ckbool.c revision 1.20
1 /* $NetBSD: ckbool.c,v 1.20 2023/01/21 20:07:01 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 1.20 2023/01/21 20:07:01 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 static const char * 54 op_name(op_t op) 55 { 56 return modtab[op].m_name; 57 } 58 59 /* 60 * See if in strict bool mode, the operator takes either two bool operands 61 * or two arbitrary other operands. 62 */ 63 static bool 64 is_assignment_bool_or_other(op_t op) 65 { 66 return op == ASSIGN || 67 op == ANDASS || op == XORASS || op == ORASS || 68 op == RETURN || op == INIT || op == FARG; 69 } 70 71 static bool 72 is_symmetric_bool_or_other(op_t op) 73 { 74 return op == EQ || op == NE || 75 op == BITAND || op == BITXOR || op == BITOR || 76 op == COLON; 77 } 78 79 static bool 80 is_int_constant_zero(const tnode_t *tn, tspec_t t) 81 { 82 return t == INT && tn->tn_op == CON && tn->tn_val->v_quad == 0; 83 } 84 85 static bool 86 is_typeok_strict_bool_binary(op_t op, 87 const tnode_t *ln, tspec_t lt, 88 const tnode_t *rn, tspec_t rt) 89 { 90 if ((lt == BOOL) == (rt == BOOL)) 91 return true; 92 93 if (op == FARG && rn->tn_sys) 94 return false; 95 96 if ((ln->tn_sys || rn->tn_sys) && 97 (is_int_constant_zero(ln, lt) || is_int_constant_zero(rn, rt))) 98 return true; 99 100 if (is_assignment_bool_or_other(op)) 101 return lt != BOOL && (ln->tn_sys || rn->tn_sys); 102 103 return !is_symmetric_bool_or_other(op); 104 } 105 106 /* 107 * Some operators require that either both operands are bool or both are 108 * scalar. 109 * 110 * Code that passes this check can be compiled in a pre-C99 environment that 111 * doesn't implement the special rule C99 6.3.1.2, without silent change in 112 * behavior. 113 */ 114 static bool 115 typeok_strict_bool_binary_compatible(op_t op, int arg, 116 const tnode_t *ln, tspec_t lt, 117 const tnode_t *rn, tspec_t rt) 118 { 119 if (is_typeok_strict_bool_binary(op, ln, lt, rn, rt)) 120 return true; 121 122 if (op == FARG) { 123 /* argument #%d expects '%s', gets passed '%s' */ 124 error(334, arg, tspec_name(lt), tspec_name(rt)); 125 } else if (op == RETURN) { 126 /* function has return type '%s' but returns '%s' */ 127 error(211, tspec_name(lt), tspec_name(rt)); 128 } else { 129 /* operands of '%s' have incompatible types '%s' and '%s' */ 130 error(107, op_name(op), tspec_name(lt), tspec_name(rt)); 131 } 132 133 return false; 134 } 135 136 /* 137 * In strict bool mode, check whether the types of the operands match the 138 * operator. 139 */ 140 bool 141 typeok_scalar_strict_bool(op_t op, const mod_t *mp, int arg, 142 const tnode_t *ln, 143 const tnode_t *rn) 144 { 145 tspec_t lt, rt; 146 147 ln = before_conversion(ln); 148 lt = ln->tn_type->t_tspec; 149 150 if (rn != NULL) { 151 rn = before_conversion(rn); 152 rt = rn->tn_type->t_tspec; 153 } else { 154 rt = NOTSPEC; 155 } 156 157 if (rn != NULL && 158 !typeok_strict_bool_binary_compatible(op, arg, ln, lt, rn, rt)) 159 return false; 160 161 if (mp->m_compares_with_zero) { 162 bool binary = mp->m_binary; 163 bool lbool = is_typeok_bool_compares_with_zero(ln); 164 bool ok = true; 165 166 if (!binary && !lbool) { 167 /* operand of '%s' must be bool, not '%s' */ 168 error(330, op_name(op), tspec_name(lt)); 169 ok = false; 170 } 171 if (binary && !lbool) { 172 /* left operand of '%s' must be bool, not '%s' */ 173 error(331, op_name(op), tspec_name(lt)); 174 ok = false; 175 } 176 if (binary && op != QUEST && 177 !is_typeok_bool_compares_with_zero(rn)) { 178 /* right operand of '%s' must be bool, not '%s' */ 179 error(332, op_name(op), tspec_name(rt)); 180 ok = false; 181 } 182 return ok; 183 } 184 185 if (!mp->m_takes_bool) { 186 bool binary = mp->m_binary; 187 bool lbool = lt == BOOL; 188 bool ok = true; 189 190 if (!binary && lbool) { 191 /* operand of '%s' must not be bool */ 192 error(335, op_name(op)); 193 ok = false; 194 } 195 if (binary && lbool) { 196 /* left operand of '%s' must not be bool */ 197 error(336, op_name(op)); 198 ok = false; 199 } 200 if (binary && rt == BOOL) { 201 /* right operand of '%s' must not be bool */ 202 error(337, op_name(op)); 203 ok = false; 204 } 205 return ok; 206 } 207 208 return true; 209 } 210 211 /* 212 * See if the node is valid as operand of an operator that compares its 213 * argument with 0. 214 */ 215 bool 216 is_typeok_bool_compares_with_zero(const tnode_t *tn) 217 { 218 tspec_t t; 219 220 while (tn->tn_op == COMMA) 221 tn = tn->tn_right; 222 tn = before_conversion(tn); 223 t = tn->tn_type->t_tspec; 224 225 if (t == BOOL) 226 return true; 227 228 if (tn->tn_sys && is_scalar(t)) 229 return true; 230 231 /* For enums that are used as bit sets, allow "flags & FLAG". */ 232 if (tn->tn_op == BITAND && 233 tn->tn_left->tn_op == CVT && 234 tn->tn_left->tn_type->t_is_enum && 235 tn->tn_right->tn_type->t_is_enum) 236 return true; 237 238 return false; 239 } 240 241 bool 242 fallback_symbol_strict_bool(sym_t *sym) 243 { 244 if (strcmp(sym->s_name, "__lint_false") == 0) { 245 sym->s_scl = BOOL_CONST; 246 sym->s_type = gettyp(BOOL); 247 sym->u.s_bool_constant = false; 248 return true; 249 } 250 251 if (strcmp(sym->s_name, "__lint_true") == 0) { 252 sym->s_scl = BOOL_CONST; 253 sym->s_type = gettyp(BOOL); 254 sym->u.s_bool_constant = true; 255 return true; 256 } 257 258 return false; 259 } 260
Indexes created Sat Sep 27 14:09:57 GMT 2025