+2006-09-04 Joel E. Denny <jdenny@ces.clemson.edu>
+
+ Require default %destructor/%printer to be declared using
+ %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.
+
+2006-08-23 Joel E. Denny <jdenny@ces.clemson.edu>
+
+ Whether the default %destructor/%printer applies to a particular symbol
+ isn't a question of whether the user *declares* that symbol (in %token,
+ for example). It's a question of whether the user by any means
+ *defines* the symbol at all (by simply using a char token, for
+ example). $end is defined by Bison whereas any other token with token
+ number 0 is defined by the user. The error token is always defined by
+ Bison regardless of whether the user declares it with %token, but we
+ may one day let the user define error as a nonterminal instead.
+ * NEWS (2.3+): Say "user-defined" instead of "user-declared".
+ * doc/bison.texinfo (Freeing Discarded Symbols): Likewise, and document
+ the meaning of "user-defined".
+ * tests/actions.at (Default %printer and %destructor for user-declared
+ end token): Rename to...
+ (Default %printer and %destructor for user-defined end token): ...
+ this.
+
+ * src/symtab.c (symbol_destructor_get, symbol_printer_get): In the
+ computation of whether to apply the default, don't maintain a list of
+ every Bison-defined symbol. Instead, just check for a first character
+ of '$', which a user symbol cannot have, and check for the error token.
+
+2006-08-21 Joel E. Denny <jdenny@ces.clemson.edu>
+
+ Don't apply the default %destructor or %printer to the error token,
+ $undefined, or $accept. This change fits the general rule that the
+ default %destructor and %printer are only for user-declared symbols,
+ and it solves several difficulties that are described in the new test
+ cases listed below.
+ * src/symtab.c (symbol_destructor_get, symbol_printer_get): Implement.
+ * tests/actions.at (Default %printer and %destructor are not for error
+ or $undefined, Default %printer and %destructor are not for $accept):
+ New test cases.
+
+2006-08-19 Joel E. Denny <jdenny@ces.clemson.edu>
+
+ Allow %start after the first rule.
+ * src/reader.c (grammar_current_rule_begin): Don't set the start symbol
+ when parsing the first rule.
+ (check_and_convert_grammar): Search for it here after all grammar
+ declarations have been parsed. Skip midrules, which have dummy LHS
+ nonterminals.
+ * src/symtab.c (symbol_is_dummy): New function.
+ * src/symtab.h (symbol_is_dummy): Declare it.
+ * tests/input.at (%start after first rule): New test.
+
+2006-08-18 Joel E. Denny <jdenny@ces.clemson.edu>
+
+ Redo some of the previous commit: add back the ability to use
+ non-aliased/undeclared string literals since it might be useful to
+ those declaring %token-table.
+ * src/reader.c (check_and_convert_grammar): Undo changes in previous
+ commit: don't worry about complaints from symbols_pack.
+ * src/symtab.c (symbol_new, symbol_class_set,
+ symbol_check_alias_consistency): Undo changes in previous commit: count
+ each string literal as a new symbol and token, assign it a symbol
+ number, and don't complain about non-aliased string literals.
+ (symbols_pack): Since symbol_make_alias still does not decrement symbol
+ and token counts but does still set aliased tokens to the same number,
+ symbol_pack_processor now leaves empty slots in the symbols array.
+ Remove those slots.
+ * tests/regression.at (Undeclared string literal): Remove test case
+ added in previous commit since non-aliased string literals are allowed
+ again.
+ (Characters Escapes, Web2c Actions): Undo changes in previous commit:
+ remove unnecessary string literal declarations.
+ * tests/sets.at (Firsts): Likewise.
+
+2006-08-18 Joel E. Denny <jdenny@ces.clemson.edu>
+
+ Don't allow an undeclared string literal, but allow a string literal to
+ be used before its declaration.
+ * src/reader.c (check_and_convert_grammar): Don't invoke packgram if
+ symbols_pack complained.
+ * src/symtab.c (symbol_new): Don't count a string literal as a new
+ symbol.
+ (symbol_class_set): Don't count a string literal as a new token, and
+ don't assign it a symbol number since symbol_make_alias does that.
+ (symbol_make_alias): It's not necessary to decrement the symbol and
+ token counts anymore. Don't assume that an alias declaration occurs
+ before any uses of the identifier or string, and thus don't assert that
+ one of them has the highest symbol number so far.
+ (symbol_check_alias_consistency): Complain if there's a string literal
+ that wasn't declared as an alias.
+ (symbols_pack): Bail if symbol_check_alias_consistency failed since
+ symbol_pack asserts that every token has been assigned a symbol number
+ although undeclared string literals have not.
+ * tests/regression.at (String alias declared after use, Undeclared
+ string literal): New test cases.
+ (Characters Escapes, Web2c Actions): Declare string literals as
+ aliases.
+ * tests/sets.at (Firsts): Likewise.
+
2006-08-14 Joel E. Denny <jdenny@ces.clemson.edu>
In the grammar scanner, STRING_FINISH unclosed constructs and return