<http://lists.gnu.org/archive/html/bug-bison/2006-09/msg00018.html>.
* src/parse-gram.y (symbol_declaration): Don't put statements
before declarations; it's not portable to C89.
* src/scan-code.l (handle_action_at): Likewise.
* src/scan-code.l: Always initialize braces_level; the old code
left it uninitialized and therefore had undefined behavior.
Don't attempt to redefine 'assert', since it runs afoul of
systems where standard headers (mistakenly) include <assert.h>.
Instead, define and use our own alternative, called 'aver'.
* src/reader.c: Don't include assert.h, since we no longer
use assert.
* src/scan-code.l: Likewise.
* src/system.h (assert): Remove, replacing with....
(aver): New function, taking a bool arg. All uses changed.
* src/tables.c (pack_vector): Ensure that aver arg is bool,
not merely an integer.
%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.
* src/flex-scanner.h (FLEX_NO_OBSTACK): New macro that blocks obstack
definitions so gcc won't warn when obstack_for_string is unused.
* src/scan-code.l: config.h and system.h are already #include'd by
scan-code-c.c, so get rid of them here.
* src/scan-gram.l: Likewise.
* src/scan-skel.l: Likewise, and use flex-scanner.h without obstack
definitions rather than duplicating the rest of it.
* src/scan-gram-c.c, scan-skel-c.c: #include "system.h".
* src/scan-code.h, src/scan-code.l (translate_action)
(translate_rule_action, translate_symbol_action, translate_code):
Return char *, not const char *.
* src/parse-gram.y (declaration): Rename as...
(prologue_declaration): this.
(string_content): Remove this nonterminal, use STRING.
(braceless, content, content.opt): New nonterminal.
Use them.
(%define): Now accept content.opt, i.e., accept also BRACED_CODE
as value.
* src/scan-gram.l (getargs.h): Don't include it.
YYSTYPE if your grammar contains at least one <type> tag.
Your YYSTYPE need not be a macro; it can be a typedef.
* doc/bison.texinfo (Value Type, Multiple Types, Location Type):
(Union Decl, Decl Summary): Document this.
* data/glr.c (YYSTYPE): Implement this.
* data/glr.cc (YYSTYPE): Likewise.
* data/lalr1.cc (YYSTYPE): Likewise.
* data/yacc.c (YYSTYPE): Likewise.
* src/output.c (prepare): Output tag_seen_flag.
* src/parse-gram.y (declaration, grammar_declaration):
Use 'union_seen' rather than 'typed' to determine whether
%union has been seen, since grammars can now be typed without
%union.
(symbol_declaration, type.opt, symbol_def):
Keep track of whether a tag has been seen.
* src/reader.c (union_seen, tag_seen): New vars.
(typed): remove.
* src/reader.h (union_seen, tag_seen, typed): Likewise.
* src/scan-code.l (untyped_var_seen): New variable.
(handle_action_dollar): Adjust to above changes.
(handle_action_dollar, handle_action_at):
Improve overflow checking for outlandish numbers.
* tests/input.at (AT_CHECK_UNUSED_VALUES): Redo test to
avoid new diagnostics generated by above changes.
* tests/regression.at (YYSTYPE typedef): Add test to check
for type tags without %union.
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.
to be a rule action. Mentioned at
<http://lists.gnu.org/archive/html/bison-patches/2006-06/msg00105.html>.
* src/scan-gram.l: Move midrule action detection from the start of the
scanning of any braced code to...
* src/parse-gram.y (rhs): ... the parsing of braced code as a rule
action. For readability, use $2 and @2 rather than the equivalent
global variables.
* tests/regression.at (Braced code in declaration in rules section):
New test to catch the error fixed by the above patch.
Work on code readability some.
* src/scan-code.l (current_rule): Get rid of this misleading and
redundant declaration: it's actually extern'ed in reader.h.
(YY_DECL, code_lex, handle_action_dollar, handle_action_at,
translate_action): Add a rule argument and use it instead of the global
current_rule.
(translate_rule_action): This already receives current_rule through an
argument, so pass it on to translate_action instead of assigning
current_rule to current_rule.
(translate_symbol_action, translate_code): Pass rule = NULL to
translate_action.
As a consequence, the relation between the grammar scanner and
parser is much simpler. We can also split "composite tokens" back
into simple tokens.
* src/gram.h (ITEM_NUMBER_MAX, RULE_NUMBER_MAX): New.
* src/scan-gram.l (add_column_width, adjust_location): Move to and
rename as...
* src/location.h, src/location.c (add_column_width)
(location_compute): these.
Fix the column count: the initial column is 0.
(location_print): Be robust to ending column being 0.
* src/location.h (boundary_set): New.
* src/main.c: Adjust to scanner_free being renamed as
gram_scanner_free.
* src/output.c: Include scan-code.h.
* src/parse-gram.y: Include scan-gram.h and scan-code.h.
Use boundary_set.
(PERCENT_DESTRUCTOR, PERCENT_PRINTER, PERCENT_INITIAL_ACTION)
(PERCENT_LEX_PARAM, PERCENT_PARSE_PARAM): Remove the {...} part,
which is now, again, a separate token.
Adjust all dependencies.
Whereever actions with $ and @ are used, use translate_code.
(action): Remove this nonterminal which is now useless.
* src/reader.c: Include assert.h, scan-gram.h and scan-code.h.
(grammar_current_rule_action_append): Use translate_code.
(packgram): Bound check ruleno, itemno, and rule_length.
* src/reader.h (gram_in, gram__flex_debug, scanner_cursor)
(last_string, last_braced_code_loc, max_left_semantic_context)
(scanner_initialize, scanner_free, scanner_last_string_free)
(gram_out, gram_lineno, YY_DECL_): Move to...
* src/scan-gram.h: this new file.
(YY_DECL): Rename as...
(GRAM_DECL): this.
* src/scan-code.h, src/scan-code.l, src/scan-code-c.c: New.
* src/scan-gram.l (gram_get_lineno, gram_get_in, gram_get_out):
(gram_get_leng, gram_get_text, gram_set_lineno, gram_set_in):
(gram_set_out, gram_get_debug, gram_set_debug, gram_lex_destroy):
Move these declarations, and...
(obstack_for_string, STRING_GROW, STRING_FINISH, STRING_FREE):
these to...
* src/flex-scanner.h: this new file.
* src/scan-gram.l (rule_length, rule_length_overflow)
(increment_rule_length): Remove.
(last_braced_code_loc): Rename as...
(gram_last_braced_code_loc): this.
Adjust to the changes of the parser.
Move all the handling of $ and @ into...
* src/scan-code.l: here.
* src/scan-gram.l (handle_dollar, handle_at): Remove.
(handle_action_dollar, handle_action_at): Move to...
* src/scan-code.l: here.
* src/Makefile.am (bison_SOURCES): Add flex-scanner.h,
scan-code.h, scan-code-c.c, scan-gram.h.
(EXTRA_bison_SOURCES): Add scan-code.l.
(BUILT_SOURCES): Add scan-code.c.
(yacc): Be robust to white spaces.
* tests/conflicts.at, tests/input.at, tests/reduce.at,
* tests/regression.at: Adjust the column numbers.
* tests/regression.at: Adjust the error message.
