Discussed starting at
<http://lists.gnu.org/archive/html/bison-patches/2006-09/msg00060.html>.
* NEWS (2.3a+): Mention.
* doc/bison.texinfo (Freeing Discarded Symbols): Document this and the
previous change today related to mid-rules.
(Bison Symbols): Remove %symbol-default and add <*> and <!>.
* src/parser-gram.y (PERCENT_SYMBOL_DEFAULT): Remove.
(TYPE_TAG_ANY): Add as <*>.
(TYPE_TAG_NONE): Add as <!>.
(generic_symlist_item): Remove RHS for %symbol-default and add RHS's
for <*> and <!>.
* src/scan-gram.l (PERCENT_SYMBOL_DEFAULT): Remove.
(TYPE_TAG_ANY, TYPE_TAG_NONE): Add.
* src/symlist.c (symbol_list_default_new): Split into tagged and
tagless versions.
(symbol_list_destructor_set, symbol_list_printer_set): Split
SYMLIST_DEFAULT case into SYMLIST_DEFAULT_TAGGED and
SYMLIST_DEFAULT_TAGLESS.
* src/symlist.h: Update symbol_list_default*_new prototypes.
(symbol_list.content_type): Split enum value SYMLIST_DEFAULT into
SYMLIST_DEFAULT_TAGGED and SYMLIST_DEFAULT_TAGLESS.
* src/symtab.c (default_destructor, default_destructor_location,
default_printer, default_printer_location): Split each into tagged and
tagless versions.
(symbol_destructor_get, symbol_destructor_location_get,
symbol_printer_get, symbol_printer_location_get): Implement tagged
default and tagless default cases.
(default_destructor_set, default_printer_set): Split each into tagged
and tagless versions.
* src/symtab.h: Update prototypes.
* tests/actions.at (Default %printer and %destructor): Rename to...
(Default tagless %printer and %destructor): ... this, and extend.
(Per-type %printer and %destructor): Rename to...
(Default tagged and per-type %printer and %destructor): ... this, and
extend.
(Default %printer and %destructor for user-defined end token): Extend.
(Default %printer and %destructor are not for error or $undefined):
Update.
(Default %printer and %destructor are not for $accept): Update.
(Default %printer and %destructor for mid-rule values): Extend.
* tests/input.at (Default %printer and %destructor redeclared): Extend.
(Unused values with default %destructor): Extend.
%symbol-default instead of an empty symbol list, and start working on
new per-type %destructor/%printer. Discussed at
<http://lists.gnu.org/archive/html/bison-patches/2006-09/msg00007.html>.
* NEWS (2.3+): Add %symbol-default to example.
* bison.texinfo (Freeing Discarded Symbols): Likewise.
(Bison Symbols): Add entry for %symbol-default.
* src/parse-gram.y (PERCENT_SYMBOL_DEFAULT): New token.
(generic_symlist, generic_symlist_item): New nonterminals for creating
a list in which each item is a symbol, semantic type, or
%symbol-default.
(grammar_declaration): Use generic_symlist in %destructor and %printer
declarations instead of symbols.1 or an empty list.
(symbol_declaration, precedence_declaration, symbols.1): Update actions
for changes to symbol_list.
* src/reader.c: Update for changes to symbol_list.
* src/scan-code.l: Likewise.
* src/scan-gram.l: Scan new PERCENT_SYMBOL_DEFAULT token.
* src/symlist.c, src/symlist.h: Extend such that a list node may
represent a semantic type or a %symbol-default in addition to just an
ordinary symbol. Add switched functions for setting %destructor's and
%printer's.
* tests/actions.at, tests/input.at: Add %symbol-default to all default
%destructor/%printer declarations.
declared after the %merge.
* src/reader.c (get_merge_function): Don't set the merger type yet.
(record_merge_function_type): New function for setting the merger type
and checking for clashes.
(grammar_current_rule_merge_set): Set the location of the %merge for
the current rule.
(packgram): Invoke record_merge_function_type for each rule now that
all symbol type declarations have been parsed.
* src/reader.h (merger_list.type_declaration_location): New member
storing the location of the first %merge from which the type for this
merging function was derived.
* src/symlist.h (symbol_list.merger_declaration_location): New member
storing the location of a rule's %merge, if any.
* tests/glr-regression.at (Missed %merge type warnings when LHS type is
declared later): New test to catch the error fixed by the above patch.
declarations appear after the rules. Don't mistake the type of $$ in
a midrule to be that of its parent rule's $$.
* src/reader.c (grammar_current_rule_end): Don't invoke
grammar_rule_check yet since not all symbol declarations may have been
parsed yet.
(grammar_midrule_action): Likewise.
Don't record whether the midrule's $$ has been used yet since actions
haven't been translated yet.
Record the midrule's parent rule and its RHS index within the parent
rule.
(grammar_current_rule_action_append): Don't translate the action yet
since not all symbol declarations may have been parsed yet and, thus,
warnings about types for $$, $n, @$, and @n can't be reported yet.
(packgram): Translate the action and invoke grammar_rule_check now that
all symbol declarations have been parsed.
* src/scan-code.l (handle_action_dollar): Now that this is invoked
after parsing the entire grammar file, the symbol list here in the case
of a midrule is actually the midrule's empty RHS, so reference its
parent rule's RHS where necessary.
On the other hand, now that you can already know it's a midrule, you
aren't forced to think $$ has the same type as its parent rule's $$.
(handle_action_at): In the case of a midrule, reference the parent rule
where necessary.
* src/symlist.c (symbol_list_new): Initialize new midrule-related
members.
(symbol_list_length): Now that this is invoked after all rules have
been parsed, a NULL symbol (rather than a NULL symbol list node)
terminates a rule. symbol_list_print already does this correctly.
* src/symlist.h (symbol_list.midrule_parent_rule,
symbol_list.midrule_parent_rhs_index): New members so that midrules can
remember their relationships with their parents.
* tests/input.at (Type Clashes): Extend to catch the midrule $$ error
fixed by the above patch.
(_AT_UNUSED_VALUES_DECLARATIONS, AT_CHECK_UNUSED_VALUES): New m4 macros
implementing...
(Unused values): ... this old test case and...
(Unused values before symbol declarations): ... this new test case.
This one is the same as `Unused values' except that all symbol
declarations appear after the rules in order to catch the rest of the
errors fixed by the above patch.
* src/symlist.h, src/symlist.c (symbol_list): Add a mid_rule
member.
(symbol_list_new): Adjust.
* src/reader.c (symbol_typed_p): New.
(grammar_rule_check): Use it.
(grammar_midrule_action): Bind a mid-rule LHS to its rule.
Check its rule.
* tests/input.at (AT_CHECK_UNUSED_VALUES): New.
Use it.
* tests/actions.at (Exotic Dollars): Adjust.
(STRUNIQ_EQ, struniq_assert, struniq_assert_p): New.
Use struniq for symbols.
* src/symtab.h (symbol_t): The tag member is a struniq.
(symbol_type_set): Adjust.
* src/symtab.c (symbol_new): Takes a struniq.
(symbol_free): Don't free the tag member.
(hash_compare_symbol_t, hash_symbol_t): Rename as...
(hash_compare_symbol, hash_symbol): these.
Use the fact that tags as struniqs.
(symbol_get): Use struniq_new.
* src/symlist.h, src/symlist.c (symbol_list_n_type_name_get):
Returns a strniq.
* src/reader.h (merger_list, grammar_currentmerge_set): The name
and type members are struniqs.
* src/reader.c (get_merge_function)
(grammar_current_rule_merge_set): Adjust.
(TYPE, current_type): Are struniq.
Use struniq for file names.
* src/files.h, src/files.c (infile): Split into...
(grammar_file, current_file): these.
* src/scan-gram.c (YY_USER_INIT, handle_syncline): Adjust.
* src/reduce.c (reduce_print): Likewise.
* src/getargs.c (getargs): Likewise.
* src/complain.h, src/complain.c: Likewise.
* src/main.c (main): Call struniqs_new early enough to use it for
file names.
Don't free the input file name.
* src/scan-gram.l (handle_dollar, handle_at): Compute the
rule_length only when needed.
* src/output.c (actions_output, token_definitions_output): Output
the full M4 block.
* src/symtab.c: Don't access directly to the symbol tag, use
symbol_tag_get.
* src/parse-gram.y: Use symbol_list_free.
