]
2.14-16: warning: nonterminal useless in grammar: exp [-Wother]
input: '0' | exp
^^^
2.14-16: warning: rule useless in grammar [-Wother]
input: '0' | exp
^^^
! 3.6-16: warning: rule useless in grammar [-Wother]
! exp: exp '+' exp | exp '-' exp | '(' exp ')'
! ^^^^^^^^^^^
! 3.20-30: warning: rule useless in grammar [-Wother]
! exp: exp '+' exp | exp '-' exp | '(' exp ')'
! ^^^^^^^^^^^
! 3.34-44: warning: rule useless in grammar [-Wother]
! exp: exp '+' exp | exp '-' exp | '(' exp ')'
! ^^^^^^^^^^^
The interest of being so verbose is dubious. I suspect most of the
time nonterminals are not expected to be useless, so the user wants to
fix the nonterminal, not remove its rules. And even if the user
wanted to get rid of its rules, the position of these rules probably
does not help more that just having the name of the nonterminal.
This commit discard these messages, marked with '!', and keep the
others. In particular, we still report:
2.14-16: warning: rule useless in grammar [-Wother]
input: '0' | exp
^^^
All the useless rules (including the '!' ones) are still reported in
the reports (xml, text, etc.); only the diagnostics on stderr change.
* src/gram.c (grammar_rules_useless_report): Don't complain about
useless rules whose lhs is useless.
* src/reduce.h, src/reduce.c (reduce_nonterminal_useless_in_grammar):
Take a sym_content as argument.
Adjust callers.
* tests/reduce.at (Useless Rules, Underivable Rules, Reduced Automaton):
Adjust.
* origin/maint:
build: don't try to generate docs when cross-compiling
package: fix a reporter's name
%union: fix the support for named %union
package: bump to 2015
flex: don't trust YY_USER_INIT
yacc.c: fix broken union when api.value.type=union and %defines are used
doc: fix missing xref
gnulib: update
location: remove some ugly debugging code traces
build: use abort to pacify compiler errors
package: bump to 2014
doc: specify documentation encoding
Rather than having duplicate info in the symbol and the alias that has
to be resolved later on, both the symbol and the alias have a common
pointer to a separate structure containing this info.
* src/symtab.h (sym_content): New structure.
* src/symtab.c (sym_content_new, sym_content_free, symbol_free): New
* src/AnnotationList.c, src/conflicts.c, src/gram.c, src/gram.h,
* src/graphviz.c, src/ielr.c, src/output.c, src/parse-gram.y, src/print.c
* src/print-xml.c, src/print_graph.c, src/reader.c, src/reduce.c,
* src/state.h, src/symlist.c, src/symtab.c, src/symtab.h, src/tables.c:
Adjust.
* tests/input.at: Fix expectations (order changes).
* src/gram.c (grammar_rules_useless_report): Let -fcaret handle the
pretty-printing of the guilty rules.
(rule_print): Inline in its only use.
* tests/conflicts.at, tests/existing.at, tests/reduce.at,
* tests/regression.at: Adjust.
* NEWS: Document.
* src/gram.c (print_lhs): Use %*s to indent.
* src/print_graph.c (print_lhs): Use obstack_printf.
Became simple enough to be inlined in...
(print_core): here.
Use a "rule*" instead of an index in "rules[]".
* origin/maint:
misc: pacify the Tiny C Compiler
cpp: make the check of Flex version portable
misc: require getline
c++: support wide strings for file names
doc: document carets
tests: enhance existing tests with carets
errors: show carets
getargs: add support for --flags/-f
Conflicts:
doc/bison.texi
m4/.gitignore
src/complain.c
src/flex-scanner.h
src/getargs.c
src/getargs.h
src/gram.c
src/main.c
tests/headers.at
Forthcoming changes will use the warning categories much more often,
so shortening them will improve readability.
* src/complain.c, src/complain.h, src/conflicts.c,
* src/getargs.c, src/getargs.h, src/gram.c (enum warnings):
s/warnings_/W/g.
This change was made by applying emacs' untabify function to
nearly all files in Bison's repository. Required tabs in make
files, ChangeLog, regexps, and test code were manually skipped.
Other notable exceptions and changes are listed below.
* bootstrap: Skip because we sync this with gnulib.
* data/m4sugar/foreach.m4
* data/m4sugar/m4sugar.m4: Skip because we sync these with
Autoconf.
* djgpp: Skip because I don't know how to test djgpp properly, and
this code appears to be unmaintained anyway.
* README-hacking (Hacking): Specify that tabs should be avoided
where not required.
Reported by George Neuner at
<http://lists.gnu.org/archive/html/bug-bison/2010-08/msg00002.html>.
* NEWS (2.5): Document.
* THANKS (George Neuner): Add.
* doc/bison.texinfo (Bison Options): Document.
* src/complain.c, src/complain.h
(warn_at, warn_at_indent, warn): Suppress warning if -Wno-other.
(midrule_value_at): New warning function, similar to yacc_at in
that it's controlled by its own warning category.
* src/getargs.c (warnings_flag): Initialize to warnings_other.
(warnings_args, warnings_types): Add entry for warnings_other.
(usage): Update.
* src/getargs.h (enum warnings): Add entry for warnings_other.
* src/gram.c (grammar_rules_useless_report): If -Wno-other, then
don't print useless rules.
* src/reader.c (symbol_should_be_used): Rather than adjusting the
return value based on whether midrule value warnings are enabled,
accept a new parameter for telling the caller whether true is
being returned for a potential midrule warning.
(grammar_rule_check): Use midrule_value_at for midrule value
warnings, and continue to use warn_at for all other warnings. Let
them check whether the warnings are enabled.
* tests/local.at (AT_BISON_CHECK): Update documentation.
(AT_BISON_CHECK_NO_XML): Check that -Wnone and --warnings=none
disable all warnings exercised in the test suite.
(cherry picked from commit 8ffd7912e3)
Reported by George Neuner at
<http://lists.gnu.org/archive/html/bug-bison/2010-08/msg00002.html>.
* NEWS (2.5): Document.
* THANKS (George Neuner): Add.
* doc/bison.texinfo (Bison Options): Document.
* src/complain.c, src/complain.h
(warn_at, warn_at_indent, warn): Suppress warning if -Wno-other.
(midrule_value_at): New warning function, similar to yacc_at in
that it's controlled by its own warning category.
* src/getargs.c (warnings_flag): Initialize to warnings_other.
(warnings_args, warnings_types): Add entry for warnings_other.
(usage): Update.
* src/getargs.h (enum warnings): Add entry for warnings_other.
* src/gram.c (grammar_rules_useless_report): If -Wno-other, then
don't print useless rules.
* src/reader.c (symbol_should_be_used): Rather than adjusting the
return value based on whether midrule value warnings are enabled,
accept a new parameter for telling the caller whether true is
being returned for a potential midrule warning.
(grammar_rule_check): Use midrule_value_at for midrule value
warnings, and continue to use warn_at for all other warnings. Let
them check whether the warnings are enabled.
* tests/local.at (AT_BISON_CHECK): Update documentation.
(AT_BISON_CHECK_NO_XML): Check that -Wnone and --warnings=none
disable all warnings exercised in the test suite.
* NEWS (2.4.3): Document fix.
* src/complain.c (error_message): Extend to handle incomplete
error messages so warn and warn_at can be used in more cases.
* src/gram.c (grammar_rules_useless_report): Use warn_at so that
-Werror is always obeyed.
* src/reduce.c (reduce_print): Use warn so that the "warnings
being treated as errors" message is printed consistently before
the first warning message. This makes testing easier.
* tests/local.at (AT_BISON_WERROR_MSG): New macro.
(AT_BISON_CHECK_NO_XML): Extend to check -Werror and
--warnings=error when warnings appear in bison's stderr.
(cherry picked from commit 954474bfa1)
* NEWS (2.4.3): Document fix.
* src/complain.c (error_message): Extend to handle incomplete
error messages so warn and warn_at can be used in more cases.
* src/gram.c (grammar_rules_useless_report): Use warn_at so that
-Werror is always obeyed.
* src/reduce.c (reduce_print): Use warn so that the "warnings
being treated as errors" message is printed consistently before
the first warning message. This makes testing easier.
* tests/local.at (AT_BISON_WERROR_MSG): New macro.
(AT_BISON_CHECK_NO_XML): Extend to check -Werror and
--warnings=error when warnings appear in bison's stderr.
(cherry picked from commit 954474bfa1)
