mirror of
https://github.com/pmret/gcc-papermario.git
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1673 lines
48 KiB
C
1673 lines
48 KiB
C
/* Language-level data type conversion for GNU C++.
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Copyright (C) 1987, 88, 92, 93, 94, 95, 1996 Free Software Foundation, Inc.
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Hacked by Michael Tiemann (tiemann@cygnus.com)
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This file is part of GNU CC.
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||
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GNU CC is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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||
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||
GNU CC is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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||
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You should have received a copy of the GNU General Public License
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along with GNU CC; see the file COPYING. If not, write to
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the Free Software Foundation, 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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/* This file contains the functions for converting C expressions
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to different data types. The only entry point is `convert'.
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Every language front end must have a `convert' function
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but what kind of conversions it does will depend on the language. */
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#include "config.h"
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#include <stdio.h>
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#include "tree.h"
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#include "flags.h"
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#include "cp-tree.h"
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#include "class.h"
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#include "convert.h"
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#ifdef HAVE_STDLIB_H
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#include <stdlib.h>
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#endif
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extern tree static_aggregates;
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static tree build_thunk PROTO((tree, tree));
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static tree convert_fn_ptr PROTO((tree, tree));
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static tree cp_convert_to_pointer PROTO((tree, tree));
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static tree convert_to_pointer_force PROTO((tree, tree));
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static tree build_up_reference PROTO((tree, tree, int, int));
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static tree build_type_conversion_1 PROTO((tree, tree, tree, tree,
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int));
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/* Change of width--truncation and extension of integers or reals--
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is represented with NOP_EXPR. Proper functioning of many things
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assumes that no other conversions can be NOP_EXPRs.
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Conversion between integer and pointer is represented with CONVERT_EXPR.
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Converting integer to real uses FLOAT_EXPR
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and real to integer uses FIX_TRUNC_EXPR.
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Here is a list of all the functions that assume that widening and
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narrowing is always done with a NOP_EXPR:
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In convert.c, convert_to_integer.
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In c-typeck.c, build_binary_op_nodefault (boolean ops),
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and truthvalue_conversion.
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In expr.c: expand_expr, for operands of a MULT_EXPR.
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In fold-const.c: fold.
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In tree.c: get_narrower and get_unwidened.
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C++: in multiple-inheritance, converting between pointers may involve
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adjusting them by a delta stored within the class definition. */
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/* Subroutines of `convert'. */
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/* Build a thunk. What it is, is an entry point that when called will
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adjust the this pointer (the first argument) by offset, and then
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goto the real address of the function given by REAL_ADDR that we
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would like called. What we return is the address of the thunk. */
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static tree
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build_thunk (offset, real_addr)
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tree offset, real_addr;
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{
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if (TREE_CODE (real_addr) != ADDR_EXPR
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|| TREE_CODE (TREE_OPERAND (real_addr, 0)) != FUNCTION_DECL)
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{
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sorry ("MI pointer to member conversion too complex");
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return error_mark_node;
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}
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sorry ("MI pointer to member conversion too complex");
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return error_mark_node;
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}
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/* Convert a `pointer to member' (POINTER_TYPE to METHOD_TYPE) into
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another `pointer to method'. This may involved the creation of
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a thunk to handle the this offset calculation. */
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static tree
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convert_fn_ptr (type, expr)
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tree type, expr;
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{
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#if 0 /* We don't use thunks for pmfs. */
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if (flag_vtable_thunks)
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{
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tree intype = TREE_TYPE (expr);
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tree binfo = get_binfo (TYPE_METHOD_BASETYPE (TREE_TYPE (intype)),
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TYPE_METHOD_BASETYPE (TREE_TYPE (type)), 1);
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if (binfo == error_mark_node)
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{
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error (" in pointer to member conversion");
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return error_mark_node;
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}
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if (binfo == NULL_TREE)
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{
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/* ARM 4.8 restriction. */
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error ("invalid pointer to member conversion");
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return error_mark_node;
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}
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if (BINFO_OFFSET_ZEROP (binfo))
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return build1 (NOP_EXPR, type, expr);
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return build1 (NOP_EXPR, type, build_thunk (BINFO_OFFSET (binfo), expr));
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}
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else
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#endif
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return build_ptrmemfunc (type, expr, 1);
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}
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/* if converting pointer to pointer
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if dealing with classes, check for derived->base or vice versa
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else if dealing with method pointers, delegate
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else convert blindly
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else if converting class, pass off to build_type_conversion
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else try C-style pointer conversion */
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static tree
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cp_convert_to_pointer (type, expr)
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tree type, expr;
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{
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register tree intype = TREE_TYPE (expr);
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register enum tree_code form;
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if (IS_AGGR_TYPE (intype))
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{
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tree rval;
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intype = complete_type (intype);
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if (TYPE_SIZE (intype) == NULL_TREE)
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{
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cp_error ("can't convert from incomplete type `%T' to `%T'",
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intype, type);
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return error_mark_node;
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}
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rval = build_type_conversion (CONVERT_EXPR, type, expr, 1);
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if (rval)
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{
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if (rval == error_mark_node)
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cp_error ("conversion of `%E' from `%T' to `%T' is ambiguous",
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expr, intype, type);
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return rval;
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}
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}
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if (TYPE_PTRMEMFUNC_P (type))
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type = TYPE_PTRMEMFUNC_FN_TYPE (type);
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/* Handle anachronistic conversions from (::*)() to cv void* or (*)(). */
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if (TREE_CODE (type) == POINTER_TYPE
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&& (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
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|| TYPE_MAIN_VARIANT (TREE_TYPE (type)) == void_type_node))
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{
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/* Allow an implicit this pointer for pointer to member
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functions. */
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if (TYPE_PTRMEMFUNC_P (intype))
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{
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tree decl, basebinfo;
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tree fntype = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (intype));
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tree t = TYPE_METHOD_BASETYPE (fntype);
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if (current_class_type == 0
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|| get_base_distance (t, current_class_type, 0, &basebinfo)
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== -1)
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{
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decl = build1 (NOP_EXPR, t, error_mark_node);
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}
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else if (current_class_ptr == 0)
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decl = build1 (NOP_EXPR, t, error_mark_node);
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else
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decl = current_class_ref;
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expr = build (OFFSET_REF, fntype, decl, expr);
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}
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if (TREE_CODE (expr) == OFFSET_REF
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&& TREE_CODE (TREE_TYPE (expr)) == METHOD_TYPE)
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expr = resolve_offset_ref (expr);
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if (TREE_CODE (TREE_TYPE (expr)) == METHOD_TYPE)
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expr = build_addr_func (expr);
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if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
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{
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if (TREE_CODE (TREE_TYPE (TREE_TYPE (expr))) == METHOD_TYPE)
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if (pedantic || warn_pmf2ptr)
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cp_pedwarn ("converting from `%T' to `%T'", TREE_TYPE (expr),
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type);
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return build1 (NOP_EXPR, type, expr);
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}
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intype = TREE_TYPE (expr);
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}
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if (TYPE_PTRMEMFUNC_P (intype))
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intype = TYPE_PTRMEMFUNC_FN_TYPE (intype);
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form = TREE_CODE (intype);
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if (form == POINTER_TYPE || form == REFERENCE_TYPE)
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{
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intype = TYPE_MAIN_VARIANT (intype);
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if (TYPE_MAIN_VARIANT (type) != intype
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&& TREE_CODE (TREE_TYPE (type)) == RECORD_TYPE
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&& IS_AGGR_TYPE (TREE_TYPE (type))
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&& IS_AGGR_TYPE (TREE_TYPE (intype))
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&& TREE_CODE (TREE_TYPE (intype)) == RECORD_TYPE)
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{
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enum tree_code code = PLUS_EXPR;
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tree binfo = get_binfo (TREE_TYPE (type), TREE_TYPE (intype), 1);
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if (binfo == error_mark_node)
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return error_mark_node;
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if (binfo == NULL_TREE)
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{
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binfo = get_binfo (TREE_TYPE (intype), TREE_TYPE (type), 1);
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if (binfo == error_mark_node)
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return error_mark_node;
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code = MINUS_EXPR;
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}
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if (binfo)
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{
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if (TYPE_USES_VIRTUAL_BASECLASSES (TREE_TYPE (type))
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|| TYPE_USES_VIRTUAL_BASECLASSES (TREE_TYPE (intype))
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|| ! BINFO_OFFSET_ZEROP (binfo))
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{
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/* Need to get the path we took. */
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tree path;
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if (code == PLUS_EXPR)
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get_base_distance (TREE_TYPE (type), TREE_TYPE (intype), 0, &path);
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else
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get_base_distance (TREE_TYPE (intype), TREE_TYPE (type), 0, &path);
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return build_vbase_path (code, type, expr, path, 0);
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}
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}
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}
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if (TREE_CODE (TREE_TYPE (intype)) == METHOD_TYPE
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&& TREE_CODE (type) == POINTER_TYPE
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&& TREE_CODE (TREE_TYPE (type)) == METHOD_TYPE)
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return convert_fn_ptr (type, expr);
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if (TREE_CODE (TREE_TYPE (type)) == OFFSET_TYPE
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&& TREE_CODE (TREE_TYPE (intype)) == OFFSET_TYPE)
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{
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tree b1 = TYPE_OFFSET_BASETYPE (TREE_TYPE (type));
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tree b2 = TYPE_OFFSET_BASETYPE (TREE_TYPE (intype));
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tree binfo = get_binfo (b1, b2, 1);
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if (binfo == NULL_TREE)
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binfo = get_binfo (b2, b1, 1);
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if (binfo == error_mark_node)
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return error_mark_node;
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}
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if (TREE_CODE (TREE_TYPE (intype)) == METHOD_TYPE
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|| (TREE_CODE (type) == POINTER_TYPE
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&& TREE_CODE (TREE_TYPE (type)) == METHOD_TYPE))
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{
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cp_error ("cannot convert `%E' from type `%T' to type `%T'",
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expr, intype, type);
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return error_mark_node;
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}
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return build1 (NOP_EXPR, type, expr);
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}
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my_friendly_assert (form != OFFSET_TYPE, 186);
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if (TYPE_LANG_SPECIFIC (intype)
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&& (IS_SIGNATURE_POINTER (intype) || IS_SIGNATURE_REFERENCE (intype)))
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return convert_to_pointer (type, build_optr_ref (expr));
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if (integer_zerop (expr))
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{
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if (TREE_CODE (TREE_TYPE (type)) == METHOD_TYPE)
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return build_ptrmemfunc (type, expr, 0);
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expr = build_int_2 (0, 0);
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TREE_TYPE (expr) = type;
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return expr;
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}
|
||
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if (INTEGRAL_CODE_P (form))
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{
|
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if (type_precision (intype) == POINTER_SIZE)
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return build1 (CONVERT_EXPR, type, expr);
|
||
expr = cp_convert (type_for_size (POINTER_SIZE, 0), expr);
|
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/* Modes may be different but sizes should be the same. */
|
||
if (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (expr)))
|
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!= GET_MODE_SIZE (TYPE_MODE (type)))
|
||
/* There is supposed to be some integral type
|
||
that is the same width as a pointer. */
|
||
abort ();
|
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return convert_to_pointer (type, expr);
|
||
}
|
||
|
||
cp_error ("cannot convert `%E' from type `%T' to type `%T'",
|
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expr, intype, type);
|
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return error_mark_node;
|
||
}
|
||
|
||
/* Like convert, except permit conversions to take place which
|
||
are not normally allowed due to access restrictions
|
||
(such as conversion from sub-type to private super-type). */
|
||
|
||
static tree
|
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convert_to_pointer_force (type, expr)
|
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tree type, expr;
|
||
{
|
||
register tree intype = TREE_TYPE (expr);
|
||
register enum tree_code form = TREE_CODE (intype);
|
||
|
||
if (integer_zerop (expr))
|
||
{
|
||
expr = build_int_2 (0, 0);
|
||
TREE_TYPE (expr) = type;
|
||
return expr;
|
||
}
|
||
|
||
/* Convert signature pointer/reference to `void *' first. */
|
||
if (form == RECORD_TYPE
|
||
&& (IS_SIGNATURE_POINTER (intype) || IS_SIGNATURE_REFERENCE (intype)))
|
||
{
|
||
expr = build_optr_ref (expr);
|
||
intype = TREE_TYPE (expr);
|
||
form = TREE_CODE (intype);
|
||
}
|
||
|
||
if (form == POINTER_TYPE)
|
||
{
|
||
intype = TYPE_MAIN_VARIANT (intype);
|
||
|
||
if (TYPE_MAIN_VARIANT (type) != intype
|
||
&& TREE_CODE (TREE_TYPE (type)) == RECORD_TYPE
|
||
&& IS_AGGR_TYPE (TREE_TYPE (type))
|
||
&& IS_AGGR_TYPE (TREE_TYPE (intype))
|
||
&& TREE_CODE (TREE_TYPE (intype)) == RECORD_TYPE)
|
||
{
|
||
enum tree_code code = PLUS_EXPR;
|
||
tree path;
|
||
int distance = get_base_distance (TREE_TYPE (type),
|
||
TREE_TYPE (intype), 0, &path);
|
||
if (distance == -2)
|
||
{
|
||
ambig:
|
||
cp_error ("type `%T' is ambiguous baseclass of `%s'",
|
||
TREE_TYPE (type),
|
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TYPE_NAME_STRING (TREE_TYPE (intype)));
|
||
return error_mark_node;
|
||
}
|
||
if (distance == -1)
|
||
{
|
||
distance = get_base_distance (TREE_TYPE (intype),
|
||
TREE_TYPE (type), 0, &path);
|
||
if (distance == -2)
|
||
goto ambig;
|
||
if (distance < 0)
|
||
/* Doesn't need any special help from us. */
|
||
return build1 (NOP_EXPR, type, expr);
|
||
|
||
code = MINUS_EXPR;
|
||
}
|
||
return build_vbase_path (code, type, expr, path, 0);
|
||
}
|
||
}
|
||
|
||
return cp_convert_to_pointer (type, expr);
|
||
}
|
||
|
||
/* We are passing something to a function which requires a reference.
|
||
The type we are interested in is in TYPE. The initial
|
||
value we have to begin with is in ARG.
|
||
|
||
FLAGS controls how we manage access checking.
|
||
DIRECT_BIND in FLAGS controls how any temporaries are generated. */
|
||
|
||
static tree
|
||
build_up_reference (type, arg, flags, checkconst)
|
||
tree type, arg;
|
||
int flags, checkconst;
|
||
{
|
||
tree rval;
|
||
tree argtype = TREE_TYPE (arg);
|
||
tree target_type = TREE_TYPE (type);
|
||
|
||
my_friendly_assert (TREE_CODE (type) == REFERENCE_TYPE, 187);
|
||
|
||
if ((flags & DIRECT_BIND) && ! real_lvalue_p (arg))
|
||
{
|
||
tree targ = arg;
|
||
if (toplevel_bindings_p ())
|
||
arg = get_temp_name (argtype, 1);
|
||
else
|
||
{
|
||
arg = pushdecl (build_decl (VAR_DECL, NULL_TREE, argtype));
|
||
DECL_ARTIFICIAL (arg) = 1;
|
||
}
|
||
DECL_INITIAL (arg) = targ;
|
||
cp_finish_decl (arg, targ, NULL_TREE, 0, LOOKUP_ONLYCONVERTING);
|
||
}
|
||
else if (!(flags & DIRECT_BIND) && ! lvalue_p (arg))
|
||
{
|
||
tree slot = build_decl (VAR_DECL, NULL_TREE, argtype);
|
||
arg = build (TARGET_EXPR, argtype, slot, arg, NULL_TREE, NULL_TREE);
|
||
}
|
||
|
||
/* If we had a way to wrap this up, and say, if we ever needed it's
|
||
address, transform all occurrences of the register, into a memory
|
||
reference we could win better. */
|
||
rval = build_unary_op (ADDR_EXPR, arg, 1);
|
||
if ((flags & LOOKUP_PROTECT)
|
||
&& TYPE_MAIN_VARIANT (argtype) != TYPE_MAIN_VARIANT (target_type)
|
||
&& IS_AGGR_TYPE (argtype)
|
||
&& IS_AGGR_TYPE (target_type))
|
||
{
|
||
/* We go through get_binfo for the access control. */
|
||
tree binfo = get_binfo (target_type, argtype, 1);
|
||
if (binfo == error_mark_node)
|
||
return error_mark_node;
|
||
if (binfo == NULL_TREE)
|
||
return error_not_base_type (target_type, argtype);
|
||
rval = convert_pointer_to_real (binfo, rval);
|
||
}
|
||
else
|
||
rval
|
||
= convert_to_pointer_force (build_pointer_type (target_type), rval);
|
||
rval = build1 (NOP_EXPR, type, rval);
|
||
TREE_CONSTANT (rval) = TREE_CONSTANT (TREE_OPERAND (rval, 0));
|
||
return rval;
|
||
}
|
||
|
||
/* For C++: Only need to do one-level references, but cannot
|
||
get tripped up on signed/unsigned differences.
|
||
|
||
DECL is either NULL_TREE or the _DECL node for a reference that is being
|
||
initialized. It can be error_mark_node if we don't know the _DECL but
|
||
we know it's an initialization. */
|
||
|
||
tree
|
||
convert_to_reference (reftype, expr, convtype, flags, decl)
|
||
tree reftype, expr;
|
||
int convtype, flags;
|
||
tree decl;
|
||
{
|
||
register tree type = TYPE_MAIN_VARIANT (TREE_TYPE (reftype));
|
||
register tree intype = TREE_TYPE (expr);
|
||
tree rval = NULL_TREE;
|
||
tree rval_as_conversion = NULL_TREE;
|
||
int i;
|
||
|
||
if (TREE_CODE (intype) == REFERENCE_TYPE)
|
||
my_friendly_abort (364);
|
||
|
||
intype = TYPE_MAIN_VARIANT (intype);
|
||
|
||
i = comp_target_types (type, intype, 0);
|
||
|
||
if (i <= 0 && (convtype & CONV_IMPLICIT) && IS_AGGR_TYPE (intype)
|
||
&& ! (flags & LOOKUP_NO_CONVERSION))
|
||
{
|
||
/* Look for a user-defined conversion to lvalue that we can use. */
|
||
|
||
if (flag_ansi_overloading)
|
||
rval_as_conversion
|
||
= build_type_conversion (CONVERT_EXPR, reftype, expr, 1);
|
||
else
|
||
rval_as_conversion = build_type_conversion (CONVERT_EXPR, type, expr, 1);
|
||
|
||
if (rval_as_conversion && rval_as_conversion != error_mark_node
|
||
&& real_lvalue_p (rval_as_conversion))
|
||
{
|
||
expr = rval_as_conversion;
|
||
rval_as_conversion = NULL_TREE;
|
||
intype = type;
|
||
i = 1;
|
||
}
|
||
}
|
||
|
||
if (((convtype & CONV_STATIC) && i == -1)
|
||
|| ((convtype & CONV_IMPLICIT) && i == 1))
|
||
{
|
||
if (flags & LOOKUP_COMPLAIN)
|
||
{
|
||
tree ttl = TREE_TYPE (reftype);
|
||
tree ttr;
|
||
|
||
{
|
||
int r = TREE_READONLY (expr);
|
||
int v = TREE_THIS_VOLATILE (expr);
|
||
ttr = cp_build_type_variant (TREE_TYPE (expr), r, v);
|
||
}
|
||
|
||
if (! real_lvalue_p (expr) && ! TYPE_READONLY (ttl))
|
||
{
|
||
if (decl)
|
||
/* Ensure semantics of [dcl.init.ref] */
|
||
cp_pedwarn ("initialization of non-const reference `%#T' from rvalue `%T'",
|
||
reftype, intype);
|
||
else
|
||
cp_pedwarn ("conversion to non-const `%T' from rvalue `%T'",
|
||
reftype, intype);
|
||
}
|
||
else if (! (convtype & CONV_CONST))
|
||
{
|
||
if (! TYPE_READONLY (ttl) && TYPE_READONLY (ttr))
|
||
cp_pedwarn ("conversion from `%T' to `%T' discards const",
|
||
ttr, reftype);
|
||
else if (! TYPE_VOLATILE (ttl) && TYPE_VOLATILE (ttr))
|
||
cp_pedwarn ("conversion from `%T' to `%T' discards volatile",
|
||
ttr, reftype);
|
||
}
|
||
}
|
||
|
||
return build_up_reference (reftype, expr, flags,
|
||
! (convtype & CONV_CONST));
|
||
}
|
||
else if ((convtype & CONV_REINTERPRET) && lvalue_p (expr))
|
||
{
|
||
/* When casting an lvalue to a reference type, just convert into
|
||
a pointer to the new type and deference it. This is allowed
|
||
by San Diego WP section 5.2.9 paragraph 12, though perhaps it
|
||
should be done directly (jason). (int &)ri ---> *(int*)&ri */
|
||
|
||
/* B* bp; A& ar = (A&)bp; is valid, but it's probably not what they
|
||
meant. */
|
||
if (TREE_CODE (intype) == POINTER_TYPE
|
||
&& (comptypes (TREE_TYPE (intype), type, -1)))
|
||
cp_warning ("casting `%T' to `%T' does not dereference pointer",
|
||
intype, reftype);
|
||
|
||
rval = build_unary_op (ADDR_EXPR, expr, 0);
|
||
if (rval != error_mark_node)
|
||
rval = convert_force (build_pointer_type (TREE_TYPE (reftype)), rval, 0);
|
||
if (rval != error_mark_node)
|
||
rval = build1 (NOP_EXPR, reftype, rval);
|
||
}
|
||
else if (flag_ansi_overloading)
|
||
{
|
||
rval = convert_for_initialization (NULL_TREE, type, expr, flags,
|
||
"converting", 0, 0);
|
||
if (rval == error_mark_node)
|
||
return error_mark_node;
|
||
rval = build_up_reference (reftype, rval, flags, 1);
|
||
|
||
if (rval && ! TYPE_READONLY (TREE_TYPE (reftype)))
|
||
cp_pedwarn ("initializing non-const `%T' with `%T' will use a temporary",
|
||
reftype, intype);
|
||
}
|
||
else
|
||
{
|
||
tree rval_as_ctor = NULL_TREE;
|
||
|
||
if (rval_as_conversion)
|
||
{
|
||
if (rval_as_conversion == error_mark_node)
|
||
{
|
||
cp_error ("conversion from `%T' to `%T' is ambiguous",
|
||
intype, reftype);
|
||
return error_mark_node;
|
||
}
|
||
rval_as_conversion = build_up_reference (reftype, rval_as_conversion,
|
||
flags, 1);
|
||
}
|
||
|
||
/* Definitely need to go through a constructor here. */
|
||
if (TYPE_HAS_CONSTRUCTOR (type)
|
||
&& ! CLASSTYPE_ABSTRACT_VIRTUALS (type)
|
||
&& (rval = build_method_call
|
||
(NULL_TREE, ctor_identifier,
|
||
build_expr_list (NULL_TREE, expr), TYPE_BINFO (type),
|
||
LOOKUP_NO_CONVERSION|LOOKUP_SPECULATIVELY
|
||
| LOOKUP_ONLYCONVERTING)))
|
||
{
|
||
tree init;
|
||
|
||
if (toplevel_bindings_p ())
|
||
{
|
||
tree t = get_temp_name (type, toplevel_bindings_p ());
|
||
init = build_method_call (t, ctor_identifier,
|
||
build_expr_list (NULL_TREE, expr),
|
||
TYPE_BINFO (type),
|
||
LOOKUP_NORMAL|LOOKUP_NO_CONVERSION
|
||
| LOOKUP_ONLYCONVERTING);
|
||
|
||
if (init == error_mark_node)
|
||
return error_mark_node;
|
||
|
||
make_decl_rtl (t, NULL_PTR, 1);
|
||
static_aggregates = perm_tree_cons (expr, t, static_aggregates);
|
||
rval = build_unary_op (ADDR_EXPR, t, 0);
|
||
}
|
||
else
|
||
{
|
||
init = build_method_call (NULL_TREE, ctor_identifier,
|
||
build_expr_list (NULL_TREE, expr),
|
||
TYPE_BINFO (type),
|
||
LOOKUP_NORMAL|LOOKUP_NO_CONVERSION
|
||
|LOOKUP_ONLYCONVERTING);
|
||
|
||
if (init == error_mark_node)
|
||
return error_mark_node;
|
||
|
||
rval = build_cplus_new (type, init);
|
||
rval = build_up_reference (reftype, rval, flags, 1);
|
||
}
|
||
rval_as_ctor = rval;
|
||
}
|
||
|
||
if (rval_as_ctor && rval_as_conversion)
|
||
{
|
||
cp_error ("ambiguous conversion from `%T' to `%T'; both user-defined conversion and constructor apply",
|
||
intype, reftype);
|
||
return error_mark_node;
|
||
}
|
||
else if (rval_as_ctor)
|
||
rval = rval_as_ctor;
|
||
else if (rval_as_conversion)
|
||
rval = rval_as_conversion;
|
||
else if (! IS_AGGR_TYPE (type) && ! IS_AGGR_TYPE (intype))
|
||
{
|
||
rval = cp_convert (type, expr);
|
||
if (rval == error_mark_node)
|
||
return error_mark_node;
|
||
|
||
rval = build_up_reference (reftype, rval, flags, 1);
|
||
}
|
||
|
||
if (rval && ! TYPE_READONLY (TREE_TYPE (reftype)))
|
||
cp_pedwarn ("initializing non-const `%T' with `%T' will use a temporary",
|
||
reftype, intype);
|
||
}
|
||
|
||
if (rval)
|
||
{
|
||
/* If we found a way to convert earlier, then use it. */
|
||
return rval;
|
||
}
|
||
|
||
my_friendly_assert (TREE_CODE (intype) != OFFSET_TYPE, 189);
|
||
|
||
if (flags & LOOKUP_COMPLAIN)
|
||
cp_error ("cannot convert type `%T' to type `%T'", intype, reftype);
|
||
|
||
if (flags & LOOKUP_SPECULATIVELY)
|
||
return NULL_TREE;
|
||
|
||
return error_mark_node;
|
||
}
|
||
|
||
/* We are using a reference VAL for its value. Bash that reference all the
|
||
way down to its lowest form. */
|
||
|
||
tree
|
||
convert_from_reference (val)
|
||
tree val;
|
||
{
|
||
tree type = TREE_TYPE (val);
|
||
|
||
if (TREE_CODE (type) == OFFSET_TYPE)
|
||
type = TREE_TYPE (type);
|
||
if (TREE_CODE (type) == REFERENCE_TYPE)
|
||
return build_indirect_ref (val, NULL_PTR);
|
||
return val;
|
||
}
|
||
|
||
/* See if there is a constructor of type TYPE which will convert
|
||
EXPR. The reference manual seems to suggest (8.5.6) that we need
|
||
not worry about finding constructors for base classes, then converting
|
||
to the derived class.
|
||
|
||
MSGP is a pointer to a message that would be an appropriate error
|
||
string. If MSGP is NULL, then we are not interested in reporting
|
||
errors. */
|
||
|
||
tree
|
||
convert_to_aggr (type, expr, msgp, protect)
|
||
tree type, expr;
|
||
char **msgp;
|
||
int protect;
|
||
{
|
||
tree basetype = type;
|
||
tree name = TYPE_IDENTIFIER (basetype);
|
||
tree function, fndecl, fntype, parmtypes, parmlist, result;
|
||
#if 0
|
||
/* See code below that used this. */
|
||
tree method_name;
|
||
#endif
|
||
tree access;
|
||
int can_be_private, can_be_protected;
|
||
|
||
if (! TYPE_HAS_CONSTRUCTOR (basetype))
|
||
{
|
||
if (msgp)
|
||
*msgp = "type `%s' does not have a constructor";
|
||
return error_mark_node;
|
||
}
|
||
|
||
access = access_public_node;
|
||
can_be_private = 0;
|
||
can_be_protected = IDENTIFIER_CLASS_VALUE (name) || name == current_class_name;
|
||
|
||
parmlist = build_expr_list (NULL_TREE, expr);
|
||
parmtypes = scratch_tree_cons (NULL_TREE, TREE_TYPE (expr), void_list_node);
|
||
|
||
if (TYPE_USES_VIRTUAL_BASECLASSES (basetype))
|
||
{
|
||
parmtypes = expr_tree_cons (NULL_TREE, integer_type_node, parmtypes);
|
||
parmlist = scratch_tree_cons (NULL_TREE, integer_one_node, parmlist);
|
||
}
|
||
|
||
/* The type of the first argument will be filled in inside the loop. */
|
||
parmlist = expr_tree_cons (NULL_TREE, integer_zero_node, parmlist);
|
||
parmtypes = scratch_tree_cons (NULL_TREE, build_pointer_type (basetype), parmtypes);
|
||
|
||
/* No exact conversion was found. See if an approximate
|
||
one will do. */
|
||
fndecl = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (basetype), 0);
|
||
|
||
{
|
||
int saw_private = 0;
|
||
int saw_protected = 0;
|
||
struct candidate *candidates
|
||
= (struct candidate *) alloca ((decl_list_length (fndecl)+1) * sizeof (struct candidate));
|
||
struct candidate *cp = candidates;
|
||
|
||
while (fndecl)
|
||
{
|
||
function = fndecl;
|
||
cp->h_len = 2;
|
||
cp->harshness = (struct harshness_code *)
|
||
alloca (3 * sizeof (struct harshness_code));
|
||
|
||
compute_conversion_costs (fndecl, parmlist, cp, 2);
|
||
if ((cp->h.code & EVIL_CODE) == 0)
|
||
{
|
||
cp->u.field = fndecl;
|
||
if (protect)
|
||
{
|
||
if (TREE_PRIVATE (fndecl))
|
||
access = access_private_node;
|
||
else if (TREE_PROTECTED (fndecl))
|
||
access = access_protected_node;
|
||
else
|
||
access = access_public_node;
|
||
}
|
||
else
|
||
access = access_public_node;
|
||
|
||
if (access == access_private_node
|
||
? (basetype == current_class_type
|
||
|| is_friend (basetype, cp->function)
|
||
|| purpose_member (basetype, DECL_ACCESS (fndecl)))
|
||
: access == access_protected_node
|
||
? (can_be_protected
|
||
|| purpose_member (basetype, DECL_ACCESS (fndecl)))
|
||
: 1)
|
||
{
|
||
if (cp->h.code <= TRIVIAL_CODE)
|
||
goto found_and_ok;
|
||
cp++;
|
||
}
|
||
else
|
||
{
|
||
if (access == access_private_node)
|
||
saw_private = 1;
|
||
else
|
||
saw_protected = 1;
|
||
}
|
||
}
|
||
fndecl = DECL_CHAIN (fndecl);
|
||
}
|
||
if (cp - candidates)
|
||
{
|
||
/* Rank from worst to best. Then cp will point to best one.
|
||
Private fields have their bits flipped. For unsigned
|
||
numbers, this should make them look very large.
|
||
If the best alternate has a (signed) negative value,
|
||
then all we ever saw were private members. */
|
||
if (cp - candidates > 1)
|
||
qsort (candidates, /* char *base */
|
||
cp - candidates, /* int nel */
|
||
sizeof (struct candidate), /* int width */
|
||
(int (*) PROTO((const void *, const void *))) rank_for_overload); /* int (*compar)() */
|
||
|
||
--cp;
|
||
if (cp->h.code & EVIL_CODE)
|
||
{
|
||
if (msgp)
|
||
*msgp = "ambiguous type conversion possible for `%s'";
|
||
return error_mark_node;
|
||
}
|
||
|
||
function = cp->function;
|
||
fndecl = cp->u.field;
|
||
goto found_and_ok;
|
||
}
|
||
else if (msgp)
|
||
{
|
||
if (saw_private)
|
||
if (saw_protected)
|
||
*msgp = "only private and protected conversions apply";
|
||
else
|
||
*msgp = "only private conversions apply";
|
||
else if (saw_protected)
|
||
*msgp = "only protected conversions apply";
|
||
else
|
||
*msgp = "no appropriate conversion to type `%s'";
|
||
}
|
||
return error_mark_node;
|
||
}
|
||
/* NOTREACHED */
|
||
|
||
found:
|
||
if (access == access_private_node)
|
||
if (! can_be_private)
|
||
{
|
||
if (msgp)
|
||
*msgp = TREE_PRIVATE (fndecl)
|
||
? "conversion to type `%s' is private"
|
||
: "conversion to type `%s' is from private base class";
|
||
return error_mark_node;
|
||
}
|
||
if (access == access_protected_node)
|
||
if (! can_be_protected)
|
||
{
|
||
if (msgp)
|
||
*msgp = TREE_PRIVATE (fndecl)
|
||
? "conversion to type `%s' is protected"
|
||
: "conversion to type `%s' is from protected base class";
|
||
return error_mark_node;
|
||
}
|
||
function = fndecl;
|
||
found_and_ok:
|
||
|
||
/* It will convert, but we don't do anything about it yet. */
|
||
if (msgp == 0)
|
||
return NULL_TREE;
|
||
|
||
fntype = TREE_TYPE (function);
|
||
|
||
parmlist = convert_arguments (NULL_TREE, TYPE_ARG_TYPES (fntype),
|
||
parmlist, NULL_TREE, LOOKUP_NORMAL);
|
||
|
||
result = build_call (function, TREE_TYPE (fntype), parmlist);
|
||
return result;
|
||
}
|
||
|
||
/* Call this when we know (for any reason) that expr is not, in fact,
|
||
zero. This routine is like convert_pointer_to, but it pays
|
||
attention to which specific instance of what type we want to
|
||
convert to. This routine should eventually become
|
||
convert_to_pointer after all references to convert_to_pointer
|
||
are removed. */
|
||
|
||
tree
|
||
convert_pointer_to_real (binfo, expr)
|
||
tree binfo, expr;
|
||
{
|
||
register tree intype = TREE_TYPE (expr);
|
||
tree ptr_type;
|
||
tree type, rval;
|
||
|
||
if (TREE_CODE (binfo) == TREE_VEC)
|
||
type = BINFO_TYPE (binfo);
|
||
else if (IS_AGGR_TYPE (binfo))
|
||
{
|
||
type = binfo;
|
||
}
|
||
else
|
||
{
|
||
type = binfo;
|
||
binfo = NULL_TREE;
|
||
}
|
||
|
||
ptr_type = cp_build_type_variant (type, TYPE_READONLY (TREE_TYPE (intype)),
|
||
TYPE_VOLATILE (TREE_TYPE (intype)));
|
||
ptr_type = build_pointer_type (ptr_type);
|
||
if (ptr_type == TYPE_MAIN_VARIANT (intype))
|
||
return expr;
|
||
|
||
if (intype == error_mark_node)
|
||
return error_mark_node;
|
||
|
||
my_friendly_assert (!integer_zerop (expr), 191);
|
||
|
||
if (TREE_CODE (type) == RECORD_TYPE
|
||
&& TREE_CODE (TREE_TYPE (intype)) == RECORD_TYPE
|
||
&& type != TYPE_MAIN_VARIANT (TREE_TYPE (intype)))
|
||
{
|
||
tree path;
|
||
int distance
|
||
= get_base_distance (binfo, TYPE_MAIN_VARIANT (TREE_TYPE (intype)),
|
||
0, &path);
|
||
|
||
/* This function shouldn't be called with unqualified arguments
|
||
but if it is, give them an error message that they can read. */
|
||
if (distance < 0)
|
||
{
|
||
cp_error ("cannot convert a pointer of type `%T' to a pointer of type `%T'",
|
||
TREE_TYPE (intype), type);
|
||
|
||
if (distance == -2)
|
||
cp_error ("because `%T' is an ambiguous base class", type);
|
||
return error_mark_node;
|
||
}
|
||
|
||
return build_vbase_path (PLUS_EXPR, ptr_type, expr, path, 1);
|
||
}
|
||
rval = build1 (NOP_EXPR, ptr_type,
|
||
TREE_CODE (expr) == NOP_EXPR ? TREE_OPERAND (expr, 0) : expr);
|
||
TREE_CONSTANT (rval) = TREE_CONSTANT (expr);
|
||
return rval;
|
||
}
|
||
|
||
/* Call this when we know (for any reason) that expr is
|
||
not, in fact, zero. This routine gets a type out of the first
|
||
argument and uses it to search for the type to convert to. If there
|
||
is more than one instance of that type in the expr, the conversion is
|
||
ambiguous. This routine should eventually go away, and all
|
||
callers should use convert_to_pointer_real. */
|
||
|
||
tree
|
||
convert_pointer_to (binfo, expr)
|
||
tree binfo, expr;
|
||
{
|
||
tree type;
|
||
|
||
if (TREE_CODE (binfo) == TREE_VEC)
|
||
type = BINFO_TYPE (binfo);
|
||
else if (IS_AGGR_TYPE (binfo))
|
||
type = binfo;
|
||
else
|
||
type = binfo;
|
||
return convert_pointer_to_real (type, expr);
|
||
}
|
||
|
||
/* C++ conversions, preference to static cast conversions. */
|
||
|
||
tree
|
||
cp_convert (type, expr)
|
||
tree type, expr;
|
||
{
|
||
return ocp_convert (type, expr, CONV_OLD_CONVERT, LOOKUP_NORMAL);
|
||
}
|
||
|
||
/* Conversion...
|
||
|
||
FLAGS indicates how we should behave. */
|
||
|
||
tree
|
||
ocp_convert (type, expr, convtype, flags)
|
||
tree type, expr;
|
||
int convtype, flags;
|
||
{
|
||
register tree e = expr;
|
||
register enum tree_code code = TREE_CODE (type);
|
||
|
||
if (e == error_mark_node
|
||
|| TREE_TYPE (e) == error_mark_node)
|
||
return error_mark_node;
|
||
|
||
if (IS_AGGR_TYPE (type) && (convtype & CONV_FORCE_TEMP))
|
||
/* We need a new temporary; don't take this shortcut. */;
|
||
else if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (TREE_TYPE (e)))
|
||
/* Trivial conversion: cv-qualifiers do not matter on rvalues. */
|
||
return fold (build1 (NOP_EXPR, type, e));
|
||
|
||
if (code == VOID_TYPE && (convtype & CONV_STATIC))
|
||
return build1 (CONVERT_EXPR, type, e);
|
||
|
||
#if 0
|
||
/* This is incorrect. A truncation can't be stripped this way.
|
||
Extensions will be stripped by the use of get_unwidened. */
|
||
if (TREE_CODE (e) == NOP_EXPR)
|
||
return cp_convert (type, TREE_OPERAND (e, 0));
|
||
#endif
|
||
|
||
/* Just convert to the type of the member. */
|
||
if (code == OFFSET_TYPE)
|
||
{
|
||
type = TREE_TYPE (type);
|
||
code = TREE_CODE (type);
|
||
}
|
||
|
||
#if 0
|
||
if (code == REFERENCE_TYPE)
|
||
return fold (convert_to_reference (type, e, convtype, flags, NULL_TREE));
|
||
else if (TREE_CODE (TREE_TYPE (e)) == REFERENCE_TYPE)
|
||
e = convert_from_reference (e);
|
||
#endif
|
||
|
||
if (TREE_CODE (e) == OFFSET_REF)
|
||
e = resolve_offset_ref (e);
|
||
|
||
if (TREE_READONLY_DECL_P (e))
|
||
e = decl_constant_value (e);
|
||
|
||
if (INTEGRAL_CODE_P (code))
|
||
{
|
||
tree intype = TREE_TYPE (e);
|
||
/* enum = enum, enum = int, enum = float, (enum)pointer are all
|
||
errors. */
|
||
if (flag_int_enum_equivalence == 0
|
||
&& TREE_CODE (type) == ENUMERAL_TYPE
|
||
&& ((ARITHMETIC_TYPE_P (intype) && ! (convtype & CONV_STATIC))
|
||
|| (TREE_CODE (intype) == POINTER_TYPE)))
|
||
{
|
||
cp_pedwarn ("conversion from `%#T' to `%#T'", intype, type);
|
||
|
||
if (flag_pedantic_errors)
|
||
return error_mark_node;
|
||
}
|
||
if (IS_AGGR_TYPE (intype))
|
||
{
|
||
tree rval;
|
||
rval = build_type_conversion (CONVERT_EXPR, type, e, 1);
|
||
if (rval)
|
||
return rval;
|
||
if (flags & LOOKUP_COMPLAIN)
|
||
cp_error ("`%#T' used where a `%T' was expected", intype, type);
|
||
if (flags & LOOKUP_SPECULATIVELY)
|
||
return NULL_TREE;
|
||
return error_mark_node;
|
||
}
|
||
if (code == BOOLEAN_TYPE)
|
||
{
|
||
/* Common Ada/Pascal programmer's mistake. We always warn
|
||
about this since it is so bad. */
|
||
if (TREE_CODE (expr) == FUNCTION_DECL)
|
||
cp_warning ("the address of `%D', will always be `true'", expr);
|
||
return truthvalue_conversion (e);
|
||
}
|
||
return fold (convert_to_integer (type, e));
|
||
}
|
||
if (code == POINTER_TYPE || code == REFERENCE_TYPE
|
||
|| TYPE_PTRMEMFUNC_P (type))
|
||
return fold (cp_convert_to_pointer (type, e));
|
||
if (code == REAL_TYPE || code == COMPLEX_TYPE)
|
||
{
|
||
if (IS_AGGR_TYPE (TREE_TYPE (e)))
|
||
{
|
||
tree rval;
|
||
rval = build_type_conversion (CONVERT_EXPR, type, e, 1);
|
||
if (rval)
|
||
return rval;
|
||
else
|
||
if (flags & LOOKUP_COMPLAIN)
|
||
cp_error ("`%#T' used where a floating point value was expected",
|
||
TREE_TYPE (e));
|
||
}
|
||
if (code == REAL_TYPE)
|
||
return fold (convert_to_real (type, e));
|
||
else if (code == COMPLEX_TYPE)
|
||
return fold (convert_to_complex (type, e));
|
||
}
|
||
|
||
/* New C++ semantics: since assignment is now based on
|
||
memberwise copying, if the rhs type is derived from the
|
||
lhs type, then we may still do a conversion. */
|
||
if (IS_AGGR_TYPE_CODE (code))
|
||
{
|
||
tree dtype = TREE_TYPE (e);
|
||
tree ctor = NULL_TREE;
|
||
tree conversion = NULL_TREE;
|
||
|
||
dtype = TYPE_MAIN_VARIANT (dtype);
|
||
|
||
/* Conversion of object pointers or signature pointers/references
|
||
to signature pointers/references. */
|
||
|
||
if (TYPE_LANG_SPECIFIC (type)
|
||
&& (IS_SIGNATURE_POINTER (type) || IS_SIGNATURE_REFERENCE (type)))
|
||
{
|
||
tree constructor = build_signature_pointer_constructor (type, expr);
|
||
tree sig_ty = SIGNATURE_TYPE (type);
|
||
tree sig_ptr;
|
||
|
||
if (constructor == error_mark_node)
|
||
return error_mark_node;
|
||
|
||
sig_ptr = get_temp_name (type, 1);
|
||
DECL_INITIAL (sig_ptr) = constructor;
|
||
CLEAR_SIGNATURE (sig_ty);
|
||
cp_finish_decl (sig_ptr, constructor, NULL_TREE, 0, 0);
|
||
SET_SIGNATURE (sig_ty);
|
||
TREE_READONLY (sig_ptr) = 1;
|
||
|
||
return sig_ptr;
|
||
}
|
||
|
||
/* Conversion between aggregate types. New C++ semantics allow
|
||
objects of derived type to be cast to objects of base type.
|
||
Old semantics only allowed this between pointers.
|
||
|
||
There may be some ambiguity between using a constructor
|
||
vs. using a type conversion operator when both apply. */
|
||
|
||
if (flag_ansi_overloading)
|
||
{
|
||
ctor = e;
|
||
|
||
if ((flags & LOOKUP_ONLYCONVERTING)
|
||
&& ! (IS_AGGR_TYPE (dtype) && DERIVED_FROM_P (type, dtype)))
|
||
{
|
||
ctor = build_user_type_conversion (type, ctor, flags);
|
||
flags |= LOOKUP_NO_CONVERSION;
|
||
}
|
||
if (ctor)
|
||
ctor = build_method_call (NULL_TREE, ctor_identifier,
|
||
build_expr_list (NULL_TREE, ctor),
|
||
TYPE_BINFO (type), flags);
|
||
if (ctor)
|
||
return build_cplus_new (type, ctor);
|
||
}
|
||
else
|
||
{
|
||
if (IS_AGGR_TYPE (dtype) && ! DERIVED_FROM_P (type, dtype)
|
||
&& TYPE_HAS_CONVERSION (dtype))
|
||
conversion = build_type_conversion (CONVERT_EXPR, type, e, 1);
|
||
|
||
if (conversion == error_mark_node)
|
||
{
|
||
if (flags & LOOKUP_COMPLAIN)
|
||
error ("ambiguous pointer conversion");
|
||
return conversion;
|
||
}
|
||
|
||
if (TYPE_HAS_CONSTRUCTOR (complete_type (type)))
|
||
ctor = build_method_call (NULL_TREE, ctor_identifier,
|
||
build_expr_list (NULL_TREE, e),
|
||
TYPE_BINFO (type),
|
||
(flags & LOOKUP_NORMAL)
|
||
| LOOKUP_SPECULATIVELY
|
||
| (flags & LOOKUP_ONLYCONVERTING)
|
||
| (flags & LOOKUP_NO_CONVERSION)
|
||
| (conversion ? LOOKUP_NO_CONVERSION : 0));
|
||
|
||
if (ctor == error_mark_node)
|
||
{
|
||
if (flags & LOOKUP_COMPLAIN)
|
||
cp_error ("in conversion to type `%T'", type);
|
||
if (flags & LOOKUP_SPECULATIVELY)
|
||
return NULL_TREE;
|
||
return error_mark_node;
|
||
}
|
||
|
||
if (conversion && ctor)
|
||
{
|
||
if (flags & LOOKUP_COMPLAIN)
|
||
error ("both constructor and type conversion operator apply");
|
||
if (flags & LOOKUP_SPECULATIVELY)
|
||
return NULL_TREE;
|
||
return error_mark_node;
|
||
}
|
||
else if (conversion)
|
||
return conversion;
|
||
else if (ctor)
|
||
{
|
||
ctor = build_cplus_new (type, ctor);
|
||
return ctor;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* If TYPE or TREE_TYPE (E) is not on the permanent_obstack,
|
||
then the it won't be hashed and hence compare as not equal,
|
||
even when it is. */
|
||
if (code == ARRAY_TYPE
|
||
&& TREE_TYPE (TREE_TYPE (e)) == TREE_TYPE (type)
|
||
&& index_type_equal (TYPE_DOMAIN (TREE_TYPE (e)), TYPE_DOMAIN (type)))
|
||
return e;
|
||
|
||
if (flags & LOOKUP_COMPLAIN)
|
||
cp_error ("conversion from `%T' to non-scalar type `%T' requested",
|
||
TREE_TYPE (expr), type);
|
||
if (flags & LOOKUP_SPECULATIVELY)
|
||
return NULL_TREE;
|
||
return error_mark_node;
|
||
}
|
||
|
||
/* Create an expression whose value is that of EXPR,
|
||
converted to type TYPE. The TREE_TYPE of the value
|
||
is always TYPE. This function implements all reasonable
|
||
conversions; callers should filter out those that are
|
||
not permitted by the language being compiled.
|
||
|
||
Most of this routine is from build_reinterpret_cast.
|
||
|
||
The backend cannot call cp_convert (what was convert) because
|
||
conversions to/from basetypes may involve memory references
|
||
(vbases) and adding or subtracting small values (multiple
|
||
inheritance), but it calls convert from the constant folding code
|
||
on subtrees of already build trees after it has ripped them apart.
|
||
|
||
Also, if we ever support range variables, we'll probably also have to
|
||
do a little bit more work. */
|
||
|
||
tree
|
||
convert (type, expr)
|
||
tree type, expr;
|
||
{
|
||
tree intype;
|
||
|
||
if (type == error_mark_node || expr == error_mark_node)
|
||
return error_mark_node;
|
||
|
||
intype = TREE_TYPE (expr);
|
||
|
||
if (POINTER_TYPE_P (type) && POINTER_TYPE_P (intype))
|
||
{
|
||
if (TREE_READONLY_DECL_P (expr))
|
||
expr = decl_constant_value (expr);
|
||
return fold (build1 (NOP_EXPR, type, expr));
|
||
}
|
||
|
||
return ocp_convert (type, expr, CONV_OLD_CONVERT,
|
||
LOOKUP_NORMAL|LOOKUP_NO_CONVERSION);
|
||
}
|
||
|
||
/* Like cp_convert, except permit conversions to take place which
|
||
are not normally allowed due to access restrictions
|
||
(such as conversion from sub-type to private super-type). */
|
||
|
||
tree
|
||
convert_force (type, expr, convtype)
|
||
tree type;
|
||
tree expr;
|
||
int convtype;
|
||
{
|
||
register tree e = expr;
|
||
register enum tree_code code = TREE_CODE (type);
|
||
|
||
if (code == REFERENCE_TYPE)
|
||
return fold (convert_to_reference (type, e, CONV_C_CAST, LOOKUP_COMPLAIN,
|
||
NULL_TREE));
|
||
else if (TREE_CODE (TREE_TYPE (e)) == REFERENCE_TYPE)
|
||
e = convert_from_reference (e);
|
||
|
||
if (code == POINTER_TYPE)
|
||
return fold (convert_to_pointer_force (type, e));
|
||
|
||
/* From typeck.c convert_for_assignment */
|
||
if (((TREE_CODE (TREE_TYPE (e)) == POINTER_TYPE && TREE_CODE (e) == ADDR_EXPR
|
||
&& TREE_CODE (TREE_TYPE (e)) == POINTER_TYPE
|
||
&& TREE_CODE (TREE_TYPE (TREE_TYPE (e))) == METHOD_TYPE)
|
||
|| integer_zerop (e)
|
||
|| TYPE_PTRMEMFUNC_P (TREE_TYPE (e)))
|
||
&& TYPE_PTRMEMFUNC_P (type))
|
||
{
|
||
/* compatible pointer to member functions. */
|
||
return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), e, 1);
|
||
}
|
||
|
||
return ocp_convert (type, e, CONV_C_CAST|convtype, LOOKUP_NORMAL);
|
||
}
|
||
|
||
/* Subroutine of build_type_conversion. */
|
||
|
||
static tree
|
||
build_type_conversion_1 (xtype, basetype, expr, typename, for_sure)
|
||
tree xtype, basetype;
|
||
tree expr;
|
||
tree typename;
|
||
int for_sure;
|
||
{
|
||
tree rval;
|
||
int flags;
|
||
|
||
if (for_sure == 0)
|
||
flags = LOOKUP_PROTECT|LOOKUP_ONLYCONVERTING;
|
||
else
|
||
flags = LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING;
|
||
|
||
rval = build_method_call (expr, typename, NULL_TREE, NULL_TREE, flags);
|
||
if (rval == error_mark_node)
|
||
{
|
||
if (for_sure == 0)
|
||
return NULL_TREE;
|
||
return error_mark_node;
|
||
}
|
||
|
||
if (IS_AGGR_TYPE (TREE_TYPE (rval)))
|
||
return rval;
|
||
|
||
if (warn_cast_qual
|
||
&& TREE_TYPE (xtype)
|
||
&& (TREE_READONLY (TREE_TYPE (TREE_TYPE (rval)))
|
||
> TREE_READONLY (TREE_TYPE (xtype))))
|
||
warning ("user-defined conversion casting away `const'");
|
||
return cp_convert (xtype, rval);
|
||
}
|
||
|
||
/* Convert an aggregate EXPR to type XTYPE. If a conversion
|
||
exists, return the attempted conversion. This may
|
||
return ERROR_MARK_NODE if the conversion is not
|
||
allowed (references private members, etc).
|
||
If no conversion exists, NULL_TREE is returned.
|
||
|
||
If (FOR_SURE & 1) is non-zero, then we allow this type conversion
|
||
to take place immediately. Otherwise, we build a SAVE_EXPR
|
||
which can be evaluated if the results are ever needed.
|
||
|
||
Changes to this functions should be mirrored in user_harshness.
|
||
|
||
FIXME: Ambiguity checking is wrong. Should choose one by the implicit
|
||
object parameter, or by the second standard conversion sequence if
|
||
that doesn't do it. This will probably wait for an overloading rewrite.
|
||
(jason 8/9/95) */
|
||
|
||
tree
|
||
build_type_conversion (code, xtype, expr, for_sure)
|
||
enum tree_code code;
|
||
tree xtype, expr;
|
||
int for_sure;
|
||
{
|
||
/* C++: check to see if we can convert this aggregate type
|
||
into the required type. */
|
||
tree basetype;
|
||
tree conv;
|
||
tree winner = NULL_TREE;
|
||
|
||
if (flag_ansi_overloading)
|
||
return build_user_type_conversion
|
||
(xtype, expr, for_sure ? LOOKUP_NORMAL : 0);
|
||
|
||
if (expr == error_mark_node)
|
||
return error_mark_node;
|
||
|
||
basetype = TREE_TYPE (expr);
|
||
if (TREE_CODE (basetype) == REFERENCE_TYPE)
|
||
basetype = TREE_TYPE (basetype);
|
||
|
||
basetype = TYPE_MAIN_VARIANT (basetype);
|
||
if (! TYPE_LANG_SPECIFIC (basetype) || ! TYPE_HAS_CONVERSION (basetype))
|
||
return NULL_TREE;
|
||
|
||
/* Do we have an exact match? */
|
||
{
|
||
tree typename = build_typename_overload (xtype);
|
||
if (lookup_fnfields (TYPE_BINFO (basetype), typename, 0))
|
||
return build_type_conversion_1 (xtype, basetype, expr, typename,
|
||
for_sure);
|
||
}
|
||
|
||
/* Nope; try looking for others. */
|
||
for (conv = lookup_conversions (basetype); conv; conv = TREE_CHAIN (conv))
|
||
{
|
||
tree cand = TREE_VALUE (conv);
|
||
|
||
if (winner && winner == cand)
|
||
continue;
|
||
|
||
if (can_convert (xtype, TREE_TYPE (TREE_TYPE (cand))))
|
||
{
|
||
if (winner)
|
||
{
|
||
if (for_sure)
|
||
{
|
||
cp_error ("ambiguous conversion from `%T' to `%T'", basetype,
|
||
xtype);
|
||
cp_error (" candidate conversions include `%D' and `%D'",
|
||
winner, cand);
|
||
}
|
||
return NULL_TREE;
|
||
}
|
||
else
|
||
winner = cand;
|
||
}
|
||
}
|
||
|
||
if (winner)
|
||
return build_type_conversion_1 (xtype, basetype, expr,
|
||
DECL_NAME (winner), for_sure);
|
||
|
||
return NULL_TREE;
|
||
}
|
||
|
||
/* Convert the given EXPR to one of a group of types suitable for use in an
|
||
expression. DESIRES is a combination of various WANT_* flags (q.v.)
|
||
which indicates which types are suitable. If COMPLAIN is 1, complain
|
||
about ambiguity; otherwise, the caller will deal with it. */
|
||
|
||
tree
|
||
build_expr_type_conversion (desires, expr, complain)
|
||
int desires;
|
||
tree expr;
|
||
int complain;
|
||
{
|
||
tree basetype = TREE_TYPE (expr);
|
||
tree conv;
|
||
tree winner = NULL_TREE;
|
||
|
||
if (TREE_CODE (basetype) == OFFSET_TYPE)
|
||
expr = resolve_offset_ref (expr);
|
||
expr = convert_from_reference (expr);
|
||
basetype = TREE_TYPE (expr);
|
||
|
||
if (! IS_AGGR_TYPE (basetype))
|
||
switch (TREE_CODE (basetype))
|
||
{
|
||
case INTEGER_TYPE:
|
||
if ((desires & WANT_NULL) && TREE_CODE (expr) == INTEGER_CST
|
||
&& integer_zerop (expr))
|
||
return expr;
|
||
/* else fall through... */
|
||
|
||
case BOOLEAN_TYPE:
|
||
return (desires & WANT_INT) ? expr : NULL_TREE;
|
||
case ENUMERAL_TYPE:
|
||
return (desires & WANT_ENUM) ? expr : NULL_TREE;
|
||
case REAL_TYPE:
|
||
return (desires & WANT_FLOAT) ? expr : NULL_TREE;
|
||
case POINTER_TYPE:
|
||
return (desires & WANT_POINTER) ? expr : NULL_TREE;
|
||
|
||
case FUNCTION_TYPE:
|
||
case ARRAY_TYPE:
|
||
return (desires & WANT_POINTER) ? default_conversion (expr)
|
||
: NULL_TREE;
|
||
default:
|
||
return NULL_TREE;
|
||
}
|
||
|
||
if (! TYPE_HAS_CONVERSION (basetype))
|
||
return NULL_TREE;
|
||
|
||
for (conv = lookup_conversions (basetype); conv; conv = TREE_CHAIN (conv))
|
||
{
|
||
int win = 0;
|
||
tree candidate;
|
||
tree cand = TREE_VALUE (conv);
|
||
|
||
if (winner && winner == cand)
|
||
continue;
|
||
|
||
candidate = TREE_TYPE (TREE_TYPE (cand));
|
||
if (TREE_CODE (candidate) == REFERENCE_TYPE)
|
||
candidate = TREE_TYPE (candidate);
|
||
|
||
switch (TREE_CODE (candidate))
|
||
{
|
||
case BOOLEAN_TYPE:
|
||
case INTEGER_TYPE:
|
||
win = (desires & WANT_INT); break;
|
||
case ENUMERAL_TYPE:
|
||
win = (desires & WANT_ENUM); break;
|
||
case REAL_TYPE:
|
||
win = (desires & WANT_FLOAT); break;
|
||
case POINTER_TYPE:
|
||
win = (desires & WANT_POINTER); break;
|
||
}
|
||
|
||
if (win)
|
||
{
|
||
if (winner)
|
||
{
|
||
if (complain)
|
||
{
|
||
cp_error ("ambiguous default type conversion from `%T'",
|
||
basetype);
|
||
cp_error (" candidate conversions include `%D' and `%D'",
|
||
winner, cand);
|
||
}
|
||
return error_mark_node;
|
||
}
|
||
else
|
||
winner = cand;
|
||
}
|
||
}
|
||
|
||
if (winner)
|
||
{
|
||
tree type = TREE_TYPE (TREE_TYPE (winner));
|
||
if (TREE_CODE (type) == REFERENCE_TYPE)
|
||
type = TREE_TYPE (type);
|
||
return build_type_conversion_1 (type, basetype, expr,
|
||
DECL_NAME (winner), 1);
|
||
}
|
||
|
||
return NULL_TREE;
|
||
}
|
||
|
||
/* Must convert two aggregate types to non-aggregate type.
|
||
Attempts to find a non-ambiguous, "best" type conversion.
|
||
|
||
Return 1 on success, 0 on failure.
|
||
|
||
@@ What are the real semantics of this supposed to be??? */
|
||
|
||
int
|
||
build_default_binary_type_conversion (code, arg1, arg2)
|
||
enum tree_code code;
|
||
tree *arg1, *arg2;
|
||
{
|
||
switch (code)
|
||
{
|
||
case MULT_EXPR:
|
||
case TRUNC_DIV_EXPR:
|
||
case CEIL_DIV_EXPR:
|
||
case FLOOR_DIV_EXPR:
|
||
case ROUND_DIV_EXPR:
|
||
case EXACT_DIV_EXPR:
|
||
*arg1 = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, *arg1, 0);
|
||
*arg2 = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, *arg2, 0);
|
||
break;
|
||
|
||
case TRUNC_MOD_EXPR:
|
||
case FLOOR_MOD_EXPR:
|
||
case LSHIFT_EXPR:
|
||
case RSHIFT_EXPR:
|
||
case BIT_AND_EXPR:
|
||
case BIT_XOR_EXPR:
|
||
case BIT_IOR_EXPR:
|
||
*arg1 = build_expr_type_conversion (WANT_INT | WANT_ENUM, *arg1, 0);
|
||
*arg2 = build_expr_type_conversion (WANT_INT | WANT_ENUM, *arg2, 0);
|
||
break;
|
||
|
||
case PLUS_EXPR:
|
||
{
|
||
tree a1, a2, p1, p2;
|
||
int wins;
|
||
|
||
a1 = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, *arg1, 0);
|
||
a2 = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, *arg2, 0);
|
||
p1 = build_expr_type_conversion (WANT_POINTER, *arg1, 0);
|
||
p2 = build_expr_type_conversion (WANT_POINTER, *arg2, 0);
|
||
|
||
wins = (a1 && a2) + (a1 && p2) + (p1 && a2);
|
||
|
||
if (wins > 1)
|
||
error ("ambiguous default type conversion for `operator +'");
|
||
|
||
if (a1 && a2)
|
||
*arg1 = a1, *arg2 = a2;
|
||
else if (a1 && p2)
|
||
*arg1 = a1, *arg2 = p2;
|
||
else
|
||
*arg1 = p1, *arg2 = a2;
|
||
break;
|
||
}
|
||
|
||
case MINUS_EXPR:
|
||
{
|
||
tree a1, a2, p1, p2;
|
||
int wins;
|
||
|
||
a1 = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, *arg1, 0);
|
||
a2 = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, *arg2, 0);
|
||
p1 = build_expr_type_conversion (WANT_POINTER, *arg1, 0);
|
||
p2 = build_expr_type_conversion (WANT_POINTER, *arg2, 0);
|
||
|
||
wins = (a1 && a2) + (p1 && p2) + (p1 && a2);
|
||
|
||
if (wins > 1)
|
||
error ("ambiguous default type conversion for `operator -'");
|
||
|
||
if (a1 && a2)
|
||
*arg1 = a1, *arg2 = a2;
|
||
else if (p1 && p2)
|
||
*arg1 = p1, *arg2 = p2;
|
||
else
|
||
*arg1 = p1, *arg2 = a2;
|
||
break;
|
||
}
|
||
|
||
case GT_EXPR:
|
||
case LT_EXPR:
|
||
case GE_EXPR:
|
||
case LE_EXPR:
|
||
case EQ_EXPR:
|
||
case NE_EXPR:
|
||
{
|
||
tree a1, a2, p1, p2;
|
||
int wins;
|
||
|
||
a1 = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, *arg1, 0);
|
||
a2 = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, *arg2, 0);
|
||
p1 = build_expr_type_conversion (WANT_POINTER | WANT_NULL, *arg1, 0);
|
||
p2 = build_expr_type_conversion (WANT_POINTER | WANT_NULL, *arg2, 0);
|
||
|
||
wins = (a1 && a2) + (p1 && p2);
|
||
|
||
if (wins > 1)
|
||
cp_error ("ambiguous default type conversion for `%O'", code);
|
||
|
||
if (a1 && a2)
|
||
*arg1 = a1, *arg2 = a2;
|
||
else
|
||
*arg1 = p1, *arg2 = p2;
|
||
break;
|
||
}
|
||
|
||
case TRUTH_ANDIF_EXPR:
|
||
case TRUTH_ORIF_EXPR:
|
||
*arg1 = cp_convert (boolean_type_node, *arg1);
|
||
*arg2 = cp_convert (boolean_type_node, *arg2);
|
||
break;
|
||
|
||
default:
|
||
*arg1 = NULL_TREE;
|
||
*arg2 = NULL_TREE;
|
||
}
|
||
|
||
if (*arg1 == error_mark_node || *arg2 == error_mark_node)
|
||
cp_error ("ambiguous default type conversion for `%O'", code);
|
||
|
||
if (*arg1 && *arg2)
|
||
return 1;
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Implements integral promotion (4.1) and float->double promotion. */
|
||
|
||
tree
|
||
type_promotes_to (type)
|
||
tree type;
|
||
{
|
||
int constp, volatilep;
|
||
|
||
if (type == error_mark_node)
|
||
return error_mark_node;
|
||
|
||
constp = TYPE_READONLY (type);
|
||
volatilep = TYPE_VOLATILE (type);
|
||
type = TYPE_MAIN_VARIANT (type);
|
||
|
||
/* bool always promotes to int (not unsigned), even if it's the same
|
||
size. */
|
||
if (type == boolean_type_node)
|
||
type = integer_type_node;
|
||
|
||
/* Normally convert enums to int, but convert wide enums to something
|
||
wider. */
|
||
else if (TREE_CODE (type) == ENUMERAL_TYPE
|
||
|| type == wchar_type_node)
|
||
{
|
||
int precision = MAX (TYPE_PRECISION (type),
|
||
TYPE_PRECISION (integer_type_node));
|
||
tree totype = type_for_size (precision, 0);
|
||
if (TREE_UNSIGNED (type)
|
||
&& ! int_fits_type_p (TYPE_MAX_VALUE (type), totype))
|
||
type = type_for_size (precision, 1);
|
||
else
|
||
type = totype;
|
||
}
|
||
else if (C_PROMOTING_INTEGER_TYPE_P (type))
|
||
{
|
||
/* Retain unsignedness if really not getting bigger. */
|
||
if (TREE_UNSIGNED (type)
|
||
&& TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
|
||
type = unsigned_type_node;
|
||
else
|
||
type = integer_type_node;
|
||
}
|
||
else if (type == float_type_node)
|
||
type = double_type_node;
|
||
|
||
return cp_build_type_variant (type, constp, volatilep);
|
||
}
|