/* $NetBSD: ckbool.c,v 1.19 2022/06/22 19:23:17 rillig Exp $ */ /*- * Copyright (c) 2021 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Roland Illig . * * 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. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``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 FOUNDATION OR CONTRIBUTORS * 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. */ #if HAVE_NBTOOL_CONFIG_H #include "nbtool_config.h" #endif #include #if defined(__RCSID) __RCSID("$NetBSD: ckbool.c,v 1.19 2022/06/22 19:23:17 rillig Exp $"); #endif #include #include "lint1.h" /* * The option -T treats _Bool as incompatible with all other scalar types. * See d_c99_bool_strict.c for the exact rules and for examples. */ static const char * op_name(op_t op) { return modtab[op].m_name; } /* * See if in strict bool mode, the operator takes either two bool operands * or two arbitrary other operands. */ static bool is_assignment_bool_or_other(op_t op) { return op == ASSIGN || op == ANDASS || op == XORASS || op == ORASS || op == RETURN || op == INIT || op == FARG; } static bool is_symmetric_bool_or_other(op_t op) { return op == EQ || op == NE || op == BITAND || op == BITXOR || op == BITOR || op == COLON; } static bool is_int_constant_zero(const tnode_t *tn, tspec_t t) { return t == INT && tn->tn_op == CON && tn->tn_val->v_quad == 0; } static bool is_typeok_strict_bool_binary(op_t op, const tnode_t *ln, tspec_t lt, const tnode_t *rn, tspec_t rt) { if ((lt == BOOL) == (rt == BOOL)) return true; if (op == FARG && rn->tn_sys) return false; if ((ln->tn_sys || rn->tn_sys) && (is_int_constant_zero(ln, lt) || is_int_constant_zero(rn, rt))) return true; if (is_assignment_bool_or_other(op)) return lt != BOOL && (ln->tn_sys || rn->tn_sys); return !is_symmetric_bool_or_other(op); } /* * Some operators require that either both operands are bool or both are * scalar. * * Code that passes this check can be compiled in a pre-C99 environment that * doesn't implement the special rule C99 6.3.1.2, without silent change in * behavior. */ static bool typeok_strict_bool_binary_compatible(op_t op, int arg, const tnode_t *ln, tspec_t lt, const tnode_t *rn, tspec_t rt) { if (is_typeok_strict_bool_binary(op, ln, lt, rn, rt)) return true; if (op == FARG) { /* argument #%d expects '%s', gets passed '%s' */ error(334, arg, tspec_name(lt), tspec_name(rt)); } else if (op == RETURN) { /* function has return type '%s' but returns '%s' */ error(211, tspec_name(lt), tspec_name(rt)); } else { /* operands of '%s' have incompatible types '%s' and '%s' */ error(107, op_name(op), tspec_name(lt), tspec_name(rt)); } return false; } /* * In strict bool mode, check whether the types of the operands match the * operator. */ bool typeok_scalar_strict_bool(op_t op, const mod_t *mp, int arg, const tnode_t *ln, const tnode_t *rn) { tspec_t lt, rt; ln = before_conversion(ln); lt = ln->tn_type->t_tspec; if (rn != NULL) { rn = before_conversion(rn); rt = rn->tn_type->t_tspec; } else { rt = NOTSPEC; } if (rn != NULL && !typeok_strict_bool_binary_compatible(op, arg, ln, lt, rn, rt)) return false; if (mp->m_compares_with_zero) { bool binary = mp->m_binary; bool lbool = is_typeok_bool_compares_with_zero(ln); bool ok = true; if (!binary && !lbool) { /* operand of '%s' must be bool, not '%s' */ error(330, op_name(op), tspec_name(lt)); ok = false; } if (binary && !lbool) { /* left operand of '%s' must be bool, not '%s' */ error(331, op_name(op), tspec_name(lt)); ok = false; } if (binary && op != QUEST && !is_typeok_bool_compares_with_zero(rn)) { /* right operand of '%s' must be bool, not '%s' */ error(332, op_name(op), tspec_name(rt)); ok = false; } return ok; } if (!mp->m_takes_bool) { bool binary = mp->m_binary; bool lbool = lt == BOOL; bool ok = true; if (!binary && lbool) { /* operand of '%s' must not be bool */ error(335, op_name(op)); ok = false; } if (binary && lbool) { /* left operand of '%s' must not be bool */ error(336, op_name(op)); ok = false; } if (binary && rt == BOOL) { /* right operand of '%s' must not be bool */ error(337, op_name(op)); ok = false; } return ok; } return true; } /* * See if the node is valid as operand of an operator that compares its * argument with 0. */ bool is_typeok_bool_compares_with_zero(const tnode_t *tn) { tspec_t t; lint_assert(Tflag); while (tn->tn_op == COMMA) tn = tn->tn_right; tn = before_conversion(tn); t = tn->tn_type->t_tspec; if (t == BOOL) return true; if (tn->tn_sys && is_scalar(t)) return true; /* For enums that are used as bit sets, allow "flags & FLAG". */ if (tn->tn_op == BITAND && tn->tn_left->tn_op == CVT && tn->tn_left->tn_type->t_is_enum && tn->tn_right->tn_type->t_is_enum) return true; return false; } bool fallback_symbol_strict_bool(sym_t *sym) { if (Tflag && strcmp(sym->s_name, "__lint_false") == 0) { sym->s_scl = BOOL_CONST; sym->s_type = gettyp(BOOL); sym->u.s_bool_constant = false; return true; } if (Tflag && strcmp(sym->s_name, "__lint_true") == 0) { sym->s_scl = BOOL_CONST; sym->s_type = gettyp(BOOL); sym->u.s_bool_constant = true; return true; } return false; }