%{ /* $NetBSD: cgram.y,v 1.516 2024/12/01 18:37:54 rillig Exp $ */ /* * Copyright (c) 1996 Christopher G. Demetriou. All Rights Reserved. * Copyright (c) 1994, 1995 Jochen Pohl * All Rights Reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Jochen Pohl for * The NetBSD Project. * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include #if defined(__RCSID) __RCSID("$NetBSD: cgram.y,v 1.516 2024/12/01 18:37:54 rillig Exp $"); #endif #include #include #include #include "lint1.h" extern char *yytext; /* * Contains the level of current declaration, used for symbol table entries. * 0 is the top-level, > 0 is inside a function body. */ int block_level; /* * level for memory allocation. Normally the same as block_level. * An exception is the declaration of parameters in prototypes. Memory * for these can't be freed after the declaration, but symbols must * be removed from the symbol table after the declaration. */ size_t mem_block_level; /* * Save the no-warns state and restore it to avoid the problem where * if (expr) { stmt } / * NOLINT * / stmt; */ #define LWARN_NOTHING_SAVED (-3) static int saved_lwarn = LWARN_NOTHING_SAVED; static void cgram_declare(sym_t *, bool, sbuf_t *); static void read_until_rparen(void); static balanced_token_sequence read_balanced_token_sequence(void); static sym_t *symbolrename(sym_t *, sbuf_t *); /* ARGSUSED */ static void clear_warning_flags_loc(const char *file, size_t line) { debug_step("%s:%zu: clearing flags", file, line); reset_suppressions(); saved_lwarn = LWARN_NOTHING_SAVED; } /* ARGSUSED */ static void save_warning_flags_loc(const char *file, size_t line) { debug_step("%s:%zu: saving flags %d", file, line, lwarn); saved_lwarn = lwarn; } /* ARGSUSED */ static void restore_warning_flags_loc(const char *file, size_t line) { if (saved_lwarn != LWARN_NOTHING_SAVED) { lwarn = saved_lwarn; debug_step("%s:%zu: restoring flags %d", file, line, lwarn); } else clear_warning_flags_loc(file, line); } #define clear_warning_flags() clear_warning_flags_loc(__FILE__, __LINE__) #define save_warning_flags() save_warning_flags_loc(__FILE__, __LINE__) #define restore_warning_flags() restore_warning_flags_loc(__FILE__, __LINE__) static bool is_either(const char *s, const char *a, const char *b) { return strcmp(s, a) == 0 || strcmp(s, b) == 0; } static void attribute_list_add(attribute_list *list, attribute attr) { if (list->len >= list->cap) { attribute *old_attrs = list->attrs; list->cap = 16 + 2 * list->cap; list->attrs = block_zero_alloc( list->cap * sizeof(*list->attrs), "attribute[]"); if (list->len > 0) memcpy(list->attrs, old_attrs, list->len * sizeof(*list->attrs)); } list->attrs[list->len++] = attr; } static void attribute_list_add_all(attribute_list *dst, attribute_list src) { for (size_t i = 0, n = src.len; i < n; i++) attribute_list_add(dst, src.attrs[i]); } static attribute new_attribute(const sbuf_t *prefix, const sbuf_t *name, const balanced_token_sequence *arg) { attribute attr = { .name = xstrdup(name->sb_name) }; if (prefix != NULL) attr.prefix = xstrdup(prefix->sb_name); if (arg != NULL) { attr.arg = block_zero_alloc(sizeof(*attr.arg), "balanced_token_sequence"); *attr.arg = *arg; } return attr; } #if YYDEBUG && YYBYACC #define YYSTYPE_TOSTRING cgram_to_string #endif %} %expect 110 %union { val_t *y_val; sbuf_t *y_name; sym_t *y_sym; bool y_inc; op_t y_op; scl_t y_scl; tspec_t y_tspec; type_qualifiers y_type_qualifiers; type_attributes y_type_attributes; function_specifier y_function_specifier; parameter_list y_parameter_list; function_call *y_arguments; type_t *y_type; tnode_t *y_tnode; range_t y_range; buffer *y_string; qual_ptr *y_qual_ptr; bool y_seen_statement; struct generic_association *y_generic; array_size y_array_size; bool y_in_system_header; designation y_designation; named_constant y_named_constant; attribute y_attribute; attribute_list y_attribute_list; balanced_token_sequence y_tokens; }; /* for Bison: %printer { if (is_integer($$->v_tspec)) fprintf(yyo, "%lld", (long long)$$->u.integer); else fprintf(yyo, "%Lg", $$->u.floating); } %printer { fprintf(yyo, "'%s'", $$ != NULL ? $$->sb_name : ""); } %printer { bool indented = debug_push_indented(true); debug_sym("", $$, ""); debug_pop_indented(indented); } %printer { fprintf(yyo, "%s", $$ ? "++" : "--"); } %printer { fprintf(yyo, "%s", op_name($$)); } %printer { fprintf(yyo, "%s", scl_name($$)); } %printer { fprintf(yyo, "%s", tspec_name($$)); } %printer { fprintf(yyo, "%s", type_qualifiers_string($$)); } %printer { fprintf(yyo, "%s", type_attributes_string($$)); } %printer { fprintf(yyo, "%s", function_specifier_name($$)); } %printer { size_t n = 0; for (const sym_t *p = $$.first; p != NULL; p = p->s_next) n++; fprintf(yyo, "%zu parameter%s", n, n != 1 ? "s" : ""); } %printer { fprintf(yyo, "%s", type_name($$)); } %printer { if ($$ == NULL) fprintf(yyo, ""); else fprintf(yyo, "%s '%s'", op_name($$->tn_op), type_name($$->tn_type)); } %printer { fprintf(yyo, "%zu to %zu", $$.lo, $$.hi); } %printer { fprintf(yyo, "length %zu", $$->len); } %printer { fprintf(yyo, "%s *", type_qualifiers_string($$->qualifiers)); } %printer { fprintf(yyo, "%s", $$ ? "yes" : "no"); } %printer { fprintf(yyo, "%s", type_name($$->ga_arg)); } %printer { fprintf(yyo, "%d", $$.dim); } %printer { fprintf(yyo, "%s", $$ ? "yes" : "no"); } %printer { if ($$.dn_len == 0) fprintf(yyo, "(empty)"); for (size_t i = 0; i < $$.dn_len; i++) { const designator *dr = $$.dn_items + i; if (dr->dr_kind == DK_MEMBER) fprintf(yyo, ".%s", dr->dr_member->s_name); else if (dr->dr_kind == DK_SUBSCRIPT) fprintf(yyo, "[%zu]", dr->dr_subscript); else fprintf(yyo, ""); } } %printer { fprintf(yyo, "%s", named_constant_name($$)); } */ %token T_LBRACE T_RBRACE T_LBRACK T_RBRACK T_LPAREN T_RPAREN %token T_POINT T_ARROW %token T_COMPLEMENT T_LOGNOT %token T_INCDEC %token T_SIZEOF %token T_BUILTIN_OFFSETOF %token T_TYPEOF %token T_EXTENSION %token T_ALIGNAS %token T_ALIGNOF %token T_ASTERISK %token T_MULTIPLICATIVE %token T_ADDITIVE %token T_SHIFT %token T_RELATIONAL %token T_EQUALITY %token T_AMPER %token T_BITXOR %token T_BITOR %token T_LOGAND %token T_LOGOR %token T_QUEST %token T_COLON %token T_ASSIGN %token T_OPASSIGN %token T_COMMA %token T_SEMI %token T_ELLIPSIS %token T_DCOLON %token T_REAL %token T_IMAG %token T_GENERIC /* storage classes (extern, static, auto, register and typedef) */ %token T_SCLASS %token T_FUNCTION_SPECIFIER /* * predefined type keywords (char, int, short, long, unsigned, signed, * float, double, void); see T_TYPENAME for types from typedef */ %token T_TYPE %token T_QUAL %token T_ATOMIC /* struct or union */ %token T_STRUCT_OR_UNION /* remaining keywords */ %token T_ASM %token T_BREAK %token T_CASE %token T_CONTINUE %token T_DEFAULT %token T_DO %token T_ELSE %token T_ENUM %token T_FOR %token T_GOTO %token T_IF %token T_PACKED %token T_RETURN %token T_SWITCH %token T_SYMBOLRENAME %token T_WHILE %token T_STATIC_ASSERT %token T_ATTRIBUTE %left T_THEN %left T_ELSE %right T_QUEST T_COLON %left T_LOGOR %left T_LOGAND %left T_BITOR %left T_BITXOR %left T_AMPER %left T_EQUALITY %left T_RELATIONAL %left T_SHIFT %left T_ADDITIVE %left T_ASTERISK T_MULTIPLICATIVE %token T_NAME %token T_TYPENAME %token T_CON %token T_NAMED_CONSTANT %token T_STRING /* No type for program. */ %type identifier_sym %type identifier %type string %type primary_expression %type member_designator %type generic_selection %type generic_assoc_list %type generic_association %type postfix_expression %type gcc_statement_expr_list %type gcc_statement_expr_item %type point_or_arrow %type argument_expression_list %type storage_class_specifiers %type unary_expression %type cast_expression %type expression_opt %type conditional_expression %type assignment_expression %type expression %type constant_expression /* No type for declaration_or_error. */ /* No type for declaration. */ /* No type for begin_type_declaration_specifiers. */ /* No type for begin_type_declmods. */ /* No type for begin_type_specifier_qualifier_list. */ /* No type for begin_type_specifier_qualifier_list_postfix. */ %type begin_type_typespec /* No type for begin_type_qualifier_list. */ /* No type for declmod. */ %type type_attribute_list_opt %type type_attribute_list %type type_attribute_opt %type type_attribute /* No type for begin_type. */ /* No type for end_type. */ /* No type for notype_init_declarator_list. */ /* No type for type_init_declarator_list. */ /* No type for notype_init_declarator. */ /* No type for type_init_declarator. */ %type storage_class_specifier %type type_type_specifier %type notype_type_specifier %type struct_or_union_specifier %type struct_or_union %type braced_member_declaration_list %type member_declaration_list_with_rbrace %type member_declaration_list %type member_declaration %type notype_member_declarator_list %type type_member_declarator_list %type notype_member_declarator %type type_member_declarator %type enum_specifier /* No type for enum. */ %type enum_declaration %type enums_with_opt_comma %type enumerator_list %type enumerator %type atomic_type_specifier /* No type for atomic. */ %type type_qualifier %type notype_declarator %type type_declarator %type notype_direct_declarator %type type_direct_declarator %type pointer %type type_qualifier_list_opt %type type_qualifier_list %type parameter_declaration %type type_param_declarator %type notype_param_declarator %type direct_param_declarator %type direct_notype_param_declarator %type param_list %type array_size_opt %type identifier_list %type type_name %type abstract_declaration %type abstract_decl_param_list /* No type for abstract_decl_lparen. */ %type vararg_parameter_type_list %type parameter_type_list %type abstract_declarator %type direct_abstract_declarator /* No type for braced_initializer. */ /* No type for initializer. */ /* No type for initializer_list. */ /* No type for designation. */ /* No type for designator_list. */ /* No type for designator. */ /* No type for static_assert_declaration. */ %type range /* No type for init_lbrace. */ /* No type for init_rbrace. */ %type attribute_specifier_sequence %type attribute_specifier %type attribute_list %type attribute %type attribute_argument_clause %type asm_or_symbolrename_opt /* No type for statement. */ /* No type for no_attr_statement. */ /* No type for non_expr_statement. */ /* No type for no_attr_non_expr_statement. */ /* No type for label. */ /* No type for labeled_statement. */ /* No type for compound_statement. */ /* No type for compound_statement_lbrace. */ /* No type for compound_statement_rbrace. */ %type block_item_list %type block_item /* No type for expression_statement. */ /* No type for selection_statement. */ /* No type for if_without_else. */ /* No type for if_expr. */ /* No type for switch_expr. */ /* No type for iteration_statement. */ /* No type for while_expr. */ /* No type for do_statement. */ /* No type for do. */ /* No type for for_start. */ /* No type for for_exprs. */ /* No type for jump_statement. */ /* No type for goto. */ /* No type for asm_statement. */ /* No type for read_until_rparen. */ /* No type for translation_unit. */ /* No type for external_declaration. */ /* No type for top_level_declaration. */ /* No type for function_definition. */ %type func_declarator /* No type for arg_declaration_list_opt. */ /* No type for arg_declaration_list. */ /* No type for arg_declaration. */ %type gcc_attribute_specifier_list_opt %type gcc_attribute_specifier_list %type gcc_attribute_specifier %type gcc_attribute_list %type gcc_attribute %type sys %% program: /* empty */ { /* TODO: Make this an error in C99 mode as well. */ if (!allow_trad && !allow_c99) /* empty translation unit */ error(272); else if (allow_c90) /* empty translation unit */ warning(272); } | translation_unit ; identifier_sym: /* helper for struct/union/enum */ identifier { $$ = getsym($1); } ; /* K&R ???, C90 ???, C99 6.4.2.1, C11 ??? */ identifier: T_NAME { debug_step("cgram: name '%s'", $1->sb_name); $$ = $1; } | T_TYPENAME { debug_step("cgram: typename '%s'", $1->sb_name); $$ = $1; } ; /* see C99 6.4.5, string literals are joined by 5.1.1.2 */ string: T_STRING | string T_STRING { if (!allow_c90) /* concatenated strings are illegal in traditional C */ warning(219); $$ = cat_strings($1, $2); } ; /* K&R 7.1, C90 ???, C99 6.5.1, C11 6.5.1, C23 6.5.2 */ primary_expression: T_NAME { bool sys_name, sys_next; sys_name = in_system_header; if (yychar < 0) yychar = yylex(); sys_next = in_system_header; in_system_header = sys_name; $$ = build_name(getsym($1), yychar == T_LPAREN); in_system_header = sys_next; } | T_CON { $$ = build_constant(gettyp($1->v_tspec), $1); } | T_NAMED_CONSTANT { if ($1 == NC_NULLPTR) { tnode_t *zero = expr_alloc_tnode(); zero->tn_op = CON; zero->tn_type = gettyp(INT); zero->u.value.v_tspec = INT; type_t *void_ptr = block_derive_type(gettyp(VOID), PTR); $$ = convert(CVT, 0, void_ptr, zero); $$->tn_sys = zero->tn_sys; } else { tnode_t *nc = expr_alloc_tnode(); nc->tn_op = CON; nc->tn_type = gettyp(BOOL); nc->u.value.v_tspec = BOOL; nc->u.value.u.integer = $1 == NC_TRUE ? 1 : 0; $$ = nc; } } | string { $$ = build_string($1); } | T_LPAREN expression T_RPAREN { if ($2 != NULL) $2->tn_parenthesized = true; $$ = $2; } | generic_selection /* GCC primary-expression, see c_parser_postfix_expression */ | T_BUILTIN_OFFSETOF T_LPAREN type_name T_COMMA { set_sym_kind(SK_MEMBER); } member_designator T_RPAREN { $$ = build_offsetof($3, $6); } ; /* K&R ---, C90 ---, C99 7.17p3, C11 7.19p3, C23 7.21p4 */ member_designator: identifier { $$ = (designation) { .dn_len = 0 }; designation_push(&$$, DK_MEMBER, getsym($1), 0); } | member_designator T_LBRACK range T_RBRACK { $$ = $1; designation_push(&$$, DK_SUBSCRIPT, NULL, $3.lo); } | member_designator T_POINT { set_sym_kind(SK_MEMBER); } identifier { $$ = $1; designation_push(&$$, DK_MEMBER, getsym($4), 0); } ; /* K&R ---, C90 ---, C99 ---, C11 6.5.1.1, C23 6.5.2.1 */ generic_selection: T_GENERIC T_LPAREN assignment_expression T_COMMA generic_assoc_list T_RPAREN { /* generic selection requires C11 or later */ c11ism(345); $$ = build_generic_selection($3, $5); } ; /* K&R ---, C90 ---, C99 ---, C11 6.5.1.1, C23 6.5.2.1 */ generic_assoc_list: generic_association | generic_assoc_list T_COMMA generic_association { $3->ga_prev = $1; $$ = $3; } ; /* K&R ---, C90 ---, C99 ---, C11 6.5.1.1, C23 6.5.2.1 */ generic_association: type_name T_COLON assignment_expression { $$ = block_zero_alloc(sizeof(*$$), "generic"); $$->ga_arg = $1; $$->ga_result = $3; } | T_DEFAULT T_COLON assignment_expression { $$ = block_zero_alloc(sizeof(*$$), "generic"); $$->ga_arg = NULL; $$->ga_result = $3; } ; /* K&R 7.1, C90 ???, C99 6.5.2, C11 6.5.2, C23 6.5.3.1 */ postfix_expression: primary_expression | postfix_expression T_LBRACK sys expression T_RBRACK { $$ = build_unary(INDIR, $3, build_binary($1, PLUS, $3, $4)); } | postfix_expression T_LPAREN sys T_RPAREN { function_call *call = expr_zero_alloc(sizeof(*call), "function_call"); $$ = build_function_call($1, $3, call); } | postfix_expression T_LPAREN sys argument_expression_list T_RPAREN { $$ = build_function_call($1, $3, $4); } | postfix_expression point_or_arrow sys T_NAME { $$ = build_member_access($1, $2, $3, $4); } | postfix_expression T_INCDEC sys { $$ = build_unary($2 ? INCAFT : DECAFT, $3, $1); } /* Rule 'compound_literal' from C99 6.5.2.5. */ | T_LPAREN type_name T_RPAREN { sym_t *tmp = mktempsym($2); begin_initialization(tmp); cgram_declare(tmp, true, NULL); } braced_initializer { if (!allow_c99) /* compound literals are a C99/GCC extension */ gnuism(319); $$ = build_name(current_initsym(), false); end_initialization(); } /* Rule 'compound_literal' with storage classes from C23 6.5.3.6. */ | T_LPAREN storage_class_specifiers type_name T_RPAREN { sym_t *tmp = mktempsym($3); tmp->s_scl = $2; begin_initialization(tmp); cgram_declare(tmp, true, NULL); } braced_initializer { if (!allow_c99) /* compound literals are a C99/GCC extension */ gnuism(319); $$ = build_name(current_initsym(), false); end_initialization(); } | T_LPAREN compound_statement_lbrace { begin_statement_expr(); } gcc_statement_expr_list { do_statement_expr($4); } compound_statement_rbrace T_RPAREN { $$ = end_statement_expr(); } ; /* * The inner part of a GCC statement-expression of the form ({ ... }). * * https://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html */ gcc_statement_expr_list: gcc_statement_expr_item | gcc_statement_expr_list gcc_statement_expr_item { $$ = $2; } ; gcc_statement_expr_item: declaration_or_error { clear_warning_flags(); $$ = NULL; } | non_expr_statement { $$ = expr_alloc_tnode(); $$->tn_type = gettyp(VOID); } | T_SEMI { $$ = expr_alloc_tnode(); $$->tn_type = gettyp(VOID); } | expression T_SEMI { if ($1 == NULL) { /* in case of syntax errors */ $$ = expr_alloc_tnode(); $$->tn_type = gettyp(VOID); } else { /* XXX: do that only on the last name */ if ($1->tn_op == NAME) $1->u.sym->s_used = true; expr($1, true, false, false, false, "statement expression"); suppress_fallthrough = false; $$ = $1; } } ; point_or_arrow: /* helper for 'postfix_expression' */ T_POINT { set_sym_kind(SK_MEMBER); $$ = POINT; } | T_ARROW { set_sym_kind(SK_MEMBER); $$ = ARROW; } ; /* K&R 7.1, C90 ???, C99 6.5.2, C11 6.5.2, C23 6.5.3.1 */ argument_expression_list: assignment_expression { $$ = expr_zero_alloc(sizeof(*$$), "function_call"); add_function_argument($$, $1); } | argument_expression_list T_COMMA assignment_expression { $$ = $1; add_function_argument($1, $3); } ; /* C23 6.5.3.6 */ /* The rule 'compound_literal' is inlined into 'postfix_expression'. */ /* C23 6.5.3.6 */ storage_class_specifiers: storage_class_specifier | storage_class_specifiers storage_class_specifier { // TODO C23: maybe merge multiple storage class specifiers $$ = $1; } ; /* K&R 7.2, C90 ???, C99 6.5.3, C11 6.5.3, C23 6.5.4 */ unary_expression: postfix_expression | T_INCDEC sys unary_expression { $$ = build_unary($1 ? INCBEF : DECBEF, $2, $3); } | T_AMPER sys cast_expression { $$ = build_unary(ADDR, $2, $3); } | T_ASTERISK sys cast_expression { $$ = build_unary(INDIR, $2, $3); } | T_ADDITIVE sys cast_expression { if (!allow_c90 && $1 == PLUS) /* unary '+' is illegal in traditional C */ warning(100); $$ = build_unary($1 == PLUS ? UPLUS : UMINUS, $2, $3); } | T_COMPLEMENT sys cast_expression { $$ = build_unary(COMPL, $2, $3); } | T_LOGNOT sys cast_expression { $$ = build_unary(NOT, $2, $3); } | T_REAL sys cast_expression { /* GCC c_parser_unary_expression */ $$ = build_unary(REAL, $2, $3); } | T_IMAG sys cast_expression { /* GCC c_parser_unary_expression */ $$ = build_unary(IMAG, $2, $3); } | T_EXTENSION cast_expression { /* GCC c_parser_unary_expression */ $$ = $2; } | T_SIZEOF unary_expression { $$ = $2 == NULL ? NULL : build_sizeof($2->tn_type); if ($$ != NULL) check_expr_misc($2, false, false, false, false, false, true); } | T_SIZEOF T_LPAREN type_name T_RPAREN { $$ = build_sizeof($3); } | T_ALIGNOF unary_expression { /* non type argument to alignof is a GCC extension */ gnuism(349); lint_assert($2 != NULL); $$ = build_alignof($2->tn_type); } /* K&R ---, C90 ---, C99 ---, C11 6.5.3, C23 6.5.4.4 */ | T_ALIGNOF T_LPAREN type_name T_RPAREN { /* TODO: c11ism */ $$ = build_alignof($3); } ; /* C23 6.5.4 */ /* The rule 'unary_operator' is inlined into unary_expression. */ /* K&R 7.2, C90 ???, C99 6.5.4, C11 6.5.4, C23 6.5.5 */ cast_expression: unary_expression | T_LPAREN type_name T_RPAREN sys cast_expression { $$ = cast($5, $4, $2); } ; expression_opt: /* empty */ { $$ = NULL; } | expression ; /* 'conditional_expression' also implements 'multiplicative_expression'. */ /* 'conditional_expression' also implements 'additive_expression'. */ /* 'conditional_expression' also implements 'shift_expression'. */ /* 'conditional_expression' also implements 'relational_expression'. */ /* 'conditional_expression' also implements 'equality_expression'. */ /* 'conditional_expression' also implements 'AND_expression'. */ /* 'conditional_expression' also implements 'exclusive_OR_expression'. */ /* 'conditional_expression' also implements 'inclusive_OR_expression'. */ /* 'conditional_expression' also implements 'logical_AND_expression'. */ /* 'conditional_expression' also implements 'logical_OR_expression'. */ /* K&R ???, C90 ???, C99 6.5.5 to 6.5.15, C11 6.5.5 to 6.5.15, C23 6.5.6 to 6.5.16 */ conditional_expression: cast_expression | conditional_expression T_ASTERISK sys conditional_expression { $$ = build_binary($1, MULT, $3, $4); } | conditional_expression T_MULTIPLICATIVE sys conditional_expression { $$ = build_binary($1, $2, $3, $4); } | conditional_expression T_ADDITIVE sys conditional_expression { $$ = build_binary($1, $2, $3, $4); } | conditional_expression T_SHIFT sys conditional_expression { $$ = build_binary($1, $2, $3, $4); } | conditional_expression T_RELATIONAL sys conditional_expression { $$ = build_binary($1, $2, $3, $4); } | conditional_expression T_EQUALITY sys conditional_expression { $$ = build_binary($1, $2, $3, $4); } | conditional_expression T_AMPER sys conditional_expression { $$ = build_binary($1, BITAND, $3, $4); } | conditional_expression T_BITXOR sys conditional_expression { $$ = build_binary($1, BITXOR, $3, $4); } | conditional_expression T_BITOR sys conditional_expression { $$ = build_binary($1, BITOR, $3, $4); } | conditional_expression T_LOGAND sys conditional_expression { $$ = build_binary($1, LOGAND, $3, $4); } | conditional_expression T_LOGOR sys conditional_expression { $$ = build_binary($1, LOGOR, $3, $4); } | conditional_expression T_QUEST sys expression T_COLON sys conditional_expression { $$ = build_binary($1, QUEST, $3, build_binary($4, COLON, $6, $7)); } ; /* K&R ???, C90 ???, C99 6.5.16, C11 6.5.16, C23 6.5.17.1 */ assignment_expression: conditional_expression | unary_expression T_ASSIGN sys assignment_expression { $$ = build_binary($1, ASSIGN, $3, $4); } | unary_expression T_OPASSIGN sys assignment_expression { $$ = build_binary($1, $2, $3, $4); } ; /* C23 6.5.17.1 */ /* The rule 'assignment_operator' is inlined into 'assignment_expression'. */ /* K&R ???, C90 ???, C99 6.5.17, C11 6.5.17, C23 6.5.18 */ expression: assignment_expression | expression T_COMMA sys assignment_expression { $$ = build_binary($1, COMMA, $3, $4); } ; /* K&R ???, C90 ???, C99 6.6, C11 ???, C23 6.6 */ constant_expression: conditional_expression ; declaration_or_error: declaration | error T_SEMI ; /* K&R ???, C90 ???, C99 6.7, C11 ???, C23 6.7.1 */ declaration: begin_type_declmods end_type T_SEMI { if (dcs->d_scl == TYPEDEF) /* typedef declares no type name */ warning(72); else /* empty declaration */ warning(2); } | begin_type_declmods end_type notype_init_declarator_list T_SEMI { if (dcs->d_scl == TYPEDEF) /* syntax error '%s' */ error(249, "missing base type for typedef"); else /* old-style declaration; add 'int' */ error(1); } | begin_type_declaration_specifiers end_type T_SEMI { if (dcs->d_scl == TYPEDEF) /* typedef declares no type name */ warning(72); else if (!dcs->d_nonempty_decl) /* empty declaration */ warning(2); } | begin_type_declaration_specifiers end_type type_init_declarator_list T_SEMI | static_assert_declaration ; /* TODO: Implement 'declaration_specifiers' from C23 6.7.1. */ begin_type_declaration_specifiers: /* see C99 6.7, C23 6.7.1 */ begin_type_typespec { dcs_add_type($1); } | begin_type_declmods type_type_specifier { dcs_add_type($2); } | type_attribute begin_type_declaration_specifiers { if ($1.used) dcs_set_used(); if ($1.noreturn) dcs->d_noreturn = true; } | begin_type_declaration_specifiers declmod | begin_type_declaration_specifiers notype_type_specifier { dcs_add_type($2); } ; begin_type_declmods: /* see C99 6.7 */ begin_type type_qualifier { dcs_add_qualifiers($2); } | begin_type T_SCLASS { dcs_add_storage_class($2); } | begin_type T_FUNCTION_SPECIFIER { dcs_add_function_specifier($2); } | begin_type_declmods declmod ; begin_type_specifier_qualifier_list: /* see C11 6.7.2.1 */ begin_type_specifier_qualifier_list_postfix | type_attribute_list begin_type_specifier_qualifier_list_postfix ; begin_type_specifier_qualifier_list_postfix: begin_type_typespec { dcs_add_type($1); } | begin_type_qualifier_list type_type_specifier { dcs_add_type($2); } | begin_type_specifier_qualifier_list_postfix type_qualifier { dcs_add_qualifiers($2); } | begin_type_specifier_qualifier_list_postfix notype_type_specifier { dcs_add_type($2); } | begin_type_specifier_qualifier_list_postfix type_attribute ; begin_type_typespec: begin_type notype_type_specifier { $$ = $2; } | begin_type T_TYPENAME { $$ = getsym($2)->s_type; } ; begin_type_qualifier_list: begin_type type_qualifier { dcs_add_qualifiers($2); } | begin_type_qualifier_list type_qualifier { dcs_add_qualifiers($2); } ; declmod: type_qualifier { dcs_add_qualifiers($1); } | T_SCLASS { dcs_add_storage_class($1); } | T_FUNCTION_SPECIFIER { dcs_add_function_specifier($1); } | type_attribute_list { if ($1.used) dcs_set_used(); if ($1.noreturn) dcs->d_noreturn = true; } ; type_attribute_list_opt: /* empty */ { $$ = (type_attributes){ .used = false }; } | type_attribute_list ; type_attribute_list: type_attribute | type_attribute_list type_attribute { $$ = (type_attributes){ .used = $1.used || $2.used }; } ; type_attribute_opt: /* empty */ { $$ = (type_attributes){ .used = false }; } | type_attribute ; type_attribute: /* See C11 6.7 declaration-specifiers */ gcc_attribute_specifier | T_ALIGNAS T_LPAREN type_type_specifier T_RPAREN { /* C11 6.7.5 */ dcs_add_alignas(build_sizeof($3)); $$ = (type_attributes){ .used = false }; } | T_ALIGNAS T_LPAREN constant_expression T_RPAREN { /* C11 6.7.5 */ dcs_add_alignas($3); $$ = (type_attributes){ .used = false }; } | T_PACKED { dcs_add_packed(); $$ = (type_attributes){ .used = false }; } ; begin_type: /* empty */ { dcs_begin_type(); } | attribute_specifier_sequence { dcs_begin_type(); dcs->d_used = attributes_contain(&$1, "maybe_unused"); dcs->d_noreturn = attributes_contain(&$1, "noreturn"); } ; end_type: /* empty */ { dcs_end_type(); } ; /* TODO: Implement 'declaration_specifier' from C23 6.7.1. */ /* * For an explanation of 'type' and 'notype' prefixes in the following rules, * see https://www.gnu.org/software/bison/manual/bison.html#Semantic-Tokens. */ /* C23 6.7.1 */ /* The rule 'init_declarator_list' is split into the 'notype' and 'type' variants. */ notype_init_declarator_list: notype_init_declarator | notype_init_declarator_list T_COMMA type_init_declarator ; type_init_declarator_list: type_init_declarator | type_init_declarator_list T_COMMA type_init_declarator ; /* C23 6.7.1 */ /* The rule 'init_declarator' is split into the 'notype' and 'type' variants. */ notype_init_declarator: notype_declarator asm_or_symbolrename_opt { cgram_declare($1, false, $2); check_size($1); } | notype_declarator asm_or_symbolrename_opt { begin_initialization($1); cgram_declare($1, true, $2); } T_ASSIGN initializer { check_size($1); end_initialization(); } ; type_init_declarator: type_declarator asm_or_symbolrename_opt { cgram_declare($1, false, $2); check_size($1); } | type_declarator asm_or_symbolrename_opt { begin_initialization($1); cgram_declare($1, true, $2); } T_ASSIGN initializer { if ($1->s_type->t_tspec != AUTO_TYPE) check_size($1); end_initialization(); } ; /* TODO: Implement 'attribute_declaration' from C23 6.7.1. */ /* K&R ???, C90 ???, C99 ???, C11 ???, C23 6.7.2 */ storage_class_specifier: T_SCLASS ; /* C99 6.7.2, C23 6.7.3.1 */ /* The rule 'type_specifier' is split into the 'notype' and 'type' variants. */ type_type_specifier: notype_type_specifier | T_TYPENAME { $$ = getsym($1)->s_type; } ; notype_type_specifier: /* see C99 6.7.2 */ T_TYPE { $$ = gettyp($1); } | T_TYPEOF T_LPAREN expression T_RPAREN { /* GCC extension */ $$ = $3 != NULL ? block_dup_type($3->tn_type) : gettyp(INT); $$->t_typeof = true; } | atomic_type_specifier | struct_or_union_specifier { end_declaration_level(); $$ = $1; } | enum_specifier { end_declaration_level(); $$ = $1; } ; /* K&R ---, C90 ---, C99 6.7.2.1, C11 ???, C23 6.7.3.2 */ struct_or_union_specifier: struct_or_union identifier_sym { /* * STDC requires that "struct a;" always introduces * a new tag if "a" is not declared at current level * * yychar is valid because otherwise the parser would not * have been able to decide if it must shift or reduce */ $$ = make_tag_type($2, $1, false, yychar == T_SEMI); } | struct_or_union identifier_sym { dcs->d_tag_type = make_tag_type($2, $1, true, false); } braced_member_declaration_list { $$ = complete_struct_or_union($4); } | struct_or_union { dcs->d_tag_type = make_tag_type(NULL, $1, true, false); } braced_member_declaration_list { $$ = complete_struct_or_union($3); } | struct_or_union error { set_sym_kind(SK_VCFT); $$ = gettyp(INT); } ; /* K&R ---, C90 ---, C99 6.7.2.1, C11 ???, C23 6.7.3.2 */ struct_or_union: T_STRUCT_OR_UNION { set_sym_kind(SK_TAG); begin_declaration_level($1 == STRUCT ? DLK_STRUCT : DLK_UNION); dcs->d_sou_size_in_bits = 0; dcs->d_sou_align = 1; $$ = $1; } | struct_or_union type_attribute ; braced_member_declaration_list: /* see C99 6.7.2.1 */ T_LBRACE { set_sym_kind(SK_VCFT); } member_declaration_list_with_rbrace { $$ = $3; } ; member_declaration_list_with_rbrace: /* see C99 6.7.2.1 */ member_declaration_list T_RBRACE | T_RBRACE { /* XXX: Allowed since C23. */ $$ = NULL; } ; /* K&R ???, C90 ???, C99 6.7.2.1, C11 6.7.2.1, C23 6.7.3.2 */ /* Was named struct_declaration_list until C11. */ member_declaration_list: member_declaration | member_declaration_list member_declaration { $$ = concat_symbols($1, $2); } ; /* K&R ???, C90 ???, C99 6.7.2.1, C11 6.7.2.1, C23 6.7.3.2 */ /* Was named struct_declaration until C11. */ member_declaration: begin_type_qualifier_list end_type { /* ^^ There is no check for the missing type-specifier. */ /* too late, i know, but getsym() compensates it */ set_sym_kind(SK_MEMBER); } notype_member_declarator_list T_SEMI { set_sym_kind(SK_VCFT); $$ = $4; } | begin_type_specifier_qualifier_list end_type { set_sym_kind(SK_MEMBER); } type_member_declarator_list T_SEMI { set_sym_kind(SK_VCFT); $$ = $4; } | begin_type_qualifier_list end_type type_attribute_opt T_SEMI { /* syntax error '%s' */ error(249, "member without type"); $$ = NULL; } | begin_type_specifier_qualifier_list end_type T_SEMI { set_sym_kind(SK_VCFT); if (!allow_c11 && !allow_gcc) /* anonymous struct/union members is a C11 feature */ warning(49); if (is_struct_or_union(dcs->d_type->t_tspec)) $$ = declare_unnamed_member(); else { /* syntax error '%s' */ error(249, "unnamed member"); $$ = NULL; } } | static_assert_declaration { $$ = NULL; } | error T_SEMI { set_sym_kind(SK_VCFT); $$ = NULL; } ; /* TODO: Implement 'specifier_qualifier_list' from C23 6.7.3.2. */ /* TODO: Implement 'type_specifier_qualifier' from C23 6.7.3.2. */ /* C23 6.7.3.2 */ /* The rule 'member_declarator_list' is split into the 'type' and 'notype' variants. */ /* Was named struct_declarator_list until C11. */ notype_member_declarator_list: notype_member_declarator { $$ = declare_member($1); } | notype_member_declarator_list { set_sym_kind(SK_MEMBER); } T_COMMA type_member_declarator { $$ = concat_symbols($1, declare_member($4)); } ; type_member_declarator_list: type_member_declarator { $$ = declare_member($1); } | type_member_declarator_list { set_sym_kind(SK_MEMBER); } T_COMMA type_member_declarator { $$ = concat_symbols($1, declare_member($4)); } ; /* C23 6.7.3.2 */ /* The rule 'member_declarator' is split into the 'type' and 'notype' variants. */ /* Was named struct_declarator until C11. */ notype_member_declarator: notype_declarator /* C99 6.7.2.1 */ | notype_declarator T_COLON constant_expression { $$ = set_bit_field_width($1, to_int_constant($3, true)); } /* C99 6.7.2.1 */ | { set_sym_kind(SK_VCFT); } T_COLON constant_expression { $$ = set_bit_field_width(NULL, to_int_constant($3, true)); } ; type_member_declarator: type_declarator | type_declarator T_COLON constant_expression type_attribute_list_opt { $$ = set_bit_field_width($1, to_int_constant($3, true)); } | { set_sym_kind(SK_VCFT); } T_COLON constant_expression type_attribute_list_opt { $$ = set_bit_field_width(NULL, to_int_constant($3, true)); } ; /* K&R ---, C90 6.5.2.2, C99 6.7.2.2, C11 6.7.2.2, C23 6.7.3.5 */ enum_specifier: enum gcc_attribute_specifier_list_opt identifier_sym { $$ = make_tag_type($3, ENUM, false, false); } | enum gcc_attribute_specifier_list_opt identifier_sym { dcs->d_tag_type = make_tag_type($3, ENUM, true, false); } enum_declaration /*gcc_attribute_specifier_list_opt*/ { $$ = complete_enum($5); } | enum gcc_attribute_specifier_list_opt { dcs->d_tag_type = make_tag_type(NULL, ENUM, true, false); } enum_declaration /*gcc_attribute_specifier_list_opt*/ { $$ = complete_enum($4); } | enum error { set_sym_kind(SK_VCFT); $$ = gettyp(INT); } ; enum: /* helper for C99 6.7.2.2 */ T_ENUM { set_sym_kind(SK_TAG); begin_declaration_level(DLK_ENUM); } ; enum_declaration: /* helper for C99 6.7.2.2 */ T_LBRACE { set_sym_kind(SK_VCFT); enumval = 0; } enums_with_opt_comma T_RBRACE { $$ = $3; } ; enums_with_opt_comma: /* helper for C99 6.7.2.2 */ enumerator_list | enumerator_list T_COMMA { if (!allow_c99 && !allow_trad) /* trailing ',' in enum declaration requires C99 ... */ error(54); else /* trailing ',' in enum declaration requires C99 ... */ c99ism(54); $$ = $1; } ; /* C99 6.7.2.2, C23 6.7.3.3 */ enumerator_list: enumerator | enumerator_list T_COMMA enumerator { $$ = concat_symbols($1, $3); } | error { $$ = NULL; } ; /* C99 6.7.2.2, C23 6.7.3.3 */ enumerator: identifier_sym gcc_attribute_specifier_list_opt { $$ = enumeration_constant($1, enumval, true); } | identifier_sym gcc_attribute_specifier_list_opt T_ASSIGN constant_expression { $$ = enumeration_constant($1, to_int_constant($4, true), false); } ; /* TODO: Implement 'enum_type_specifier' from C23 6.7.3.3. */ /* K&R ---, C90 ---, C99 ---, C11 6.7.2.4, C23 6.7.3.5 */ atomic_type_specifier: atomic T_LPAREN type_name T_RPAREN { $$ = $3; } ; atomic: /* helper */ T_ATOMIC { /* TODO: First fix c11ism, then use it here. */ if (!allow_c11) /* '_Atomic' requires C11 or later */ error(350); } ; /* TODO: Implement 'typeof_specifier' from C23 6.7.3.6. */ /* TODO: Implement 'typeof_specifier_argument' from C23 6.7.3.6. */ /* C99 6.7.3, C23 6.7.4.1 */ type_qualifier: T_QUAL | atomic { $$ = (type_qualifiers){ .tq_atomic = true }; } ; /* TODO: Implement 'function_specifier' from C23 6.7.5. */ /* TODO: Implement 'alignment_specifier' from C23 6.7.6. */ /* C23 6.7.7.1 */ /* The rule 'declarator' is split into the 'notype' and 'type' variants. */ notype_declarator: notype_direct_declarator | pointer notype_direct_declarator { $$ = add_pointer($2, $1); } ; type_declarator: type_direct_declarator | pointer type_direct_declarator { $$ = add_pointer($2, $1); } ; /* C23 6.7.7.1 */ /* The rule 'direct_declarator' is split into the 'notype' and 'type' variants. */ notype_direct_declarator: type_attribute_list_opt T_NAME { $$ = declarator_name(getsym($2)); } | type_attribute_list_opt T_LPAREN type_declarator T_RPAREN { $$ = $3; } | notype_direct_declarator T_LBRACK array_size_opt T_RBRACK { $$ = add_array($1, $3.has_dim, $3.dim); } | notype_direct_declarator param_list asm_or_symbolrename_opt { $$ = add_function(symbolrename($1, $3), $2); end_declaration_level(); block_level--; } | notype_direct_declarator type_attribute ; type_direct_declarator: type_attribute_list_opt identifier { $$ = declarator_name(getsym($2)); } | type_attribute_list_opt T_LPAREN type_declarator T_RPAREN { $$ = $3; } | type_direct_declarator T_LBRACK array_size_opt T_RBRACK { $$ = add_array($1, $3.has_dim, $3.dim); } | type_direct_declarator param_list asm_or_symbolrename_opt { $$ = add_function(symbolrename($1, $3), $2); end_declaration_level(); block_level--; if ($2.used) $$->s_used = true; } | type_direct_declarator type_attribute { $$ = $1; if ($2.used) $$->s_used = true; } ; /* TODO: Implement 'array_declarator' from C23 6.7.7.1. */ /* TODO: Implement 'function_declarator' from C23 6.7.7.1. */ /* C99 6.7.5, C23 6.7.7.1 */ pointer: T_ASTERISK type_qualifier_list_opt { $$ = xcalloc(1, sizeof(*$$)); add_type_qualifiers(&$$->qualifiers, $2); } | T_ASTERISK type_qualifier_list_opt pointer { $$ = xcalloc(1, sizeof(*$$)); add_type_qualifiers(&$$->qualifiers, $2); $$ = append_qualified_pointer($$, $3); } ; /* see C99 6.7.5, C23 6.7.7.1 */ type_qualifier_list_opt: /* empty */ { $$ = (type_qualifiers){ .tq_const = false }; } | type_qualifier_list ; /* C99 6.7.5 */ type_qualifier_list: type_qualifier | type_qualifier_list type_qualifier { $$ = $1; add_type_qualifiers(&$$, $2); } ; /* TODO: Implement 'parameter_type_list' from C23 6.7.7.1. */ /* TODO: Implement 'parameter_list' from C23 6.7.7.1. */ /* C23 6.7.7.1 */ /* XXX: C99 6.7.5 defines the same name, but it looks completely different. */ parameter_declaration: begin_type_declmods end_type { /* ^^ There is no check for the missing type-specifier. */ $$ = declare_parameter(abstract_name(), false); } | begin_type_declaration_specifiers end_type { $$ = declare_parameter(abstract_name(), false); } | begin_type_declmods end_type notype_param_declarator { /* ^^ There is no check for the missing type-specifier. */ $$ = declare_parameter($3, false); } /* * type_param_declarator is needed because of following conflict: * "typedef int a; f(int (a));" could be parsed as * "function with argument a of type int", or * "function with an unnamed (abstract) argument of type function". * This grammar realizes the second case. */ | begin_type_declaration_specifiers end_type type_param_declarator { $$ = declare_parameter($3, false); } | begin_type_declmods end_type abstract_declarator { /* ^^ There is no check for the missing type-specifier. */ $$ = declare_parameter($3, false); } | begin_type_declaration_specifiers end_type abstract_declarator { $$ = declare_parameter($3, false); } ; /* * The two distinct rules type_param_declarator and notype_param_declarator * avoid a conflict in parameter lists. A typename enclosed in parentheses is * always treated as a typename, not an argument name. For example, after * "typedef double a;", the declaration "f(int (a));" is interpreted as * "f(int (double));", not "f(int a);". */ type_param_declarator: direct_param_declarator | pointer direct_param_declarator { $$ = add_pointer($2, $1); } ; notype_param_declarator: direct_notype_param_declarator | pointer direct_notype_param_declarator { $$ = add_pointer($2, $1); } ; direct_param_declarator: identifier type_attribute_list { $$ = declarator_name(getsym($1)); if ($2.used) dcs_set_used(); } | identifier { $$ = declarator_name(getsym($1)); } | T_LPAREN notype_param_declarator T_RPAREN { $$ = $2; } | direct_param_declarator T_LBRACK array_size_opt T_RBRACK gcc_attribute_specifier_list_opt { $$ = add_array($1, $3.has_dim, $3.dim); if ($5.used) dcs_set_used(); } | direct_param_declarator param_list asm_or_symbolrename_opt { $$ = add_function(symbolrename($1, $3), $2); end_declaration_level(); block_level--; if ($2.used) dcs_set_used(); } ; direct_notype_param_declarator: identifier { $$ = declarator_name(getsym($1)); } | T_LPAREN notype_param_declarator T_RPAREN { $$ = $2; } | direct_notype_param_declarator T_LBRACK array_size_opt T_RBRACK { $$ = add_array($1, $3.has_dim, $3.dim); } | direct_notype_param_declarator param_list asm_or_symbolrename_opt { $$ = add_function(symbolrename($1, $3), $2); end_declaration_level(); block_level--; } ; param_list: T_LPAREN { block_level++; begin_declaration_level(DLK_PROTO_PARAMS); } identifier_list T_RPAREN { $$ = (parameter_list){ .first = $3 }; if (allow_c23) /* function definition with identifier list is ... */ error(384); else if (allow_c99) /* function definition with identifier list is ... */ warning(384); } | abstract_decl_param_list ; array_size_opt: /* empty */ { $$.has_dim = false; $$.dim = 0; } | T_ASTERISK { /* since C99; variable length array of unspecified size */ $$.has_dim = false; /* TODO: maybe change to true */ $$.dim = 0; /* just as a placeholder */ } | type_qualifier_list_opt T_SCLASS constant_expression { /* C11 6.7.6.3p7 */ if ($2 != STATIC) yyerror("Bad attribute"); /* static array size requires C11 or later */ c11ism(343); $$.has_dim = true; $$.dim = $3 == NULL ? 0 : to_int_constant($3, false); } | type_qualifier { /* C11 6.7.6.2 */ if (!$1.tq_restrict) yyerror("Bad attribute"); $$.has_dim = true; $$.dim = 0; } | constant_expression { $$.has_dim = true; $$.dim = $1 == NULL ? 0 : to_int_constant($1, false); } ; identifier_list: /* C99 6.7.5 */ T_NAME { $$ = old_style_function_parameter_name(getsym($1)); } | identifier_list T_COMMA T_NAME { $$ = concat_symbols($1, old_style_function_parameter_name(getsym($3))); } | identifier_list error ; /* C99 6.7.6, C23 6.7.8 */ /* XXX: C99 requires an additional specifier-qualifier-list. */ type_name: { begin_declaration_level(DLK_ABSTRACT); } abstract_declaration { end_declaration_level(); $$ = $2->s_type; } ; abstract_declaration: /* specific to lint */ begin_type_qualifier_list end_type { $$ = declare_abstract_type(abstract_name()); } | begin_type_specifier_qualifier_list end_type { $$ = declare_abstract_type(abstract_name()); } | begin_type_qualifier_list end_type abstract_declarator { $$ = declare_abstract_type($3); } | begin_type_specifier_qualifier_list end_type abstract_declarator { $$ = declare_abstract_type($3); } ; abstract_decl_param_list: /* specific to lint */ abstract_decl_lparen T_RPAREN type_attribute_list_opt { $$ = (parameter_list){ .used = $3.used }; } | abstract_decl_lparen vararg_parameter_type_list T_RPAREN type_attribute_list_opt { $$ = $2; $$.prototype = true; $$.used = $4.used; $$.noreturn = $4.noreturn; } | abstract_decl_lparen error T_RPAREN type_attribute_list_opt { $$ = (parameter_list){ .used = $4.used }; } ; abstract_decl_lparen: /* specific to lint */ T_LPAREN { block_level++; begin_declaration_level(DLK_PROTO_PARAMS); } ; vararg_parameter_type_list: /* specific to lint */ parameter_type_list | parameter_type_list T_COMMA T_ELLIPSIS { $$ = $1; $$.vararg = true; } | T_ELLIPSIS { /* TODO: C99 6.7.5 makes this an error as well. */ if (!allow_trad && !allow_c99) /* C90 to C17 require formal parameter before '...' */ error(84); else if (allow_c90) /* C90 to C17 require formal parameter before '...' */ warning(84); $$ = (parameter_list){ .vararg = true }; } ; /* XXX: C99 6.7.5 defines the same name, but it looks different. */ parameter_type_list: parameter_declaration { $$ = (parameter_list){ .first = $1 }; } | parameter_type_list T_COMMA parameter_declaration { $$ = $1; $$.first = concat_symbols($1.first, $3); } ; /* K&R 8.7, C90 ???, C99 6.7.6, C11 6.7.7, C23 6.7.8 */ /* In K&R, abstract-declarator could be empty and was still simpler. */ abstract_declarator: pointer { $$ = add_pointer(abstract_name(), $1); } | direct_abstract_declarator | pointer direct_abstract_declarator { $$ = add_pointer($2, $1); } | type_attribute_list direct_abstract_declarator { $$ = $2; } | pointer type_attribute_list direct_abstract_declarator { $$ = add_pointer($3, $1); } ; /* K&R ---, C90 ???, C99 6.7.6, C11 6.7.7, C23 6.7.8 */ direct_abstract_declarator: /* TODO: sort rules according to C99 */ T_LPAREN abstract_declarator T_RPAREN { $$ = $2; } | T_LBRACK array_size_opt T_RBRACK { $$ = add_array(abstract_name(), $2.has_dim, $2.dim); } | direct_abstract_declarator T_LBRACK array_size_opt T_RBRACK { $$ = add_array($1, $3.has_dim, $3.dim); } | abstract_decl_param_list asm_or_symbolrename_opt { sym_t *name = abstract_enclosing_name(); $$ = add_function(symbolrename(name, $2), $1); end_declaration_level(); block_level--; } | direct_abstract_declarator abstract_decl_param_list asm_or_symbolrename_opt { $$ = add_function(symbolrename($1, $3), $2); end_declaration_level(); block_level--; } | direct_abstract_declarator type_attribute_list ; /* TODO: Implement 'array_abstract_declarator' from C23 6.7.8. */ /* TODO: Implement 'function_abstract_declarator' from C23 6.7.8. */ /* TODO: Implement 'typedef_name' from C23 6.7.9. */ /* C23 6.7.11 */ /* K&R ---, C90 ---, C99 6.7.8, C11 6.7.9, C23 6.7.10 */ braced_initializer: init_lbrace init_rbrace { /* empty initializer braces require C23 or later */ c23ism(353); } | init_lbrace initializer_list init_rbrace | init_lbrace initializer_list T_COMMA init_rbrace ; /* C99 6.7.8, C23 6.7.11 */ initializer: assignment_expression { init_expr($1); } | init_lbrace init_rbrace { /* XXX: Empty braces are not covered by C99 6.7.8. */ } | init_lbrace initializer_list init_rbrace | init_lbrace initializer_list T_COMMA init_rbrace /* XXX: What is this error handling for? */ | error ; /* C99 6.7.8, C23 6.7.11 */ initializer_list: initializer | designation initializer | initializer_list T_COMMA initializer | initializer_list T_COMMA designation initializer ; /* C99 6.7.8, C23 6.7.11 */ designation: { begin_designation(); } designator_list T_ASSIGN | identifier T_COLON { /* GCC style struct or union member name in initializer */ gnuism(315); begin_designation(); add_designator_member($1); } ; /* C99 6.7.8, C23 6.7.11 */ designator_list: designator | designator_list designator ; /* C99 6.7.8, C23 6.7.11 */ designator: T_LBRACK range T_RBRACK { if (!allow_c99) /* array initializer with designators is a C99 ... */ warning(321); add_designator_subscript($2); } | T_POINT identifier { if (!allow_c99) /* struct or union member name in initializer is ... */ warning(313); add_designator_member($2); } ; /* C23 6.7.12 */ static_assert_declaration: T_STATIC_ASSERT T_LPAREN constant_expression T_COMMA T_STRING T_RPAREN T_SEMI { /* '_Static_assert' requires C11 or later */ c11ism(354); } | T_STATIC_ASSERT T_LPAREN constant_expression T_RPAREN T_SEMI { /* '_Static_assert' without message requires C23 or later */ c23ism(355); } ; range: constant_expression { $$.lo = to_int_constant($1, true); $$.hi = $$.lo; } | constant_expression T_ELLIPSIS constant_expression { $$.lo = to_int_constant($1, true); $$.hi = to_int_constant($3, true); /* initialization with '[a...b]' is a GCC extension */ gnuism(340); } ; init_lbrace: /* helper */ T_LBRACE { init_lbrace(); } ; init_rbrace: /* helper */ T_RBRACE { init_rbrace(); } ; /* C23 6.7.13.2 */ attribute_specifier_sequence: attribute_specifier { $$ = (attribute_list) { NULL, 0, 0 }; attribute_list_add_all(&$$, $1); } | attribute_specifier_sequence attribute_specifier { $$ = $1; attribute_list_add_all(&$$, $2); } ; /* C23 6.7.13.2 */ attribute_specifier: T_LBRACK T_LBRACK attribute_list T_RBRACK T_RBRACK { $$ = $3; } ; /* C23 6.7.13.2 */ attribute_list: /* empty */ { $$ = (attribute_list) { NULL, 0, 0 }; } | attribute { $$ = (attribute_list) { NULL, 0, 0 }; attribute_list_add(&$$, $1); } | attribute_list T_COMMA | attribute_list T_COMMA attribute { $$ = $1; attribute_list_add(&$$, $3); } ; /* C23 6.7.13.2 */ attribute: identifier { $$ = new_attribute(NULL, $1, NULL); } | identifier T_DCOLON identifier { $$ = new_attribute($1, $3, NULL); } | identifier attribute_argument_clause { $$ = new_attribute(NULL, $1, &$2); } | identifier T_DCOLON identifier attribute_argument_clause { $$ = new_attribute($1, $3, &$4); } ; /* The rule 'attribute_token' is inlined into 'attribute'. */ /* The rule 'standard_attribute' is inlined into 'attribute_token'. */ /* The rule 'attribute_prefixed_token' is inlined into 'attribute_token'. */ /* The rule 'attribute_prefix' is inlined into 'attribute_token'. */ /* C23 6.7.13.2 */ attribute_argument_clause: T_LPAREN { $$ = read_balanced_token_sequence(); } ; /* The rule 'balanced_token_sequence' is inlined into 'attribute_argument_clause'. */ /* The rule 'balanced_token' is inlined into 'balanced_token_sequence'. */ asm_or_symbolrename_opt: /* GCC extensions */ /* empty */ { $$ = NULL; } | T_ASM T_LPAREN T_STRING T_RPAREN gcc_attribute_specifier_list_opt { freeyyv(&$3, T_STRING); $$ = NULL; } | T_SYMBOLRENAME T_LPAREN T_NAME T_RPAREN gcc_attribute_specifier_list_opt { $$ = $3; } ; /* K&R ???, C90 ???, C99 6.8, C11 ???, C23 6.8.1 */ statement: expression_statement | non_expr_statement ; /* Helper to avoid shift/reduce conflict in 'label: __attribute__ ;'. */ no_attr_statement: expression_statement | no_attr_non_expr_statement ; non_expr_statement: /* helper for C99 6.8 */ gcc_attribute_specifier /* ((__fallthrough__)) */ T_SEMI | no_attr_non_expr_statement ; /* Helper to avoid shift/reduce conflict in 'label: __attribute__ ;'. */ no_attr_non_expr_statement: labeled_statement | compound_statement | selection_statement | iteration_statement | jump_statement { suppress_fallthrough = false; } | asm_statement ; /* TODO: Implement 'unlabeled_statement' from C23 6.8.1. */ /* TODO: Implement 'primary_block' from C23 6.8.1. */ /* TODO: Implement 'secondary_block' from C23 6.8.1. */ /* C23 6.8.2 */ label: T_NAME T_COLON { set_sym_kind(SK_LABEL); named_label(getsym($1)); } | T_CASE constant_expression T_COLON { case_label($2); suppress_fallthrough = true; } | T_CASE constant_expression T_ELLIPSIS constant_expression T_COLON { /* XXX: We don't fill all cases */ case_label($2); suppress_fallthrough = true; } | T_DEFAULT T_COLON { default_label(); suppress_fallthrough = true; } ; /* C99 6.8.1, C23 6.8.2 */ labeled_statement: label gcc_attribute_specifier_list_opt no_attr_statement ; /* C99 6.8.2, C23 6.8.3 */ compound_statement: compound_statement_lbrace compound_statement_rbrace | compound_statement_lbrace block_item_list compound_statement_rbrace ; compound_statement_lbrace: T_LBRACE { block_level++; mem_block_level++; debug_step("%s: mem_block_level = %zu", "compound_statement_lbrace", mem_block_level); begin_declaration_level(DLK_AUTO); } ; compound_statement_rbrace: T_RBRACE { end_declaration_level(); if (!in_statement_expr()) level_free_all(mem_block_level); /* leak */ mem_block_level--; debug_step("%s: mem_block_level = %zu", "compound_statement_rbrace", mem_block_level); block_level--; suppress_fallthrough = false; } ; /* C99 6.8.2, C23 6.8.3 */ block_item_list: block_item | block_item_list block_item { if ($1 && !$2) /* declarations after statements is a C99 feature */ c99ism(327); $$ = $1 || $2; } ; /* C99 6.8.2, C23 6.8.3 */ block_item: declaration_or_error { $$ = false; restore_warning_flags(); } | statement { $$ = true; restore_warning_flags(); } ; /* C99 6.8.3, C23 6.8.4 */ expression_statement: expression T_SEMI { /* * Even though a "call statement" is not a formally defined * term in the C standards, it occurs so often that it's * helpful to have a distinguishable term for it. */ expr($1, false, false, false, false, $1 != NULL && $1->tn_op == CALL ? "call" : "expression"); suppress_fallthrough = false; if ($1 != NULL && $1->tn_op == CALL && $1->u.call->func->tn_type->t_subt->t_noreturn) stmt_call_noreturn(); } | T_SEMI { check_statement_reachable("empty"); suppress_fallthrough = false; } | attribute_specifier_sequence expression T_SEMI { debug_attribute_list(&$1); /* * Even though a "call statement" is not a formally defined * term in the C standards, it occurs so often that it's * helpful to have a distinguishable term for it. */ expr($2, false, false, false, false, $2 != NULL && $2->tn_op == CALL ? "call" : "expression"); suppress_fallthrough = false; } | attribute_specifier_sequence T_SEMI { bool is_fallthrough = attributes_contain(&$1, "fallthrough"); debug_attribute_list(&$1); check_statement_reachable( is_fallthrough ? "fallthrough" : "empty"); suppress_fallthrough = is_fallthrough; } ; /* C99 6.8.4, C23 6.8.5.1 */ selection_statement: if_without_else %prec T_THEN { save_warning_flags(); stmt_if_then_stmt(); stmt_if_else_stmt(false); } | if_without_else T_ELSE { save_warning_flags(); stmt_if_then_stmt(); } statement { restore_warning_flags(); stmt_if_else_stmt(true); } | if_without_else T_ELSE error { clear_warning_flags(); stmt_if_else_stmt(false); } | switch_expr statement { clear_warning_flags(); stmt_switch_expr_stmt(); } | switch_expr error { clear_warning_flags(); stmt_switch_expr_stmt(); } ; if_without_else: /* see C99 6.8.4 */ if_expr statement | if_expr error ; if_expr: /* see C99 6.8.4 */ T_IF T_LPAREN expression T_RPAREN { stmt_if_expr($3); clear_warning_flags(); } ; switch_expr: /* see C99 6.8.4 */ T_SWITCH T_LPAREN expression T_RPAREN { stmt_switch_expr($3); clear_warning_flags(); } ; /* C99 6.8.5, C23 6.8.6.1 */ iteration_statement: while_expr statement { clear_warning_flags(); stmt_while_expr_stmt(); } | while_expr error { clear_warning_flags(); stmt_while_expr_stmt(); } | do_statement T_WHILE T_LPAREN expression T_RPAREN T_SEMI { stmt_do_while_expr($4); suppress_fallthrough = false; } | do error { clear_warning_flags(); stmt_do_while_expr(NULL); } | for_exprs statement { clear_warning_flags(); stmt_for_exprs_stmt(); end_declaration_level(); block_level--; } | for_exprs error { clear_warning_flags(); stmt_for_exprs_stmt(); end_declaration_level(); block_level--; } ; while_expr: /* see C99 6.8.5 */ T_WHILE T_LPAREN expression T_RPAREN { stmt_while_expr($3); clear_warning_flags(); } ; do_statement: /* see C99 6.8.5 */ do statement { clear_warning_flags(); } ; do: /* see C99 6.8.5 */ T_DO { stmt_do(); } ; for_start: /* see C99 6.8.5 */ T_FOR T_LPAREN { begin_declaration_level(DLK_AUTO); block_level++; } ; for_exprs: /* see C99 6.8.5 */ for_start begin_type_declaration_specifiers end_type notype_init_declarator_list T_SEMI expression_opt T_SEMI expression_opt T_RPAREN { /* variable declaration in for loop */ c99ism(325); stmt_for_exprs(NULL, $6, $8); clear_warning_flags(); } | for_start expression_opt T_SEMI expression_opt T_SEMI expression_opt T_RPAREN { stmt_for_exprs($2, $4, $6); clear_warning_flags(); } ; /* C99 6.8.6, C23 6.8.7.1 */ jump_statement: goto identifier T_SEMI { stmt_goto(getsym($2)); } | goto error T_SEMI { set_sym_kind(SK_VCFT); } | T_CONTINUE T_SEMI { stmt_continue(); } | T_BREAK T_SEMI { stmt_break(); } | T_RETURN sys T_SEMI { stmt_return($2, NULL); } | T_RETURN sys expression T_SEMI { stmt_return($2, $3); } ; goto: /* see C99 6.8.6 */ T_GOTO { set_sym_kind(SK_LABEL); } ; asm_statement: /* GCC extension */ T_ASM T_LPAREN read_until_rparen T_SEMI { dcs_set_asm(); } | T_ASM type_qualifier T_LPAREN read_until_rparen T_SEMI { dcs_set_asm(); } | T_ASM error ; read_until_rparen: /* helper for 'asm_statement' */ /* empty */ { read_until_rparen(); } ; /* C99 6.9, C23 6.9.1 */ translation_unit: external_declaration | translation_unit external_declaration ; /* C99 6.9, C23 6.9.1 */ external_declaration: function_definition { global_clean_up_decl(false); clear_warning_flags(); } | top_level_declaration { global_clean_up_decl(false); clear_warning_flags(); } | asm_statement /* GCC extension */ | T_SEMI { /* GCC extension */ /* * TODO: Only allow this in GCC mode, not in plain C99. * This is one of the top 10 warnings in the NetBSD build. */ if (!allow_trad && !allow_c99) /* empty declaration */ error(0); else if (allow_c90) /* empty declaration */ warning(0); } ; /* * On the top level, lint allows several forms of declarations that it doesn't * allow in functions. For example, a single ';' is an empty declaration and * is supported by some compilers, but in a function it would be an empty * statement, not a declaration. This makes a difference in C90 mode, where * a statement must not be followed by a declaration. * * See 'declaration' for all other declarations. */ top_level_declaration: /* C99 6.9 calls this 'declaration' */ begin_type end_type notype_init_declarator_list T_SEMI { /* TODO: Make this an error in C99 mode as well. */ if (!allow_trad && !allow_c99) /* old-style declaration; add 'int' */ error(1); else if (allow_c90) /* old-style declaration; add 'int' */ warning(1); } | declaration | error T_SEMI { global_clean_up(); } | error T_RBRACE { global_clean_up(); } ; /* C99 6.9.1, C23 6.9.2 */ function_definition: func_declarator { if ($1->s_type->t_tspec != FUNC) { /* syntax error '%s' */ error(249, yytext); YYERROR; } if ($1->s_type->t_typedef) { /* ()-less function definition */ error(64); YYERROR; } check_extern_declaration($1); begin_function($1); block_level++; begin_declaration_level(DLK_OLD_STYLE_PARAMS); if (lwarn == LWARN_NONE) $1->s_used = true; } arg_declaration_list_opt { end_declaration_level(); block_level--; check_func_lint_directives(); check_func_old_style_parameters(); begin_control_statement(CS_FUNCTION_BODY); } compound_statement { end_function(); end_control_statement(CS_FUNCTION_BODY); } ; func_declarator: begin_type end_type notype_declarator { if (!allow_trad) /* old-style declaration; add 'int' */ error(1); $$ = $3; } | begin_type_declmods end_type notype_declarator { if (!allow_trad) /* old-style declaration; add 'int' */ error(1); $$ = $3; } | begin_type_declaration_specifiers end_type type_declarator { $$ = $3; } ; arg_declaration_list_opt: /* C99 6.9.1p13 example 1 */ /* empty */ | arg_declaration_list ; arg_declaration_list: /* C99 6.9.1p13 example 1 */ arg_declaration | arg_declaration_list arg_declaration /* XXX or better "arg_declaration error" ? */ | error ; /* * "arg_declaration" is separated from "declaration" because it * needs other error handling. */ arg_declaration: begin_type_declmods end_type T_SEMI { /* empty declaration */ warning(2); } | begin_type_declmods end_type notype_init_declarator_list T_SEMI | begin_type_declaration_specifiers end_type T_SEMI { if (!dcs->d_nonempty_decl) /* empty declaration */ warning(2); else /* '%s' declared in parameter declaration list */ warning(3, type_name(dcs->d_type)); } | begin_type_declaration_specifiers end_type type_init_declarator_list T_SEMI { if (dcs->d_nonempty_decl) /* '%s' declared in parameter declaration list */ warning(3, type_name(dcs->d_type)); } | begin_type_declmods error | begin_type_declaration_specifiers error ; /* https://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html */ gcc_attribute_specifier_list_opt: /* empty */ { $$ = (type_attributes){ .used = false }; } | gcc_attribute_specifier_list ; gcc_attribute_specifier_list: gcc_attribute_specifier | gcc_attribute_specifier_list gcc_attribute_specifier { $$ = (type_attributes){ .used = $1.used || $2.used }; } ; gcc_attribute_specifier: T_ATTRIBUTE T_LPAREN T_LPAREN { in_gcc_attribute = true; } gcc_attribute_list { in_gcc_attribute = false; } T_RPAREN T_RPAREN { $$ = $5; } ; gcc_attribute_list: gcc_attribute | gcc_attribute_list T_COMMA gcc_attribute { $$ = (type_attributes){ .used = $1.used || $3.used }; } ; gcc_attribute: /* empty */ { $$ = (type_attributes){ .used = false }; } | T_NAME { $$ = (type_attributes){ .used = false }; const char *name = $1->sb_name; if (is_either(name, "packed", "__packed__")) dcs_add_packed(); else if (is_either(name, "used", "__used__") || is_either(name, "constructor", "__constructor__") || is_either(name, "unused", "__unused__")) $$.used = true; else if (is_either(name, "fallthrough", "__fallthrough__")) suppress_fallthrough = true; else if (is_either(name, "noreturn", "__noreturn__")) $$.noreturn = true; } | T_NAME T_LPAREN T_RPAREN { $$ = (type_attributes){ .used = false }; } | T_NAME T_LPAREN argument_expression_list T_RPAREN { const char *name = $1->sb_name; if (is_either(name, "aligned", "__aligned__") && $3->args_len == 1) dcs_add_alignas($3->args[0]); $$ = (type_attributes){ .used = false }; } | type_qualifier { if (!$1.tq_const) yyerror("Bad attribute"); $$ = (type_attributes){ .used = false }; } ; /* The rule 'function_body' from C23 6.9.2 is inlined into 'function_definition'. */ sys: /* empty */ { $$ = in_system_header; } ; %% /* ARGSUSED */ int yyerror(const char *msg) { /* syntax error '%s' */ error(249, yytext); if (++sytxerr >= 5) norecover(); return 0; } #if YYDEBUG && YYBYACC static const char * cgram_to_string(int tok, YYSTYPE val) { switch (tok) { case T_INCDEC: return val.y_inc ? "++" : "--"; case T_MULTIPLICATIVE: case T_ADDITIVE: case T_SHIFT: case T_RELATIONAL: case T_EQUALITY: case T_OPASSIGN: return op_name(val.y_op); case T_SCLASS: return scl_name(val.y_scl); case T_TYPE: case T_STRUCT_OR_UNION: return tspec_name(val.y_tspec); case T_QUAL: return type_qualifiers_string(val.y_type_qualifiers); case T_FUNCTION_SPECIFIER: return function_specifier_name(val.y_function_specifier); case T_NAME: return val.y_name->sb_name; default: return ""; } } #endif static void cgram_declare(sym_t *decl, bool has_initializer, sbuf_t *renaming) { declare(decl, has_initializer, renaming); if (renaming != NULL) freeyyv(&renaming, T_NAME); } /* * Discard all input tokens up to and including the next unmatched right * parenthesis. */ static void read_until_rparen(void) { int level; if (yychar < 0) yychar = yylex(); freeyyv(&yylval, yychar); level = 1; while (yychar > 0) { if (yychar == T_LPAREN) level++; if (yychar == T_RPAREN && --level == 0) break; freeyyv(&yylval, yychar = yylex()); } yyclearin; } static balanced_token_sequence read_balanced_token_sequence(void) { lint_assert(yychar < 0); balanced_token_sequence seq = lex_balanced(); yyclearin; return seq; } static sym_t * symbolrename(sym_t *s, sbuf_t *sb) { if (sb != NULL) s->s_rename = sb->sb_name; return s; }