1/* $NetBSD: ckbool.c,v 1.32 2024/05/12 12:32:39 rillig Exp $ */ 2 3/*- 4 * Copyright (c) 2021 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Roland Illig <rillig@NetBSD.org>. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32#if HAVE_NBTOOL_CONFIG_H 33#include "nbtool_config.h" 34#endif 35 36#include <sys/cdefs.h> 37 38#if defined(__RCSID) 39__RCSID("$NetBSD: ckbool.c,v 1.32 2024/05/12 12:32:39 rillig Exp $"); 40#endif 41 42#include <string.h> 43 44#include "lint1.h" 45 46 47/* 48 * The option -T treats _Bool as incompatible with all other scalar types. 49 * See d_c99_bool_strict.c for the detailed rules and for examples. 50 */ 51 52 53static bool 54is_int_constant_zero(const tnode_t *tn, tspec_t t) 55{ 56 return t == INT && tn->tn_op == CON && tn->u.value.u.integer == 0; 57} 58 59static bool 60is_typeok_strict_bool_binary(op_t op, 61 const tnode_t *ln, tspec_t lt, 62 const tnode_t *rn, tspec_t rt) 63{ 64 if ((lt == BOOL) == (rt == BOOL)) 65 return true; 66 67 if (op == FARG && rn->tn_sys) 68 return false; 69 70 if ((ln->tn_sys || rn->tn_sys) && 71 (is_int_constant_zero(ln, lt) || is_int_constant_zero(rn, rt))) 72 return true; 73 74 if (op == ASSIGN || op == ANDASS || op == XORASS || op == ORASS || 75 op == RETURN || op == INIT || op == FARG) 76 return lt != BOOL && (ln->tn_sys || rn->tn_sys); 77 78 if (op == EQ || op == NE || 79 op == BITAND || op == BITXOR || op == BITOR || 80 op == COLON) 81 return false; 82 83 return true; 84} 85 86/* 87 * Some operators require that either both operands are bool or both are 88 * scalar. 89 * 90 * Code that passes this check can be compiled in a pre-C99 environment that 91 * doesn't implement the special rule C99 6.3.1.2, without silent change in 92 * behavior. 93 */ 94static bool 95typeok_strict_bool_binary_compatible(op_t op, int arg, 96 const tnode_t *ln, tspec_t lt, 97 const tnode_t *rn, tspec_t rt) 98{ 99 if (is_typeok_strict_bool_binary(op, ln, lt, rn, rt)) 100 return true; 101 102 if (op == FARG) 103 /* parameter %d expects '%s', gets passed '%s' */ 104 error(334, arg, tspec_name(lt), tspec_name(rt)); 105 else if (op == RETURN) 106 /* function has return type '%s' but returns '%s' */ 107 error(211, tspec_name(lt), tspec_name(rt)); 108 else 109 /* operands of '%s' have incompatible types '%s' and '%s' */ 110 error(107, op_name(op), tspec_name(lt), tspec_name(rt)); 111 112 return false; 113} 114 115/* 116 * In strict bool mode, check whether the types of the operands match the 117 * operator. 118 */ 119bool 120typeok_scalar_strict_bool(op_t op, const mod_t *mp, int arg, 121 const tnode_t *ln, 122 const tnode_t *rn) 123{ 124 ln = before_conversion(ln); 125 tspec_t lt = ln->tn_type->t_tspec; 126 tspec_t rt = NO_TSPEC; 127 if (rn != NULL) { 128 rn = before_conversion(rn); 129 rt = rn->tn_type->t_tspec; 130 } 131 132 if (rn != NULL && 133 !typeok_strict_bool_binary_compatible(op, arg, ln, lt, rn, rt)) 134 return false; 135 136 if (mp->m_compares_with_zero) { 137 bool binary = mp->m_binary; 138 bool lbool = is_typeok_bool_compares_with_zero(ln, false); 139 bool ok = true; 140 141 if (!binary && !lbool) { 142 /* operand of '%s' must be bool, not '%s' */ 143 error(330, op_name(op), tspec_name(lt)); 144 ok = false; 145 } 146 if (binary && !lbool) { 147 /* left operand of '%s' must be bool, not '%s' */ 148 error(331, op_name(op), tspec_name(lt)); 149 ok = false; 150 } 151 if (binary && op != QUEST && 152 !is_typeok_bool_compares_with_zero(rn, false)) { 153 /* right operand of '%s' must be bool, not '%s' */ 154 error(332, op_name(op), tspec_name(rt)); 155 ok = false; 156 } 157 return ok; 158 } 159 160 if (!mp->m_takes_bool) { 161 bool binary = mp->m_binary; 162 bool lbool = lt == BOOL; 163 bool ok = true; 164 165 if (!binary && lbool) { 166 /* operand of '%s' must not be bool */ 167 error(335, op_name(op)); 168 ok = false; 169 } 170 if (binary && lbool) { 171 /* left operand of '%s' must not be bool */ 172 error(336, op_name(op)); 173 ok = false; 174 } 175 if (binary && rt == BOOL) { 176 /* right operand of '%s' must not be bool */ 177 error(337, op_name(op)); 178 ok = false; 179 } 180 return ok; 181 } 182 183 return true; 184} 185 186bool 187is_typeok_bool_compares_with_zero(const tnode_t *tn, bool is_do_while) 188{ 189 while (tn->tn_op == COMMA) 190 tn = tn->u.ops.right; 191 tn = before_conversion(tn); 192 193 return tn->tn_type->t_tspec == BOOL 194 || tn->tn_op == BITAND 195 || (is_do_while && is_int_constant_zero(tn, tn->tn_type->t_tspec)) 196 || (tn->tn_sys && is_scalar(tn->tn_type->t_tspec)); 197} 198 199bool 200fallback_symbol_strict_bool(sym_t *sym) 201{ 202 if (strcmp(sym->s_name, "__lint_false") == 0) { 203 sym->s_scl = BOOL_CONST; 204 sym->s_type = gettyp(BOOL); 205 sym->u.s_bool_constant = false; 206 return true; 207 } 208 209 if (strcmp(sym->s_name, "__lint_true") == 0) { 210 sym->s_scl = BOOL_CONST; 211 sym->s_type = gettyp(BOOL); 212 sym->u.s_bool_constant = true; 213 return true; 214 } 215 216 return false; 217} 218