ckbool.c revision 1.27
1 /* $NetBSD: ckbool.c,v 1.27 2023/12/03 12:03:38 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 (at) 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 1.27 2023/12/03 12:03:38 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 exact rules and for examples. 50 */ 51 52 53 /* 54 * See if in strict bool mode, the operator takes either two bool operands 55 * or two arbitrary other operands. 56 */ 57 static bool 58 is_assignment_bool_or_other(op_t op) 59 { 60 return op == ASSIGN || 61 op == ANDASS || op == XORASS || op == ORASS || 62 op == RETURN || op == INIT || op == FARG; 63 } 64 65 static bool 66 is_symmetric_bool_or_other(op_t op) 67 { 68 return op == EQ || op == NE || 69 op == BITAND || op == BITXOR || op == BITOR || 70 op == COLON; 71 } 72 73 static bool 74 is_int_constant_zero(const tnode_t *tn, tspec_t t) 75 { 76 return t == INT && tn->tn_op == CON && tn->tn_val.u.integer == 0; 77 } 78 79 static bool 80 is_typeok_strict_bool_binary(op_t op, 81 const tnode_t *ln, tspec_t lt, 82 const tnode_t *rn, tspec_t rt) 83 { 84 if ((lt == BOOL) == (rt == BOOL)) 85 return true; 86 87 if (op == FARG && rn->tn_sys) 88 return false; 89 90 if ((ln->tn_sys || rn->tn_sys) && 91 (is_int_constant_zero(ln, lt) || is_int_constant_zero(rn, rt))) 92 return true; 93 94 if (is_assignment_bool_or_other(op)) 95 return lt != BOOL && (ln->tn_sys || rn->tn_sys); 96 97 return !is_symmetric_bool_or_other(op); 98 } 99 100 /* 101 * Some operators require that either both operands are bool or both are 102 * scalar. 103 * 104 * Code that passes this check can be compiled in a pre-C99 environment that 105 * doesn't implement the special rule C99 6.3.1.2, without silent change in 106 * behavior. 107 */ 108 static bool 109 typeok_strict_bool_binary_compatible(op_t op, int arg, 110 const tnode_t *ln, tspec_t lt, 111 const tnode_t *rn, tspec_t rt) 112 { 113 if (is_typeok_strict_bool_binary(op, ln, lt, rn, rt)) 114 return true; 115 116 if (op == FARG) { 117 /* parameter %d expects '%s', gets passed '%s' */ 118 error(334, arg, tspec_name(lt), tspec_name(rt)); 119 } else if (op == RETURN) { 120 /* function has return type '%s' but returns '%s' */ 121 error(211, tspec_name(lt), tspec_name(rt)); 122 } else { 123 /* operands of '%s' have incompatible types '%s' and '%s' */ 124 error(107, op_name(op), tspec_name(lt), tspec_name(rt)); 125 } 126 127 return false; 128 } 129 130 /* 131 * In strict bool mode, check whether the types of the operands match the 132 * operator. 133 */ 134 bool 135 typeok_scalar_strict_bool(op_t op, const mod_t *mp, int arg, 136 const tnode_t *ln, 137 const tnode_t *rn) 138 { 139 tspec_t lt, rt; 140 141 ln = before_conversion(ln); 142 lt = ln->tn_type->t_tspec; 143 144 if (rn != NULL) { 145 rn = before_conversion(rn); 146 rt = rn->tn_type->t_tspec; 147 } else { 148 rt = NO_TSPEC; 149 } 150 151 if (rn != NULL && 152 !typeok_strict_bool_binary_compatible(op, arg, ln, lt, rn, rt)) 153 return false; 154 155 if (mp->m_compares_with_zero) { 156 bool binary = mp->m_binary; 157 bool lbool = is_typeok_bool_compares_with_zero(ln); 158 bool ok = true; 159 160 if (!binary && !lbool) { 161 /* operand of '%s' must be bool, not '%s' */ 162 error(330, op_name(op), tspec_name(lt)); 163 ok = false; 164 } 165 if (binary && !lbool) { 166 /* left operand of '%s' must be bool, not '%s' */ 167 error(331, op_name(op), tspec_name(lt)); 168 ok = false; 169 } 170 if (binary && op != QUEST && 171 !is_typeok_bool_compares_with_zero(rn)) { 172 /* right operand of '%s' must be bool, not '%s' */ 173 error(332, op_name(op), tspec_name(rt)); 174 ok = false; 175 } 176 return ok; 177 } 178 179 if (!mp->m_takes_bool) { 180 bool binary = mp->m_binary; 181 bool lbool = lt == BOOL; 182 bool ok = true; 183 184 if (!binary && lbool) { 185 /* operand of '%s' must not be bool */ 186 error(335, op_name(op)); 187 ok = false; 188 } 189 if (binary && lbool) { 190 /* left operand of '%s' must not be bool */ 191 error(336, op_name(op)); 192 ok = false; 193 } 194 if (binary && rt == BOOL) { 195 /* right operand of '%s' must not be bool */ 196 error(337, op_name(op)); 197 ok = false; 198 } 199 return ok; 200 } 201 202 return true; 203 } 204 205 /* 206 * See if the node is valid as operand of an operator that compares its 207 * operand with 0. 208 */ 209 bool 210 is_typeok_bool_compares_with_zero(const tnode_t *tn) 211 { 212 tspec_t t; 213 214 while (tn->tn_op == COMMA) 215 tn = tn->tn_right; 216 tn = before_conversion(tn); 217 t = tn->tn_type->t_tspec; 218 219 if (t == BOOL) 220 return true; 221 222 if (tn->tn_sys && is_scalar(t)) 223 return true; 224 225 /* For enums that are used as bit sets, allow "flags & FLAG". */ 226 if (tn->tn_op == BITAND && 227 tn->tn_left->tn_op == CVT && 228 tn->tn_left->tn_type->t_is_enum && 229 tn->tn_right->tn_type->t_is_enum) 230 return true; 231 232 return false; 233 } 234 235 bool 236 fallback_symbol_strict_bool(sym_t *sym) 237 { 238 if (strcmp(sym->s_name, "__lint_false") == 0) { 239 sym->s_scl = BOOL_CONST; 240 sym->s_type = gettyp(BOOL); 241 sym->u.s_bool_constant = false; 242 return true; 243 } 244 245 if (strcmp(sym->s_name, "__lint_true") == 0) { 246 sym->s_scl = BOOL_CONST; 247 sym->s_type = gettyp(BOOL); 248 sym->u.s_bool_constant = true; 249 return true; 250 } 251 252 return false; 253 } 254
Indexes created Tue Oct 14 11:09:46 GMT 2025