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08db0e4d74
freebsd-skq/contrib/gcc/cp/call.c
kan 08db0e4d74 Gcc 3.3.1-release.
2003-08-22 02:56:07 +00:00

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/* Functions related to invoking methods and overloaded functions.
Copyright (C) 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 2003,
1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
Contributed by Michael Tiemann (tiemann@cygnus.com) and
modified by Brendan Kehoe (brendan@cygnus.com).
This file is part of GNU CC.
GNU CC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU CC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING. If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
/* High-level class interface. */
#include "config.h"
#include "system.h"
#include "tree.h"
#include "cp-tree.h"
#include "output.h"
#include "flags.h"
#include "rtl.h"
#include "toplev.h"
#include "expr.h"
#include "ggc.h"
#include "diagnostic.h"
extern int inhibit_warnings;
static tree build_field_call PARAMS ((tree, tree, tree));
static struct z_candidate * tourney PARAMS ((struct z_candidate *));
static int equal_functions PARAMS ((tree, tree));
static int joust PARAMS ((struct z_candidate *, struct z_candidate *, int));
static int compare_ics PARAMS ((tree, tree));
static tree build_over_call PARAMS ((struct z_candidate *, tree, int));
static tree build_java_interface_fn_ref PARAMS ((tree, tree));
#define convert_like(CONV, EXPR) \
convert_like_real ((CONV), (EXPR), NULL_TREE, 0, 0, \
/*issue_conversion_warnings=*/true)
#define convert_like_with_context(CONV, EXPR, FN, ARGNO) \
convert_like_real ((CONV), (EXPR), (FN), (ARGNO), 0, \
/*issue_conversion_warnings=*/true)
static tree convert_like_real (tree, tree, tree, int, int, bool);
static void op_error PARAMS ((enum tree_code, enum tree_code, tree, tree,
tree, const char *));
static tree build_object_call PARAMS ((tree, tree));
static tree resolve_args PARAMS ((tree));
static struct z_candidate * build_user_type_conversion_1
PARAMS ((tree, tree, int));
static void print_z_candidates PARAMS ((struct z_candidate *));
static tree build_this PARAMS ((tree));
static struct z_candidate * splice_viable PARAMS ((struct z_candidate *));
static int any_viable PARAMS ((struct z_candidate *));
static int any_strictly_viable PARAMS ((struct z_candidate *));
static struct z_candidate * add_template_candidate
PARAMS ((struct z_candidate **, tree, tree, tree, tree, tree,
tree, tree, int, unification_kind_t));
static struct z_candidate * add_template_candidate_real
PARAMS ((struct z_candidate **, tree, tree, tree, tree, tree,
tree, tree, int, tree, unification_kind_t));
static struct z_candidate * add_template_conv_candidate
PARAMS ((struct z_candidate **, tree, tree, tree, tree, tree, tree));
static void add_builtin_candidates
PARAMS ((struct z_candidate **, enum tree_code, enum tree_code,
tree, tree *, int));
static void add_builtin_candidate
PARAMS ((struct z_candidate **, enum tree_code, enum tree_code,
tree, tree, tree, tree *, tree *, int));
static int is_complete PARAMS ((tree));
static void build_builtin_candidate
PARAMS ((struct z_candidate **, tree, tree, tree, tree *, tree *,
int));
static struct z_candidate * add_conv_candidate
PARAMS ((struct z_candidate **, tree, tree, tree, tree, tree));
static struct z_candidate * add_function_candidate
(struct z_candidate **, tree, tree, tree, tree, tree, int);
static tree implicit_conversion PARAMS ((tree, tree, tree, int));
static tree standard_conversion PARAMS ((tree, tree, tree));
static tree reference_binding (tree, tree, tree, int);
static tree non_reference PARAMS ((tree));
static tree build_conv PARAMS ((enum tree_code, tree, tree));
static int is_subseq PARAMS ((tree, tree));
static tree maybe_handle_ref_bind PARAMS ((tree*));
static void maybe_handle_implicit_object PARAMS ((tree*));
static struct z_candidate *add_candidate
(struct z_candidate **, tree, tree, tree, tree, int);
static tree source_type PARAMS ((tree));
static void add_warning PARAMS ((struct z_candidate *, struct z_candidate *));
static int reference_related_p PARAMS ((tree, tree));
static int reference_compatible_p PARAMS ((tree, tree));
static tree convert_class_to_reference PARAMS ((tree, tree, tree));
static tree direct_reference_binding PARAMS ((tree, tree));
static int promoted_arithmetic_type_p PARAMS ((tree));
static tree conditional_conversion PARAMS ((tree, tree));
static tree call_builtin_trap PARAMS ((void));
static tree merge_conversion_sequences (tree, tree);
tree
build_vfield_ref (datum, type)
tree datum, type;
{
if (datum == error_mark_node)
return error_mark_node;
if (TREE_CODE (TREE_TYPE (datum)) == REFERENCE_TYPE)
datum = convert_from_reference (datum);
if (TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
&& !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (datum), type))
datum = convert_to_base (datum, type, /*check_access=*/false);
return build (COMPONENT_REF, TREE_TYPE (TYPE_VFIELD (type)),
datum, TYPE_VFIELD (type));
}
/* Build a call to a member of an object. I.e., one that overloads
operator ()(), or is a pointer-to-function or pointer-to-method. */
static tree
build_field_call (tree instance_ptr, tree decl, tree parms)
{
tree instance;
if (decl == error_mark_node || decl == NULL_TREE)
return decl;
if (TREE_CODE (decl) == FIELD_DECL || TREE_CODE (decl) == VAR_DECL)
{
/* If it's a field, try overloading operator (),
or calling if the field is a pointer-to-function. */
instance = build_indirect_ref (instance_ptr, NULL);
instance = build_class_member_access_expr (instance, decl,
/*access_path=*/NULL_TREE,
/*preserve_reference=*/false);
if (instance == error_mark_node)
return error_mark_node;
if (IS_AGGR_TYPE (TREE_TYPE (instance)))
return build_opfncall (CALL_EXPR, LOOKUP_NORMAL,
instance, parms, NULL_TREE);
else if (TREE_CODE (TREE_TYPE (instance)) == FUNCTION_TYPE
|| (TREE_CODE (TREE_TYPE (instance)) == POINTER_TYPE
&& (TREE_CODE (TREE_TYPE (TREE_TYPE (instance)))
== FUNCTION_TYPE)))
return build_function_call (instance, parms);
}
return NULL_TREE;
}
/* Returns nonzero iff the destructor name specified in NAME
(a BIT_NOT_EXPR) matches BASETYPE. The operand of NAME can take many
forms... */
int
check_dtor_name (basetype, name)
tree basetype, name;
{
name = TREE_OPERAND (name, 0);
/* Just accept something we've already complained about. */
if (name == error_mark_node)
return 1;
if (TREE_CODE (name) == TYPE_DECL)
name = TREE_TYPE (name);
else if (TYPE_P (name))
/* OK */;
else if (TREE_CODE (name) == IDENTIFIER_NODE)
{
if ((IS_AGGR_TYPE (basetype) && name == constructor_name (basetype))
|| (TREE_CODE (basetype) == ENUMERAL_TYPE
&& name == TYPE_IDENTIFIER (basetype)))
name = basetype;
else
name = get_type_value (name);
}
/* In the case of:
template <class T> struct S { ~S(); };
int i;
i.~S();
NAME will be a class template. */
else if (DECL_CLASS_TEMPLATE_P (name))
return 0;
else
abort ();
if (name && TYPE_MAIN_VARIANT (basetype) == TYPE_MAIN_VARIANT (name))
return 1;
return 0;
}
/* Build a method call of the form `EXP->SCOPES::NAME (PARMS)'.
This is how virtual function calls are avoided. */
tree
build_scoped_method_call (exp, basetype, name, parms)
tree exp, basetype, name, parms;
{
/* Because this syntactic form does not allow
a pointer to a base class to be `stolen',
we need not protect the derived->base conversion
that happens here.
@@ But we do have to check access privileges later. */
tree binfo, decl;
tree type = TREE_TYPE (exp);
if (type == error_mark_node
|| basetype == error_mark_node)
return error_mark_node;
if (processing_template_decl)
{
if (TREE_CODE (name) == BIT_NOT_EXPR
&& TREE_CODE (TREE_OPERAND (name, 0)) == IDENTIFIER_NODE)
{
tree type = get_aggr_from_typedef (TREE_OPERAND (name, 0), 0);
if (type)
name = build_min_nt (BIT_NOT_EXPR, type);
}
name = build_min_nt (SCOPE_REF, basetype, name);
return build_min_nt (METHOD_CALL_EXPR, name, exp, parms, NULL_TREE);
}
if (TREE_CODE (type) == REFERENCE_TYPE)
type = TREE_TYPE (type);
if (TREE_CODE (basetype) == TREE_VEC)
{
binfo = basetype;
basetype = BINFO_TYPE (binfo);
}
else
binfo = NULL_TREE;
/* Check the destructor call syntax. */
if (TREE_CODE (name) == BIT_NOT_EXPR)
{
/* We can get here if someone writes their destructor call like
`obj.NS::~T()'; this isn't really a scoped method call, so hand
it off. */
if (TREE_CODE (basetype) == NAMESPACE_DECL)
return build_method_call (exp, name, parms, NULL_TREE, LOOKUP_NORMAL);
if (! check_dtor_name (basetype, name))
error ("qualified type `%T' does not match destructor name `~%T'",
basetype, TREE_OPERAND (name, 0));
/* Destructors can be "called" for simple types; see 5.2.4 and 12.4 Note
that explicit ~int is caught in the parser; this deals with typedefs
and template parms. */
if (! IS_AGGR_TYPE (basetype))
{
if (TYPE_MAIN_VARIANT (type) != TYPE_MAIN_VARIANT (basetype))
error ("type of `%E' does not match destructor type `%T' (type was `%T')",
exp, basetype, type);
return cp_convert (void_type_node, exp);
}
}
if (TREE_CODE (basetype) == NAMESPACE_DECL)
{
error ("`%D' is a namespace", basetype);
return error_mark_node;
}
if (! is_aggr_type (basetype, 1))
return error_mark_node;
if (! IS_AGGR_TYPE (type))
{
error ("base object `%E' of scoped method call is of non-aggregate type `%T'",
exp, type);
return error_mark_node;
}
decl = build_scoped_ref (exp, basetype, &binfo);
if (binfo)
{
/* Call to a destructor. */
if (TREE_CODE (name) == BIT_NOT_EXPR)
{
if (! TYPE_HAS_DESTRUCTOR (TREE_TYPE (decl)))
return cp_convert (void_type_node, exp);
return build_delete (TREE_TYPE (decl), decl,
sfk_complete_destructor,
LOOKUP_NORMAL|LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR,
0);
}
/* Call to a method. */
return build_method_call (decl, name, parms, binfo,
LOOKUP_NORMAL|LOOKUP_NONVIRTUAL);
}
return error_mark_node;
}
/* We want the address of a function or method. We avoid creating a
pointer-to-member function. */
tree
build_addr_func (function)
tree function;
{
tree type = TREE_TYPE (function);
/* We have to do these by hand to avoid real pointer to member
functions. */
if (TREE_CODE (type) == METHOD_TYPE)
{
tree addr;
type = build_pointer_type (type);
if (!cxx_mark_addressable (function))
return error_mark_node;
addr = build1 (ADDR_EXPR, type, function);
/* Address of a static or external variable or function counts
as a constant */
if (staticp (function))
TREE_CONSTANT (addr) = 1;
function = addr;
}
else
function = default_conversion (function);
return function;
}
/* Build a CALL_EXPR, we can handle FUNCTION_TYPEs, METHOD_TYPEs, or
POINTER_TYPE to those. Note, pointer to member function types
(TYPE_PTRMEMFUNC_P) must be handled by our callers. */
tree
build_call (function, parms)
tree function, parms;
{
int is_constructor = 0;
int nothrow;
tree tmp;
tree decl;
tree result_type;
tree fntype;
function = build_addr_func (function);
if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
{
sorry ("unable to call pointer to member function here");
return error_mark_node;
}
fntype = TREE_TYPE (TREE_TYPE (function));
result_type = TREE_TYPE (fntype);
if (TREE_CODE (function) == ADDR_EXPR
&& TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
decl = TREE_OPERAND (function, 0);
else
decl = NULL_TREE;
/* We check both the decl and the type; a function may be known not to
throw without being declared throw(). */
nothrow = ((decl && TREE_NOTHROW (decl))
|| TYPE_NOTHROW_P (TREE_TYPE (TREE_TYPE (function))));
if (decl && TREE_THIS_VOLATILE (decl) && cfun)
current_function_returns_abnormally = 1;
if (decl && TREE_DEPRECATED (decl))
warn_deprecated_use (decl);
require_complete_eh_spec_types (fntype, decl);
if (decl && DECL_CONSTRUCTOR_P (decl))
is_constructor = 1;
if (decl && ! TREE_USED (decl))
{
/* We invoke build_call directly for several library functions.
These may have been declared normally if we're building libgcc,
so we can't just check DECL_ARTIFICIAL. */
if (DECL_ARTIFICIAL (decl)
|| !strncmp (IDENTIFIER_POINTER (DECL_NAME (decl)), "__", 2))
mark_used (decl);
else
abort ();
}
/* Don't pass empty class objects by value. This is useful
for tags in STL, which are used to control overload resolution.
We don't need to handle other cases of copying empty classes. */
if (! decl || ! DECL_BUILT_IN (decl))
for (tmp = parms; tmp; tmp = TREE_CHAIN (tmp))
if (is_empty_class (TREE_TYPE (TREE_VALUE (tmp)))
&& ! TREE_ADDRESSABLE (TREE_TYPE (TREE_VALUE (tmp))))
{
tree t = build (EMPTY_CLASS_EXPR, TREE_TYPE (TREE_VALUE (tmp)));
TREE_VALUE (tmp) = build (COMPOUND_EXPR, TREE_TYPE (t),
TREE_VALUE (tmp), t);
}
function = build_nt (CALL_EXPR, function, parms, NULL_TREE);
TREE_HAS_CONSTRUCTOR (function) = is_constructor;
TREE_TYPE (function) = result_type;
TREE_SIDE_EFFECTS (function) = 1;
TREE_NOTHROW (function) = nothrow;
return function;
}
/* Build something of the form ptr->method (args)
or object.method (args). This can also build
calls to constructors, and find friends.
Member functions always take their class variable
as a pointer.
INSTANCE is a class instance.
NAME is the name of the method desired, usually an IDENTIFIER_NODE.
PARMS help to figure out what that NAME really refers to.
BASETYPE_PATH, if non-NULL, contains a chain from the type of INSTANCE
down to the real instance type to use for access checking. We need this
information to get protected accesses correct. This parameter is used
by build_member_call.
FLAGS is the logical disjunction of zero or more LOOKUP_
flags. See cp-tree.h for more info.
If this is all OK, calls build_function_call with the resolved
member function.
This function must also handle being called to perform
initialization, promotion/coercion of arguments, and
instantiation of default parameters.
Note that NAME may refer to an instance variable name. If
`operator()()' is defined for the type of that field, then we return
that result. */
#ifdef GATHER_STATISTICS
extern int n_build_method_call;
#endif
tree
build_method_call (instance, name, parms, basetype_path, flags)
tree instance, name, parms, basetype_path;
int flags;
{
tree fn;
tree object_type;
tree template_args = NULL_TREE;
bool has_template_args = false;
#ifdef GATHER_STATISTICS
n_build_method_call++;
#endif
if (instance == error_mark_node
|| name == error_mark_node
|| parms == error_mark_node
|| (instance && TREE_TYPE (instance) == error_mark_node))
return error_mark_node;
if (processing_template_decl)
{
/* We need to process template parm names here so that tsubst catches
them properly. Other type names can wait. */
if (TREE_CODE (name) == BIT_NOT_EXPR)
{
tree type = NULL_TREE;
if (TREE_CODE (TREE_OPERAND (name, 0)) == IDENTIFIER_NODE)
type = get_aggr_from_typedef (TREE_OPERAND (name, 0), 0);
else if (TREE_CODE (TREE_OPERAND (name, 0)) == TYPE_DECL)
type = TREE_TYPE (TREE_OPERAND (name, 0));
if (type && TREE_CODE (type) == TEMPLATE_TYPE_PARM)
name = build_min_nt (BIT_NOT_EXPR, type);
}
return build_min_nt (METHOD_CALL_EXPR, name, instance, parms, NULL_TREE);
}
if (TREE_CODE (instance) == OFFSET_REF)
instance = resolve_offset_ref (instance);
if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
instance = convert_from_reference (instance);
object_type = TREE_TYPE (instance);
if (TREE_CODE (name) == BIT_NOT_EXPR)
{
tree instance_ptr;
if (parms)
error ("destructors take no parameters");
if (! check_dtor_name (object_type, name))
error
("destructor name `~%T' does not match type `%T' of expression",
TREE_OPERAND (name, 0), object_type);
/* The destructor type must be complete. */
object_type = complete_type_or_else (object_type, NULL_TREE);
if (!object_type || object_type == error_mark_node)
return error_mark_node;
if (! TYPE_HAS_DESTRUCTOR (object_type))
return cp_convert (void_type_node, instance);
instance = default_conversion (instance);
instance_ptr = build_unary_op (ADDR_EXPR, instance, 0);
return build_delete (build_pointer_type (object_type),
instance_ptr, sfk_complete_destructor,
LOOKUP_NORMAL|LOOKUP_DESTRUCTOR, 0);
}
if (!CLASS_TYPE_P (object_type))
{
if ((flags & LOOKUP_COMPLAIN)
&& TREE_TYPE (instance) != error_mark_node)
error ("request for member `%D' in `%E', which is of non-aggregate type `%T'",
name, instance, object_type);
return error_mark_node;
}
if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
{
template_args = TREE_OPERAND (name, 1);
has_template_args = true;
name = TREE_OPERAND (name, 0);
}
if (TREE_CODE (name) == OVERLOAD)
name = DECL_NAME (get_first_fn (name));
else if (TREE_CODE (name) == LOOKUP_EXPR)
name = TREE_OPERAND (name, 0);
else if (DECL_P (name))
name = DECL_NAME (name);
if (has_template_args)
fn = lookup_fnfields (object_type, name, /*protect=*/2);
else
fn = lookup_member (object_type, name, /*protect=*/2, /*want_type=*/0);
if (fn && TREE_CODE (fn) == TREE_LIST && !BASELINK_P (fn))
{
error ("request for member `%D' is ambiguous", name);
print_candidates (fn);
return error_mark_node;
}
/* If the name could not be found, issue an error. */
if (!fn)
{
unqualified_name_lookup_error (name);
return error_mark_node;
}
if (BASELINK_P (fn) && has_template_args)
BASELINK_FUNCTIONS (fn)
= build_nt (TEMPLATE_ID_EXPR,
BASELINK_FUNCTIONS (fn),
template_args);
if (BASELINK_P (fn) && basetype_path)
BASELINK_ACCESS_BINFO (fn) = basetype_path;
return build_new_method_call (instance, fn, parms,
/*conversion_path=*/NULL_TREE, flags);
}
/* New overloading code. */
struct z_candidate GTY(()) {
/* The FUNCTION_DECL that will be called if this candidate is
selected by overload resolution. */
tree fn;
tree convs;
tree second_conv;
int viable;
/* If FN is a member function, the binfo indicating the path used to
qualify the name of FN at the call site. This path is used to
determine whether or not FN is accessible if it is selected by
overload resolution. The DECL_CONTEXT of FN will always be a
(possibly improper) base of this binfo. */
tree access_path;
/* If FN is a non-static member function, the binfo indicating the
subobject to which the `this' pointer should be converted if FN
is selected by overload resolution. The type pointed to the by
the `this' pointer must correspond to the most derived class
indicated by the CONVERSION_PATH. */
tree conversion_path;
tree template;
tree warnings;
struct z_candidate *next;
};
#define IDENTITY_RANK 0
#define EXACT_RANK 1
#define PROMO_RANK 2
#define STD_RANK 3
#define PBOOL_RANK 4
#define USER_RANK 5
#define ELLIPSIS_RANK 6
#define BAD_RANK 7
#define ICS_RANK(NODE) \
(ICS_BAD_FLAG (NODE) ? BAD_RANK \
: ICS_ELLIPSIS_FLAG (NODE) ? ELLIPSIS_RANK \
: ICS_USER_FLAG (NODE) ? USER_RANK \
: ICS_STD_RANK (NODE))
#define ICS_STD_RANK(NODE) TREE_COMPLEXITY (NODE)
#define ICS_USER_FLAG(NODE) TREE_LANG_FLAG_0 (NODE)
#define ICS_ELLIPSIS_FLAG(NODE) TREE_LANG_FLAG_1 (NODE)
#define ICS_THIS_FLAG(NODE) TREE_LANG_FLAG_2 (NODE)
#define ICS_BAD_FLAG(NODE) TREE_LANG_FLAG_3 (NODE)
/* In a REF_BIND or a BASE_CONV, this indicates that a temporary
should be created to hold the result of the conversion. */
#define NEED_TEMPORARY_P(NODE) TREE_LANG_FLAG_4 (NODE)
#define USER_CONV_CAND(NODE) WRAPPER_ZC (TREE_OPERAND (NODE, 1))
#define USER_CONV_FN(NODE) (USER_CONV_CAND (NODE)->fn)
int
null_ptr_cst_p (t)
tree t;
{
/* [conv.ptr]
A null pointer constant is an integral constant expression
(_expr.const_) rvalue of integer type that evaluates to zero. */
if (t == null_node
|| (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)) && integer_zerop (t)))
return 1;
return 0;
}
/* Returns nonzero if PARMLIST consists of only default parms and/or
ellipsis. */
int
sufficient_parms_p (parmlist)
tree parmlist;
{
for (; parmlist && parmlist != void_list_node;
parmlist = TREE_CHAIN (parmlist))
if (!TREE_PURPOSE (parmlist))
return 0;
return 1;
}
static tree
build_conv (code, type, from)
enum tree_code code;
tree type, from;
{
tree t;
int rank = ICS_STD_RANK (from);
/* We can't use buildl1 here because CODE could be USER_CONV, which
takes two arguments. In that case, the caller is responsible for
filling in the second argument. */
t = make_node (code);
TREE_TYPE (t) = type;
TREE_OPERAND (t, 0) = from;
switch (code)
{
case PTR_CONV:
case PMEM_CONV:
case BASE_CONV:
case STD_CONV:
if (rank < STD_RANK)
rank = STD_RANK;
break;
case QUAL_CONV:
if (rank < EXACT_RANK)
rank = EXACT_RANK;
default:
break;
}
ICS_STD_RANK (t) = rank;
ICS_USER_FLAG (t) = (code == USER_CONV || ICS_USER_FLAG (from));
ICS_BAD_FLAG (t) = ICS_BAD_FLAG (from);
return t;
}
/* If T is a REFERENCE_TYPE return the type to which T refers.
Otherwise, return T itself. */
static tree
non_reference (t)
tree t;
{
if (TREE_CODE (t) == REFERENCE_TYPE)
t = TREE_TYPE (t);
return t;
}
tree
strip_top_quals (t)
tree t;
{
if (TREE_CODE (t) == ARRAY_TYPE)
return t;
return TYPE_MAIN_VARIANT (t);
}
/* Returns the standard conversion path (see [conv]) from type FROM to type
TO, if any. For proper handling of null pointer constants, you must
also pass the expression EXPR to convert from. */
static tree
standard_conversion (to, from, expr)
tree to, from, expr;
{
enum tree_code fcode, tcode;
tree conv;
int fromref = 0;
if (TREE_CODE (to) == REFERENCE_TYPE)
to = TREE_TYPE (to);
if (TREE_CODE (from) == REFERENCE_TYPE)
{
fromref = 1;
from = TREE_TYPE (from);
}
to = strip_top_quals (to);
from = strip_top_quals (from);
if ((TYPE_PTRFN_P (to) || TYPE_PTRMEMFUNC_P (to))
&& expr && type_unknown_p (expr))
{
expr = instantiate_type (to, expr, tf_none);
if (expr == error_mark_node)
return NULL_TREE;
from = TREE_TYPE (expr);
}
fcode = TREE_CODE (from);
tcode = TREE_CODE (to);
conv = build1 (IDENTITY_CONV, from, expr);
if (fcode == FUNCTION_TYPE)
{
from = build_pointer_type (from);
fcode = TREE_CODE (from);
conv = build_conv (LVALUE_CONV, from, conv);
}
else if (fcode == ARRAY_TYPE)
{
from = build_pointer_type (TREE_TYPE (from));
fcode = TREE_CODE (from);
conv = build_conv (LVALUE_CONV, from, conv);
}
else if (fromref || (expr && lvalue_p (expr)))
conv = build_conv (RVALUE_CONV, from, conv);
/* Allow conversion between `__complex__' data types */
if (tcode == COMPLEX_TYPE && fcode == COMPLEX_TYPE)
{
/* The standard conversion sequence to convert FROM to TO is
the standard conversion sequence to perform componentwise
conversion. */
tree part_conv = standard_conversion
(TREE_TYPE (to), TREE_TYPE (from), NULL_TREE);
if (part_conv)
{
conv = build_conv (TREE_CODE (part_conv), to, conv);
ICS_STD_RANK (conv) = ICS_STD_RANK (part_conv);
}
else
conv = NULL_TREE;
return conv;
}
if (same_type_p (from, to))
return conv;
if ((tcode == POINTER_TYPE || TYPE_PTRMEMFUNC_P (to))
&& expr && null_ptr_cst_p (expr))
{
conv = build_conv (STD_CONV, to, conv);
}
else if ((tcode == INTEGER_TYPE && fcode == POINTER_TYPE)
|| (tcode == POINTER_TYPE && fcode == INTEGER_TYPE))
{
/* For backwards brain damage compatibility, allow interconversion of
pointers and integers with a pedwarn. */
conv = build_conv (STD_CONV, to, conv);
ICS_BAD_FLAG (conv) = 1;
}
else if (tcode == ENUMERAL_TYPE && fcode == INTEGER_TYPE
&& TYPE_PRECISION (to) == TYPE_PRECISION (from))
{
/* For backwards brain damage compatibility, allow interconversion of
enums and integers with a pedwarn. */
conv = build_conv (STD_CONV, to, conv);
ICS_BAD_FLAG (conv) = 1;
}
else if (tcode == POINTER_TYPE && fcode == POINTER_TYPE)
{
enum tree_code ufcode = TREE_CODE (TREE_TYPE (from));
enum tree_code utcode = TREE_CODE (TREE_TYPE (to));
if (same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (from),
TREE_TYPE (to)))
;
else if (utcode == VOID_TYPE && ufcode != OFFSET_TYPE
&& ufcode != FUNCTION_TYPE)
{
from = build_pointer_type
(cp_build_qualified_type (void_type_node,
cp_type_quals (TREE_TYPE (from))));
conv = build_conv (PTR_CONV, from, conv);
}
else if (ufcode == OFFSET_TYPE && utcode == OFFSET_TYPE)
{
tree fbase = TYPE_OFFSET_BASETYPE (TREE_TYPE (from));
tree tbase = TYPE_OFFSET_BASETYPE (TREE_TYPE (to));
if (DERIVED_FROM_P (fbase, tbase)
&& (same_type_ignoring_top_level_qualifiers_p
(TREE_TYPE (TREE_TYPE (from)),
TREE_TYPE (TREE_TYPE (to)))))
{
from = build_ptrmem_type (tbase, TREE_TYPE (TREE_TYPE (from)));
conv = build_conv (PMEM_CONV, from, conv);
}
}
else if (IS_AGGR_TYPE (TREE_TYPE (from))
&& IS_AGGR_TYPE (TREE_TYPE (to)))
{
if (DERIVED_FROM_P (TREE_TYPE (to), TREE_TYPE (from)))
{
from =
cp_build_qualified_type (TREE_TYPE (to),
cp_type_quals (TREE_TYPE (from)));
from = build_pointer_type (from);
conv = build_conv (PTR_CONV, from, conv);
}
}
if (same_type_p (from, to))
/* OK */;
else if (comp_ptr_ttypes (TREE_TYPE (to), TREE_TYPE (from)))
conv = build_conv (QUAL_CONV, to, conv);
else if (expr && string_conv_p (to, expr, 0))
/* converting from string constant to char *. */
conv = build_conv (QUAL_CONV, to, conv);
else if (ptr_reasonably_similar (TREE_TYPE (to), TREE_TYPE (from)))
{
conv = build_conv (PTR_CONV, to, conv);
ICS_BAD_FLAG (conv) = 1;
}
else
return 0;
from = to;
}
else if (TYPE_PTRMEMFUNC_P (to) && TYPE_PTRMEMFUNC_P (from))
{
tree fromfn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (from));
tree tofn = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (to));
tree fbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (fromfn)));
tree tbase = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (tofn)));
if (!DERIVED_FROM_P (fbase, tbase)
|| !same_type_p (TREE_TYPE (fromfn), TREE_TYPE (tofn))
|| !compparms (TREE_CHAIN (TYPE_ARG_TYPES (fromfn)),
TREE_CHAIN (TYPE_ARG_TYPES (tofn)))
|| cp_type_quals (fbase) != cp_type_quals (tbase))
return 0;
from = cp_build_qualified_type (tbase, cp_type_quals (fbase));
from = build_cplus_method_type (from, TREE_TYPE (fromfn),
TREE_CHAIN (TYPE_ARG_TYPES (fromfn)));
from = build_ptrmemfunc_type (build_pointer_type (from));
conv = build_conv (PMEM_CONV, from, conv);
}
else if (tcode == BOOLEAN_TYPE)
{
if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE
|| fcode == POINTER_TYPE || TYPE_PTRMEMFUNC_P (from)))
return 0;
conv = build_conv (STD_CONV, to, conv);
if (fcode == POINTER_TYPE
|| (TYPE_PTRMEMFUNC_P (from) && ICS_STD_RANK (conv) < PBOOL_RANK))
ICS_STD_RANK (conv) = PBOOL_RANK;
}
/* We don't check for ENUMERAL_TYPE here because there are no standard
conversions to enum type. */
else if (tcode == INTEGER_TYPE || tcode == BOOLEAN_TYPE
|| tcode == REAL_TYPE)
{
if (! (INTEGRAL_CODE_P (fcode) || fcode == REAL_TYPE))
return 0;
conv = build_conv (STD_CONV, to, conv);
/* Give this a better rank if it's a promotion. */
if (to == type_promotes_to (from)
&& ICS_STD_RANK (TREE_OPERAND (conv, 0)) <= PROMO_RANK)
ICS_STD_RANK (conv) = PROMO_RANK;
}
else if (IS_AGGR_TYPE (to) && IS_AGGR_TYPE (from)
&& is_properly_derived_from (from, to))
{
if (TREE_CODE (conv) == RVALUE_CONV)
conv = TREE_OPERAND (conv, 0);
conv = build_conv (BASE_CONV, to, conv);
/* The derived-to-base conversion indicates the initialization
of a parameter with base type from an object of a derived
type. A temporary object is created to hold the result of
the conversion. */
NEED_TEMPORARY_P (conv) = 1;
}
else
return 0;
return conv;
}
/* Returns nonzero if T1 is reference-related to T2. */
static int
reference_related_p (t1, t2)
tree t1;
tree t2;
{
t1 = TYPE_MAIN_VARIANT (t1);
t2 = TYPE_MAIN_VARIANT (t2);
/* [dcl.init.ref]
Given types "cv1 T1" and "cv2 T2," "cv1 T1" is reference-related
to "cv2 T2" if T1 is the same type as T2, or T1 is a base class
of T2. */
return (same_type_p (t1, t2)
|| (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
&& DERIVED_FROM_P (t1, t2)));
}
/* Returns nonzero if T1 is reference-compatible with T2. */
static int
reference_compatible_p (t1, t2)
tree t1;
tree t2;
{
/* [dcl.init.ref]
"cv1 T1" is reference compatible with "cv2 T2" if T1 is
reference-related to T2 and cv1 is the same cv-qualification as,
or greater cv-qualification than, cv2. */
return (reference_related_p (t1, t2)
&& at_least_as_qualified_p (t1, t2));
}
/* Determine whether or not the EXPR (of class type S) can be
converted to T as in [over.match.ref]. */
static tree
convert_class_to_reference (t, s, expr)
tree t;
tree s;
tree expr;
{
tree conversions;
tree arglist;
tree conv;
tree reference_type;
struct z_candidate *candidates;
struct z_candidate *cand;
conversions = lookup_conversions (s);
if (!conversions)
return NULL_TREE;
/* [over.match.ref]
Assuming that "cv1 T" is the underlying type of the reference
being initialized, and "cv S" is the type of the initializer
expression, with S a class type, the candidate functions are
selected as follows:
--The conversion functions of S and its base classes are
considered. Those that are not hidden within S and yield type
"reference to cv2 T2", where "cv1 T" is reference-compatible
(_dcl.init.ref_) with "cv2 T2", are candidate functions.
The argument list has one argument, which is the initializer
expression. */
candidates = 0;
/* Conceptually, we should take the address of EXPR and put it in
the argument list. Unfortunately, however, that can result in
error messages, which we should not issue now because we are just
trying to find a conversion operator. Therefore, we use NULL,
cast to the appropriate type. */
arglist = build_int_2 (0, 0);
TREE_TYPE (arglist) = build_pointer_type (s);
arglist = build_tree_list (NULL_TREE, arglist);
reference_type = build_reference_type (t);
while (conversions)
{
tree fns = TREE_VALUE (conversions);
for (; fns; fns = OVL_NEXT (fns))
{
tree f = OVL_CURRENT (fns);
tree t2 = TREE_TYPE (TREE_TYPE (f));
cand = NULL;
/* If this is a template function, try to get an exact
match. */
if (TREE_CODE (f) == TEMPLATE_DECL)
{
cand = add_template_candidate (&candidates,
f, s,
NULL_TREE,
arglist,
reference_type,
TYPE_BINFO (s),
TREE_PURPOSE (conversions),
LOOKUP_NORMAL,
DEDUCE_CONV);
if (cand)
{
/* Now, see if the conversion function really returns
an lvalue of the appropriate type. From the
point of view of unification, simply returning an
rvalue of the right type is good enough. */
f = cand->fn;
t2 = TREE_TYPE (TREE_TYPE (f));
if (TREE_CODE (t2) != REFERENCE_TYPE
|| !reference_compatible_p (t, TREE_TYPE (t2)))
{
candidates = candidates->next;
cand = NULL;
}
}
}
else if (TREE_CODE (t2) == REFERENCE_TYPE
&& reference_compatible_p (t, TREE_TYPE (t2)))
cand = add_function_candidate (&candidates, f, s, arglist,
TYPE_BINFO (s),
TREE_PURPOSE (conversions),
LOOKUP_NORMAL);
if (cand)
/* Build a standard conversion sequence indicating the
binding from the reference type returned by the
function to the desired REFERENCE_TYPE. */
cand->second_conv
= (direct_reference_binding
(reference_type,
build1 (IDENTITY_CONV,
TREE_TYPE (TREE_TYPE (TREE_TYPE (cand->fn))),
NULL_TREE)));
}
conversions = TREE_CHAIN (conversions);
}
/* If none of the conversion functions worked out, let our caller
know. */
if (!any_viable (candidates))
return NULL_TREE;
candidates = splice_viable (candidates);
cand = tourney (candidates);
if (!cand)
return NULL_TREE;
/* Build a user-defined conversion sequence representing the
conversion. */
conv = build_conv (USER_CONV,
TREE_TYPE (TREE_TYPE (cand->fn)),
build1 (IDENTITY_CONV, TREE_TYPE (expr), expr));
TREE_OPERAND (conv, 1) = build_zc_wrapper (cand);
/* Merge it with the standard conversion sequence from the
conversion function's return type to the desired type. */
cand->second_conv = merge_conversion_sequences (conv, cand->second_conv);
if (cand->viable == -1)
ICS_BAD_FLAG (conv) = 1;
return cand->second_conv;
}
/* A reference of the indicated TYPE is being bound directly to the
expression represented by the implicit conversion sequence CONV.
Return a conversion sequence for this binding. */
static tree
direct_reference_binding (type, conv)
tree type;
tree conv;
{
tree t;
my_friendly_assert (TREE_CODE (type) == REFERENCE_TYPE, 20030306);
my_friendly_assert (TREE_CODE (TREE_TYPE (conv)) != REFERENCE_TYPE,
20030306);
t = TREE_TYPE (type);
/* [over.ics.rank]
When a parameter of reference type binds directly
(_dcl.init.ref_) to an argument expression, the implicit
conversion sequence is the identity conversion, unless the
argument expression has a type that is a derived class of the
parameter type, in which case the implicit conversion sequence is
a derived-to-base Conversion.
If the parameter binds directly to the result of applying a
conversion function to the argument expression, the implicit
conversion sequence is a user-defined conversion sequence
(_over.ics.user_), with the second standard conversion sequence
either an identity conversion or, if the conversion function
returns an entity of a type that is a derived class of the
parameter type, a derived-to-base conversion. */
if (!same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (conv)))
{
/* Represent the derived-to-base conversion. */
conv = build_conv (BASE_CONV, t, conv);
/* We will actually be binding to the base-class subobject in
the derived class, so we mark this conversion appropriately.
That way, convert_like knows not to generate a temporary. */
NEED_TEMPORARY_P (conv) = 0;
}
return build_conv (REF_BIND, type, conv);
}
/* Returns the conversion path from type FROM to reference type TO for
purposes of reference binding. For lvalue binding, either pass a
reference type to FROM or an lvalue expression to EXPR. If the
reference will be bound to a temporary, NEED_TEMPORARY_P is set for
the conversion returned. */
static tree
reference_binding (tree rto, tree rfrom, tree expr, int flags)
{
tree conv = NULL_TREE;
tree to = TREE_TYPE (rto);
tree from = rfrom;
int related_p;
int compatible_p;
cp_lvalue_kind lvalue_p = clk_none;
if (TREE_CODE (to) == FUNCTION_TYPE && expr && type_unknown_p (expr))
{
expr = instantiate_type (to, expr, tf_none);
if (expr == error_mark_node)
return NULL_TREE;
from = TREE_TYPE (expr);
}
if (TREE_CODE (from) == REFERENCE_TYPE)
{
/* Anything with reference type is an lvalue. */
lvalue_p = clk_ordinary;
from = TREE_TYPE (from);
}
else if (expr)
lvalue_p = real_lvalue_p (expr);
/* Figure out whether or not the types are reference-related and
reference compatible. We have do do this after stripping
references from FROM. */
related_p = reference_related_p (to, from);
compatible_p = reference_compatible_p (to, from);
if (lvalue_p && compatible_p)
{
/* [dcl.init.ref]
If the initializer expression
-- is an lvalue (but not an lvalue for a bit-field), and "cv1 T1"
is reference-compatible with "cv2 T2,"
the reference is bound directly to the initializer exprssion
lvalue. */
conv = build1 (IDENTITY_CONV, from, expr);
conv = direct_reference_binding (rto, conv);
if ((lvalue_p & clk_bitfield) != 0
&& CP_TYPE_CONST_NON_VOLATILE_P (to))
/* For the purposes of overload resolution, we ignore the fact
this expression is a bitfield. (In particular,
[over.ics.ref] says specifically that a function with a
non-const reference parameter is viable even if the
argument is a bitfield.)
However, when we actually call the function we must create
a temporary to which to bind the reference. If the
reference is volatile, or isn't const, then we cannot make
a temporary, so we just issue an error when the conversion
actually occurs. */
NEED_TEMPORARY_P (conv) = 1;
return conv;
}
else if (CLASS_TYPE_P (from) && !(flags & LOOKUP_NO_CONVERSION))
{
/* [dcl.init.ref]
If the initializer exprsesion
-- has a class type (i.e., T2 is a class type) can be
implicitly converted to an lvalue of type "cv3 T3," where
"cv1 T1" is reference-compatible with "cv3 T3". (this
conversion is selected by enumerating the applicable
conversion functions (_over.match.ref_) and choosing the
best one through overload resolution. (_over.match_).
the reference is bound to the lvalue result of the conversion
in the second case. */
conv = convert_class_to_reference (to, from, expr);
if (conv)
return conv;
}
/* From this point on, we conceptually need temporaries, even if we
elide them. Only the cases above are "direct bindings". */
if (flags & LOOKUP_NO_TEMP_BIND)
return NULL_TREE;
/* [over.ics.rank]
When a parameter of reference type is not bound directly to an
argument expression, the conversion sequence is the one required
to convert the argument expression to the underlying type of the
reference according to _over.best.ics_. Conceptually, this
conversion sequence corresponds to copy-initializing a temporary
of the underlying type with the argument expression. Any
difference in top-level cv-qualification is subsumed by the
initialization itself and does not constitute a conversion. */
/* [dcl.init.ref]
Otherwise, the reference shall be to a non-volatile const type. */
if (!CP_TYPE_CONST_NON_VOLATILE_P (to))
return NULL_TREE;
/* [dcl.init.ref]
If the initializer expression is an rvalue, with T2 a class type,
and "cv1 T1" is reference-compatible with "cv2 T2", the reference
is bound in one of the following ways:
-- The reference is bound to the object represented by the rvalue
or to a sub-object within that object.
-- ...
We use the first alternative. The implicit conversion sequence
is supposed to be same as we would obtain by generating a
temporary. Fortunately, if the types are reference compatible,
then this is either an identity conversion or the derived-to-base
conversion, just as for direct binding. */
if (CLASS_TYPE_P (from) && compatible_p)
{
conv = build1 (IDENTITY_CONV, from, expr);
return direct_reference_binding (rto, conv);
}
/* [dcl.init.ref]
Otherwise, a temporary of type "cv1 T1" is created and
initialized from the initializer expression using the rules for a
non-reference copy initialization. If T1 is reference-related to
T2, cv1 must be the same cv-qualification as, or greater
cv-qualification than, cv2; otherwise, the program is ill-formed. */
if (related_p && !at_least_as_qualified_p (to, from))
return NULL_TREE;
conv = implicit_conversion (to, from, expr, flags);
if (!conv)
return NULL_TREE;
conv = build_conv (REF_BIND, rto, conv);
/* This reference binding, unlike those above, requires the
creation of a temporary. */
NEED_TEMPORARY_P (conv) = 1;
return conv;
}
/* Returns the implicit conversion sequence (see [over.ics]) from type FROM
to type TO. The optional expression EXPR may affect the conversion.
FLAGS are the usual overloading flags. Only LOOKUP_NO_CONVERSION is
significant. */
static tree
implicit_conversion (to, from, expr, flags)
tree to, from, expr;
int flags;
{
tree conv;
/* Resolve expressions like `A::p' that we thought might become
pointers-to-members. */
if (expr && TREE_CODE (expr) == OFFSET_REF)
{
expr = resolve_offset_ref (expr);
from = TREE_TYPE (expr);
}
if (from == error_mark_node || to == error_mark_node
|| expr == error_mark_node)
return NULL_TREE;
if (TREE_CODE (to) == REFERENCE_TYPE)
conv = reference_binding (to, from, expr, flags);
else
conv = standard_conversion (to, from, expr);
if (conv)
;
else if (expr != NULL_TREE
&& (IS_AGGR_TYPE (from)
|| IS_AGGR_TYPE (to))
&& (flags & LOOKUP_NO_CONVERSION) == 0)
{
struct z_candidate *cand;
cand = build_user_type_conversion_1
(to, expr, LOOKUP_ONLYCONVERTING);
if (cand)
conv = cand->second_conv;
/* We used to try to bind a reference to a temporary here, but that
is now handled by the recursive call to this function at the end
of reference_binding. */
}
return conv;
}
/* Add a new entry to the list of candidates. Used by the add_*_candidate
functions. */
static struct z_candidate *
add_candidate (struct z_candidate **candidates,
tree fn, tree convs, tree access_path, tree
conversion_path, int viable)
{
struct z_candidate *cand
= (struct z_candidate *) ggc_alloc_cleared (sizeof (struct z_candidate));
cand->fn = fn;
cand->convs = convs;
cand->access_path = access_path;
cand->conversion_path = conversion_path;
cand->viable = viable;
cand->next = *candidates;
*candidates = cand;
return cand;
}
/* Create an overload candidate for the function or method FN called with
the argument list ARGLIST and add it to CANDIDATES. FLAGS is passed on
to implicit_conversion.
CTYPE, if non-NULL, is the type we want to pretend this function
comes from for purposes of overload resolution. */
static struct z_candidate *
add_function_candidate (struct z_candidate **candidates,
tree fn, tree ctype, tree arglist,
tree access_path, tree conversion_path,
int flags)
{
tree parmlist = TYPE_ARG_TYPES (TREE_TYPE (fn));
int i, len;
tree convs;
tree parmnode, argnode;
int viable = 1;
/* Built-in functions that haven't been declared don't really
exist. */
if (DECL_ANTICIPATED (fn))
return NULL;
/* The `this', `in_chrg' and VTT arguments to constructors are not
considered in overload resolution. */
if (DECL_CONSTRUCTOR_P (fn))
{
parmlist = skip_artificial_parms_for (fn, parmlist);
arglist = skip_artificial_parms_for (fn, arglist);
}
len = list_length (arglist);
convs = make_tree_vec (len);
/* 13.3.2 - Viable functions [over.match.viable]
First, to be a viable function, a candidate function shall have enough
parameters to agree in number with the arguments in the list.
We need to check this first; otherwise, checking the ICSes might cause
us to produce an ill-formed template instantiation. */
parmnode = parmlist;
for (i = 0; i < len; ++i)
{
if (parmnode == NULL_TREE || parmnode == void_list_node)
break;
parmnode = TREE_CHAIN (parmnode);
}
if (i < len && parmnode)
viable = 0;
/* Make sure there are default args for the rest of the parms. */
else if (!sufficient_parms_p (parmnode))
viable = 0;
if (! viable)
goto out;
/* Second, for F to be a viable function, there shall exist for each
argument an implicit conversion sequence that converts that argument
to the corresponding parameter of F. */
parmnode = parmlist;
argnode = arglist;
for (i = 0; i < len; ++i)
{
tree arg = TREE_VALUE (argnode);
tree argtype = lvalue_type (arg);
tree t;
int is_this;
if (parmnode == void_list_node)
break;
is_this = (i == 0 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
&& ! DECL_CONSTRUCTOR_P (fn));
if (parmnode)
{
tree parmtype = TREE_VALUE (parmnode);
/* The type of the implicit object parameter ('this') for
overload resolution is not always the same as for the
function itself; conversion functions are considered to
be members of the class being converted, and functions
introduced by a using-declaration are considered to be
members of the class that uses them.
Since build_over_call ignores the ICS for the `this'
parameter, we can just change the parm type. */
if (ctype && is_this)
{
parmtype
= build_qualified_type (ctype,
TYPE_QUALS (TREE_TYPE (parmtype)));
parmtype = build_pointer_type (parmtype);
}
t = implicit_conversion (parmtype, argtype, arg, flags);
}
else
{
t = build1 (IDENTITY_CONV, argtype, arg);
ICS_ELLIPSIS_FLAG (t) = 1;
}
if (t && is_this)
ICS_THIS_FLAG (t) = 1;
TREE_VEC_ELT (convs, i) = t;
if (! t)
{
viable = 0;
break;
}
if (ICS_BAD_FLAG (t))
viable = -1;
if (parmnode)
parmnode = TREE_CHAIN (parmnode);
argnode = TREE_CHAIN (argnode);
}
out:
return add_candidate (candidates, fn, convs, access_path,
conversion_path, viable);
}
/* Create an overload candidate for the conversion function FN which will
be invoked for expression OBJ, producing a pointer-to-function which
will in turn be called with the argument list ARGLIST, and add it to
CANDIDATES. FLAGS is passed on to implicit_conversion.
Actually, we don't really care about FN; we care about the type it
converts to. There may be multiple conversion functions that will
convert to that type, and we rely on build_user_type_conversion_1 to
choose the best one; so when we create our candidate, we record the type
instead of the function. */
static struct z_candidate *
add_conv_candidate (candidates, fn, obj, arglist, access_path,
conversion_path)
struct z_candidate **candidates;
tree fn, obj, arglist;
tree access_path;
tree conversion_path;
{
tree totype = TREE_TYPE (TREE_TYPE (fn));
int i, len, viable, flags;
tree parmlist, convs, parmnode, argnode;
for (parmlist = totype; TREE_CODE (parmlist) != FUNCTION_TYPE; )
parmlist = TREE_TYPE (parmlist);
parmlist = TYPE_ARG_TYPES (parmlist);
len = list_length (arglist) + 1;
convs = make_tree_vec (len);
parmnode = parmlist;
argnode = arglist;
viable = 1;
flags = LOOKUP_NORMAL;
/* Don't bother looking up the same type twice. */
if (*candidates && (*candidates)->fn == totype)
return NULL;
for (i = 0; i < len; ++i)
{
tree arg = i == 0 ? obj : TREE_VALUE (argnode);
tree argtype = lvalue_type (arg);
tree t;
if (i == 0)
t = implicit_conversion (totype, argtype, arg, flags);
else if (parmnode == void_list_node)
break;
else if (parmnode)
t = implicit_conversion (TREE_VALUE (parmnode), argtype, arg, flags);
else
{
t = build1 (IDENTITY_CONV, argtype, arg);
ICS_ELLIPSIS_FLAG (t) = 1;
}
TREE_VEC_ELT (convs, i) = t;
if (! t)
break;
if (ICS_BAD_FLAG (t))
viable = -1;
if (i == 0)
continue;
if (parmnode)
parmnode = TREE_CHAIN (parmnode);
argnode = TREE_CHAIN (argnode);
}
if (i < len)
viable = 0;
if (!sufficient_parms_p (parmnode))
viable = 0;
return add_candidate (candidates, totype, convs, access_path,
conversion_path, viable);
}
static void
build_builtin_candidate (candidates, fnname, type1, type2,
args, argtypes, flags)
struct z_candidate **candidates;
tree fnname, type1, type2, *args, *argtypes;
int flags;
{
tree t, convs;
int viable = 1, i;
tree types[2];
types[0] = type1;
types[1] = type2;
convs = make_tree_vec (args[2] ? 3 : (args[1] ? 2 : 1));
for (i = 0; i < 2; ++i)
{
if (! args[i])
break;
t = implicit_conversion (types[i], argtypes[i], args[i], flags);
if (! t)
{
viable = 0;
/* We need something for printing the candidate. */
t = build1 (IDENTITY_CONV, types[i], NULL_TREE);
}
else if (ICS_BAD_FLAG (t))
viable = 0;
TREE_VEC_ELT (convs, i) = t;
}
/* For COND_EXPR we rearranged the arguments; undo that now. */
if (args[2])
{
TREE_VEC_ELT (convs, 2) = TREE_VEC_ELT (convs, 1);
TREE_VEC_ELT (convs, 1) = TREE_VEC_ELT (convs, 0);
t = implicit_conversion (boolean_type_node, argtypes[2], args[2], flags);
if (t)
TREE_VEC_ELT (convs, 0) = t;
else
viable = 0;
}
add_candidate (candidates, fnname, convs,
/*access_path=*/NULL_TREE,
/*conversion_path=*/NULL_TREE,
viable);
}
static int
is_complete (t)
tree t;
{
return COMPLETE_TYPE_P (complete_type (t));
}
/* Returns nonzero if TYPE is a promoted arithmetic type. */
static int
promoted_arithmetic_type_p (type)
tree type;
{
/* [over.built]
In this section, the term promoted integral type is used to refer
to those integral types which are preserved by integral promotion
(including e.g. int and long but excluding e.g. char).
Similarly, the term promoted arithmetic type refers to promoted
integral types plus floating types. */
return ((INTEGRAL_TYPE_P (type)
&& same_type_p (type_promotes_to (type), type))
|| TREE_CODE (type) == REAL_TYPE);
}
/* Create any builtin operator overload candidates for the operator in
question given the converted operand types TYPE1 and TYPE2. The other
args are passed through from add_builtin_candidates to
build_builtin_candidate.
TYPE1 and TYPE2 may not be permissible, and we must filter them.
If CODE is requires candidates operands of the same type of the kind
of which TYPE1 and TYPE2 are, we add both candidates
CODE (TYPE1, TYPE1) and CODE (TYPE2, TYPE2). */
static void
add_builtin_candidate (candidates, code, code2, fnname, type1, type2,
args, argtypes, flags)
struct z_candidate **candidates;
enum tree_code code, code2;
tree fnname, type1, type2, *args, *argtypes;
int flags;
{
switch (code)
{
case POSTINCREMENT_EXPR:
case POSTDECREMENT_EXPR:
args[1] = integer_zero_node;
type2 = integer_type_node;
break;
default:
break;
}
switch (code)
{
/* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
and VQ is either volatile or empty, there exist candidate operator
functions of the form
VQ T& operator++(VQ T&);
T operator++(VQ T&, int);
5 For every pair T, VQ), where T is an enumeration type or an arithmetic
type other than bool, and VQ is either volatile or empty, there exist
candidate operator functions of the form
VQ T& operator--(VQ T&);
T operator--(VQ T&, int);
6 For every pair T, VQ), where T is a cv-qualified or cv-unqualified
complete object type, and VQ is either volatile or empty, there exist
candidate operator functions of the form
T*VQ& operator++(T*VQ&);
T*VQ& operator--(T*VQ&);
T* operator++(T*VQ&, int);
T* operator--(T*VQ&, int); */
case POSTDECREMENT_EXPR:
case PREDECREMENT_EXPR:
if (TREE_CODE (type1) == BOOLEAN_TYPE)
return;
case POSTINCREMENT_EXPR:
case PREINCREMENT_EXPR:
if (ARITHMETIC_TYPE_P (type1) || TYPE_PTROB_P (type1))
{
type1 = build_reference_type (type1);
break;
}
return;
/* 7 For every cv-qualified or cv-unqualified complete object type T, there
exist candidate operator functions of the form
T& operator*(T*);
8 For every function type T, there exist candidate operator functions of
the form
T& operator*(T*); */
case INDIRECT_REF:
if (TREE_CODE (type1) == POINTER_TYPE
&& (TYPE_PTROB_P (type1)
|| TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE))
break;
return;
/* 9 For every type T, there exist candidate operator functions of the form
T* operator+(T*);
10For every promoted arithmetic type T, there exist candidate operator
functions of the form
T operator+(T);
T operator-(T); */
case CONVERT_EXPR: /* unary + */
if (TREE_CODE (type1) == POINTER_TYPE
&& TREE_CODE (TREE_TYPE (type1)) != OFFSET_TYPE)
break;
case NEGATE_EXPR:
if (ARITHMETIC_TYPE_P (type1))
break;
return;
/* 11For every promoted integral type T, there exist candidate operator
functions of the form
T operator~(T); */
case BIT_NOT_EXPR:
if (INTEGRAL_TYPE_P (type1))
break;
return;
/* 12For every quintuple C1, C2, T, CV1, CV2), where C2 is a class type, C1
is the same type as C2 or is a derived class of C2, T is a complete
object type or a function type, and CV1 and CV2 are cv-qualifier-seqs,
there exist candidate operator functions of the form
CV12 T& operator->*(CV1 C1*, CV2 T C2::*);
where CV12 is the union of CV1 and CV2. */
case MEMBER_REF:
if (TREE_CODE (type1) == POINTER_TYPE
&& (TYPE_PTRMEMFUNC_P (type2) || TYPE_PTRMEM_P (type2)))
{
tree c1 = TREE_TYPE (type1);
tree c2 = (TYPE_PTRMEMFUNC_P (type2)
? TYPE_METHOD_BASETYPE (TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (type2)))
: TYPE_OFFSET_BASETYPE (TREE_TYPE (type2)));
if (IS_AGGR_TYPE (c1) && DERIVED_FROM_P (c2, c1)
&& (TYPE_PTRMEMFUNC_P (type2)
|| is_complete (TREE_TYPE (TREE_TYPE (type2)))))
break;
}
return;
/* 13For every pair of promoted arithmetic types L and R, there exist can-
didate operator functions of the form
LR operator*(L, R);
LR operator/(L, R);
LR operator+(L, R);
LR operator-(L, R);
bool operator<(L, R);
bool operator>(L, R);
bool operator<=(L, R);
bool operator>=(L, R);
bool operator==(L, R);
bool operator!=(L, R);
where LR is the result of the usual arithmetic conversions between
types L and R.
14For every pair of types T and I, where T is a cv-qualified or cv-
unqualified complete object type and I is a promoted integral type,
there exist candidate operator functions of the form
T* operator+(T*, I);
T& operator[](T*, I);
T* operator-(T*, I);
T* operator+(I, T*);
T& operator[](I, T*);
15For every T, where T is a pointer to complete object type, there exist
candidate operator functions of the form112)
ptrdiff_t operator-(T, T);
16For every pointer or enumeration type T, there exist candidate operator
functions of the form
bool operator<(T, T);
bool operator>(T, T);
bool operator<=(T, T);
bool operator>=(T, T);
bool operator==(T, T);
bool operator!=(T, T);
17For every pointer to member type T, there exist candidate operator
functions of the form
bool operator==(T, T);
bool operator!=(T, T); */
case MINUS_EXPR:
if (TYPE_PTROB_P (type1) && TYPE_PTROB_P (type2))
break;
if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
{
type2 = ptrdiff_type_node;
break;
}
case MULT_EXPR:
case TRUNC_DIV_EXPR:
if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
break;
return;
case EQ_EXPR:
case NE_EXPR:
if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
|| (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2)))
break;
if ((TYPE_PTRMEMFUNC_P (type1) || TYPE_PTRMEM_P (type1))
&& null_ptr_cst_p (args[1]))
{
type2 = type1;
break;
}
if ((TYPE_PTRMEMFUNC_P (type2) || TYPE_PTRMEM_P (type2))
&& null_ptr_cst_p (args[0]))
{
type1 = type2;
break;
}
/* FALLTHROUGH */
case LT_EXPR:
case GT_EXPR:
case LE_EXPR:
case GE_EXPR:
case MAX_EXPR:
case MIN_EXPR:
if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
break;
if (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
break;
if (TREE_CODE (type1) == ENUMERAL_TYPE && TREE_CODE (type2) == ENUMERAL_TYPE)
break;
if (TYPE_PTR_P (type1) && null_ptr_cst_p (args[1]))
{
type2 = type1;
break;
}
if (null_ptr_cst_p (args[0]) && TYPE_PTR_P (type2))
{
type1 = type2;
break;
}
return;
case PLUS_EXPR:
if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
break;
case ARRAY_REF:
if (INTEGRAL_TYPE_P (type1) && TYPE_PTROB_P (type2))
{
type1 = ptrdiff_type_node;
break;
}
if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
{
type2 = ptrdiff_type_node;
break;
}
return;
/* 18For every pair of promoted integral types L and R, there exist candi-
date operator functions of the form
LR operator%(L, R);
LR operator&(L, R);
LR operator^(L, R);
LR operator|(L, R);
L operator<<(L, R);
L operator>>(L, R);
where LR is the result of the usual arithmetic conversions between
types L and R. */
case TRUNC_MOD_EXPR:
case BIT_AND_EXPR:
case BIT_IOR_EXPR:
case BIT_XOR_EXPR:
case LSHIFT_EXPR:
case RSHIFT_EXPR:
if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
break;
return;
/* 19For every triple L, VQ, R), where L is an arithmetic or enumeration
type, VQ is either volatile or empty, and R is a promoted arithmetic
type, there exist candidate operator functions of the form
VQ L& operator=(VQ L&, R);
VQ L& operator*=(VQ L&, R);
VQ L& operator/=(VQ L&, R);
VQ L& operator+=(VQ L&, R);
VQ L& operator-=(VQ L&, R);
20For every pair T, VQ), where T is any type and VQ is either volatile
or empty, there exist candidate operator functions of the form
T*VQ& operator=(T*VQ&, T*);
21For every pair T, VQ), where T is a pointer to member type and VQ is
either volatile or empty, there exist candidate operator functions of
the form
VQ T& operator=(VQ T&, T);
22For every triple T, VQ, I), where T is a cv-qualified or cv-
unqualified complete object type, VQ is either volatile or empty, and
I is a promoted integral type, there exist candidate operator func-
tions of the form
T*VQ& operator+=(T*VQ&, I);
T*VQ& operator-=(T*VQ&, I);
23For every triple L, VQ, R), where L is an integral or enumeration
type, VQ is either volatile or empty, and R is a promoted integral
type, there exist candidate operator functions of the form
VQ L& operator%=(VQ L&, R);
VQ L& operator<<=(VQ L&, R);
VQ L& operator>>=(VQ L&, R);
VQ L& operator&=(VQ L&, R);
VQ L& operator^=(VQ L&, R);
VQ L& operator|=(VQ L&, R); */
case MODIFY_EXPR:
switch (code2)
{
case PLUS_EXPR:
case MINUS_EXPR:
if (TYPE_PTROB_P (type1) && INTEGRAL_TYPE_P (type2))
{
type2 = ptrdiff_type_node;
break;
}
case MULT_EXPR:
case TRUNC_DIV_EXPR:
if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
break;
return;
case TRUNC_MOD_EXPR:
case BIT_AND_EXPR:
case BIT_IOR_EXPR:
case BIT_XOR_EXPR:
case LSHIFT_EXPR:
case RSHIFT_EXPR:
if (INTEGRAL_TYPE_P (type1) && INTEGRAL_TYPE_P (type2))
break;
return;
case NOP_EXPR:
if (ARITHMETIC_TYPE_P (type1) && ARITHMETIC_TYPE_P (type2))
break;
if ((TYPE_PTRMEMFUNC_P (type1) && TYPE_PTRMEMFUNC_P (type2))
|| (TYPE_PTR_P (type1) && TYPE_PTR_P (type2))
|| (TYPE_PTRMEM_P (type1) && TYPE_PTRMEM_P (type2))
|| ((TYPE_PTRMEMFUNC_P (type1)
|| TREE_CODE (type1) == POINTER_TYPE)
&& null_ptr_cst_p (args[1])))
{
type2 = type1;
break;
}
return;
default:
abort ();
}
type1 = build_reference_type (type1);
break;
case COND_EXPR:
/* [over.built]
For every pair of promoted arithmetic types L and R, there
exist candidate operator functions of the form
LR operator?(bool, L, R);
where LR is the result of the usual arithmetic conversions
between types L and R.
For every type T, where T is a pointer or pointer-to-member
type, there exist candidate operator functions of the form T
operator?(bool, T, T); */
if (promoted_arithmetic_type_p (type1)
&& promoted_arithmetic_type_p (type2))
/* That's OK. */
break;
/* Otherwise, the types should be pointers. */
if (!(TREE_CODE (type1) == POINTER_TYPE
|| TYPE_PTRMEM_P (type1)
|| TYPE_PTRMEMFUNC_P (type1))
|| !(TREE_CODE (type2) == POINTER_TYPE
|| TYPE_PTRMEM_P (type2)
|| TYPE_PTRMEMFUNC_P (type2)))
return;
/* We don't check that the two types are the same; the logic
below will actually create two candidates; one in which both
parameter types are TYPE1, and one in which both parameter
types are TYPE2. */
break;
default:
abort ();
}
/* If we're dealing with two pointer types or two enumeral types,
we need candidates for both of them. */
if (type2 && !same_type_p (type1, type2)
&& TREE_CODE (type1) == TREE_CODE (type2)
&& (TREE_CODE (type1) == REFERENCE_TYPE
|| (TREE_CODE (type1) == POINTER_TYPE
&& TYPE_PTRMEM_P (type1) == TYPE_PTRMEM_P (type2))
|| TYPE_PTRMEMFUNC_P (type1)
|| IS_AGGR_TYPE (type1)
|| TREE_CODE (type1) == ENUMERAL_TYPE))
{
build_builtin_candidate
(candidates, fnname, type1, type1, args, argtypes, flags);
build_builtin_candidate
(candidates, fnname, type2, type2, args, argtypes, flags);
return;
}
build_builtin_candidate
(candidates, fnname, type1, type2, args, argtypes, flags);
}
tree
type_decays_to (type)
tree type;
{
if (TREE_CODE (type) == ARRAY_TYPE)
return build_pointer_type (TREE_TYPE (type));
if (TREE_CODE (type) == FUNCTION_TYPE)
return build_pointer_type (type);
return type;
}
/* There are three conditions of builtin candidates:
1) bool-taking candidates. These are the same regardless of the input.
2) pointer-pair taking candidates. These are generated for each type
one of the input types converts to.
3) arithmetic candidates. According to the standard, we should generate
all of these, but I'm trying not to...
Here we generate a superset of the possible candidates for this particular
case. That is a subset of the full set the standard defines, plus some
other cases which the standard disallows. add_builtin_candidate will
filter out the invalid set. */
static void
add_builtin_candidates (candidates, code, code2, fnname, args, flags)
struct z_candidate **candidates;
enum tree_code code, code2;
tree fnname, *args;
int flags;
{
int ref1, i;
int enum_p = 0;
tree type, argtypes[3];
/* TYPES[i] is the set of possible builtin-operator parameter types
we will consider for the Ith argument. These are represented as
a TREE_LIST; the TREE_VALUE of each node is the potential
parameter type. */
tree types[2];
for (i = 0; i < 3; ++i)
{
if (args[i])
argtypes[i] = lvalue_type (args[i]);
else
argtypes[i] = NULL_TREE;
}
switch (code)
{
/* 4 For every pair T, VQ), where T is an arithmetic or enumeration type,
and VQ is either volatile or empty, there exist candidate operator
functions of the form
VQ T& operator++(VQ T&); */
case POSTINCREMENT_EXPR:
case PREINCREMENT_EXPR:
case POSTDECREMENT_EXPR:
case PREDECREMENT_EXPR:
case MODIFY_EXPR:
ref1 = 1;
break;
/* 24There also exist candidate operator functions of the form
bool operator!(bool);
bool operator&&(bool, bool);
bool operator||(bool, bool); */
case TRUTH_NOT_EXPR:
build_builtin_candidate
(candidates, fnname, boolean_type_node,
NULL_TREE, args, argtypes, flags);
return;
case TRUTH_ORIF_EXPR:
case TRUTH_ANDIF_EXPR:
build_builtin_candidate
(candidates, fnname, boolean_type_node,
boolean_type_node, args, argtypes, flags);
return;
case ADDR_EXPR:
case COMPOUND_EXPR:
case COMPONENT_REF:
return;
case COND_EXPR:
case EQ_EXPR:
case NE_EXPR:
case LT_EXPR:
case LE_EXPR:
case GT_EXPR:
case GE_EXPR:
enum_p = 1;
/* FALLTHROUGH */
default:
ref1 = 0;
}
types[0] = types[1] = NULL_TREE;
for (i = 0; i < 2; ++i)
{
if (! args[i])
;
else if (IS_AGGR_TYPE (argtypes[i]))
{
tree convs;
if (i == 0 && code == MODIFY_EXPR && code2 == NOP_EXPR)
return;
convs = lookup_conversions (argtypes[i]);
if (code == COND_EXPR)
{
if (real_lvalue_p (args[i]))
types[i] = tree_cons
(NULL_TREE, build_reference_type (argtypes[i]), types[i]);
types[i] = tree_cons
(NULL_TREE, TYPE_MAIN_VARIANT (argtypes[i]), types[i]);
}
else if (! convs)
return;
for (; convs; convs = TREE_CHAIN (convs))
{
type = TREE_TYPE (TREE_TYPE (OVL_CURRENT (TREE_VALUE (convs))));
if (i == 0 && ref1
&& (TREE_CODE (type) != REFERENCE_TYPE
|| CP_TYPE_CONST_P (TREE_TYPE (type))))
continue;
if (code == COND_EXPR && TREE_CODE (type) == REFERENCE_TYPE)
types[i] = tree_cons (NULL_TREE, type, types[i]);
type = non_reference (type);
if (i != 0 || ! ref1)
{
type = TYPE_MAIN_VARIANT (type_decays_to (type));
if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
types[i] = tree_cons (NULL_TREE, type, types[i]);
if (INTEGRAL_TYPE_P (type))
type = type_promotes_to (type);
}
if (! value_member (type, types[i]))
types[i] = tree_cons (NULL_TREE, type, types[i]);
}
}
else
{
if (code == COND_EXPR && real_lvalue_p (args[i]))
types[i] = tree_cons
(NULL_TREE, build_reference_type (argtypes[i]), types[i]);
type = non_reference (argtypes[i]);
if (i != 0 || ! ref1)
{
type = TYPE_MAIN_VARIANT (type_decays_to (type));
if (enum_p && TREE_CODE (type) == ENUMERAL_TYPE)
types[i] = tree_cons (NULL_TREE, type, types[i]);
if (INTEGRAL_TYPE_P (type))
type = type_promotes_to (type);
}
types[i] = tree_cons (NULL_TREE, type, types[i]);
}
}
/* Run through the possible parameter types of both arguments,
creating candidates with those parameter types. */
for (; types[0]; types[0] = TREE_CHAIN (types[0]))
{
if (types[1])
for (type = types[1]; type; type = TREE_CHAIN (type))
add_builtin_candidate
(candidates, code, code2, fnname, TREE_VALUE (types[0]),
TREE_VALUE (type), args, argtypes, flags);
else
add_builtin_candidate
(candidates, code, code2, fnname, TREE_VALUE (types[0]),
NULL_TREE, args, argtypes, flags);
}
return;
}
/* If TMPL can be successfully instantiated as indicated by
EXPLICIT_TARGS and ARGLIST, adds the instantiation to CANDIDATES.
TMPL is the template. EXPLICIT_TARGS are any explicit template
arguments. ARGLIST is the arguments provided at the call-site.
The RETURN_TYPE is the desired type for conversion operators. If
OBJ is NULL_TREE, FLAGS and CTYPE are as for add_function_candidate.
If an OBJ is supplied, FLAGS and CTYPE are ignored, and OBJ is as for
add_conv_candidate. */
static struct z_candidate*
add_template_candidate_real (candidates, tmpl, ctype, explicit_targs,
arglist, return_type, access_path,
conversion_path, flags, obj, strict)
struct z_candidate **candidates;
tree tmpl, ctype, explicit_targs, arglist, return_type;
tree access_path;
tree conversion_path;
int flags;
tree obj;
unification_kind_t strict;
{
int ntparms = DECL_NTPARMS (tmpl);
tree targs = make_tree_vec (ntparms);
tree args_without_in_chrg = arglist;
struct z_candidate *cand;
int i;
tree fn;
/* We don't do deduction on the in-charge parameter, the VTT
parameter or 'this'. */
if (DECL_NONSTATIC_MEMBER_FUNCTION_P (tmpl))
args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
if ((DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (tmpl)
|| DECL_BASE_CONSTRUCTOR_P (tmpl))
&& TYPE_USES_VIRTUAL_BASECLASSES (DECL_CONTEXT (tmpl)))
args_without_in_chrg = TREE_CHAIN (args_without_in_chrg);
i = fn_type_unification (tmpl, explicit_targs, targs,
args_without_in_chrg,
return_type, strict, -1);
if (i != 0)
return NULL;
fn = instantiate_template (tmpl, targs);
if (fn == error_mark_node)
return NULL;
/* In [class.copy]:
A member function template is never instantiated to perform the
copy of a class object to an object of its class type.
It's a little unclear what this means; the standard explicitly
does allow a template to be used to copy a class. For example,
in:
struct A {
A(A&);
template <class T> A(const T&);
};
const A f ();
void g () { A a (f ()); }
the member template will be used to make the copy. The section
quoted above appears in the paragraph that forbids constructors
whose only parameter is (a possibly cv-qualified variant of) the
class type, and a logical interpretation is that the intent was
to forbid the instantiation of member templates which would then
have that form. */
if (DECL_CONSTRUCTOR_P (fn) && list_length (arglist) == 2)
{
tree arg_types = FUNCTION_FIRST_USER_PARMTYPE (fn);
if (arg_types && same_type_p (TYPE_MAIN_VARIANT (TREE_VALUE (arg_types)),
ctype))
return NULL;
}
if (obj != NULL_TREE)
/* Aha, this is a conversion function. */
cand = add_conv_candidate (candidates, fn, obj, access_path,
conversion_path, arglist);
else
cand = add_function_candidate (candidates, fn, ctype,
arglist, access_path,
conversion_path, flags);
if (DECL_TI_TEMPLATE (fn) != tmpl)
/* This situation can occur if a member template of a template
class is specialized. Then, instantiate_template might return
an instantiation of the specialization, in which case the
DECL_TI_TEMPLATE field will point at the original
specialization. For example:
template <class T> struct S { template <class U> void f(U);
template <> void f(int) {}; };
S<double> sd;
sd.f(3);
Here, TMPL will be template <class U> S<double>::f(U).
And, instantiate template will give us the specialization
template <> S<double>::f(int). But, the DECL_TI_TEMPLATE field
for this will point at template <class T> template <> S<T>::f(int),
so that we can find the definition. For the purposes of
overload resolution, however, we want the original TMPL. */
cand->template = tree_cons (tmpl, targs, NULL_TREE);
else
cand->template = DECL_TEMPLATE_INFO (fn);
return cand;
}
static struct z_candidate *
add_template_candidate (candidates, tmpl, ctype, explicit_targs,
arglist, return_type, access_path,
conversion_path, flags, strict)
struct z_candidate **candidates;
tree tmpl, ctype, explicit_targs, arglist, return_type;
tree access_path;
tree conversion_path;
int flags;
unification_kind_t strict;
{
return
add_template_candidate_real (candidates, tmpl, ctype,
explicit_targs, arglist, return_type,
access_path, conversion_path,
flags, NULL_TREE, strict);
}
static struct z_candidate *
add_template_conv_candidate (candidates, tmpl, obj, arglist, return_type,
access_path, conversion_path)
struct z_candidate **candidates;
tree tmpl, obj, arglist, return_type;
tree access_path;
tree conversion_path;
{
return
add_template_candidate_real (candidates, tmpl, NULL_TREE, NULL_TREE,
arglist, return_type, access_path,
conversion_path, 0, obj, DEDUCE_CONV);
}
static int
any_viable (cands)
struct z_candidate *cands;
{
for (; cands; cands = cands->next)
if (pedantic ? cands->viable == 1 : cands->viable)
return 1;
return 0;
}
static int
any_strictly_viable (cands)
struct z_candidate *cands;
{
for (; cands; cands = cands->next)
if (cands->viable == 1)
return 1;
return 0;
}
static struct z_candidate *
splice_viable (cands)
struct z_candidate *cands;
{
struct z_candidate **p = &cands;
for (; *p; )
{
if (pedantic ? (*p)->viable == 1 : (*p)->viable)
p = &((*p)->next);
else
*p = (*p)->next;
}
return cands;
}
static tree
build_this (obj)
tree obj;
{
/* Fix this to work on non-lvalues. */
return build_unary_op (ADDR_EXPR, obj, 0);
}
/* Returns true iff functions are equivalent. Equivalent functions are
not '==' only if one is a function-local extern function or if
both are extern "C". */
static inline int
equal_functions (fn1, fn2)
tree fn1;
tree fn2;
{
if (DECL_LOCAL_FUNCTION_P (fn1) || DECL_LOCAL_FUNCTION_P (fn2)
|| DECL_EXTERN_C_FUNCTION_P (fn1))
return decls_match (fn1, fn2);
return fn1 == fn2;
}
static void
print_z_candidates (struct z_candidate *candidates)
{
const char *str;
struct z_candidate *cand1;
struct z_candidate **cand2;
/* There may be duplicates in the set of candidates. We put off
checking this condition as long as possible, since we have no way
to eliminate duplicates from a set of functions in less than n^2
time. Now we are about to emit an error message, so it is more
permissible to go slowly. */
for (cand1 = candidates; cand1; cand1 = cand1->next)
{
tree fn = cand1->fn;
/* Skip builtin candidates and conversion functions. */
if (TREE_CODE (fn) != FUNCTION_DECL)
continue;
cand2 = &cand1->next;
while (*cand2)
{
if (TREE_CODE ((*cand2)->fn) == FUNCTION_DECL
&& equal_functions (fn, (*cand2)->fn))
*cand2 = (*cand2)->next;
else
cand2 = &(*cand2)->next;
}
}
str = "candidates are:";
for (; candidates; candidates = candidates->next)
{
if (TREE_CODE (candidates->fn) == IDENTIFIER_NODE)
{
if (TREE_VEC_LENGTH (candidates->convs) == 3)
error ("%s %D(%T, %T, %T) <built-in>", str, candidates->fn,
TREE_TYPE (TREE_VEC_ELT (candidates->convs, 0)),
TREE_TYPE (TREE_VEC_ELT (candidates->convs, 1)),
TREE_TYPE (TREE_VEC_ELT (candidates->convs, 2)));
else if (TREE_VEC_LENGTH (candidates->convs) == 2)
error ("%s %D(%T, %T) <built-in>", str, candidates->fn,
TREE_TYPE (TREE_VEC_ELT (candidates->convs, 0)),
TREE_TYPE (TREE_VEC_ELT (candidates->convs, 1)));
else
error ("%s %D(%T) <built-in>", str, candidates->fn,
TREE_TYPE (TREE_VEC_ELT (candidates->convs, 0)));
}
else if (TYPE_P (candidates->fn))
error ("%s %T <conversion>", str, candidates->fn);
else
cp_error_at ("%s %+#D%s", str, candidates->fn,
candidates->viable == -1 ? " <near match>" : "");
str = " ";
}
}
/* USER_SEQ is a user-defined conversion sequence, beginning with a
USER_CONV. STD_SEQ is the standard conversion sequence applied to
the result of the conversion function to convert it to the final
desired type. Merge the the two sequences into a single sequence,
and return the merged sequence. */
static tree
merge_conversion_sequences (tree user_seq, tree std_seq)
{
tree *t;
my_friendly_assert (TREE_CODE (user_seq) == USER_CONV,
20030306);
/* Find the end of the second conversion sequence. */
t = &(std_seq);
while (TREE_CODE (*t) != IDENTITY_CONV)
t = &TREE_OPERAND (*t, 0);
/* Replace the identity conversion with the user conversion
sequence. */
*t = user_seq;
/* The entire sequence is a user-conversion sequence. */
ICS_USER_FLAG (std_seq) = 1;
return std_seq;
}
/* Returns the best overload candidate to perform the requested
conversion. This function is used for three the overloading situations
described in [over.match.copy], [over.match.conv], and [over.match.ref].
If TOTYPE is a REFERENCE_TYPE, we're trying to find an lvalue binding as
per [dcl.init.ref], so we ignore temporary bindings. */
static struct z_candidate *
build_user_type_conversion_1 (totype, expr, flags)
tree totype, expr;
int flags;
{
struct z_candidate *candidates, *cand;
tree fromtype = TREE_TYPE (expr);
tree ctors = NULL_TREE, convs = NULL_TREE;
tree args = NULL_TREE;
/* We represent conversion within a hierarchy using RVALUE_CONV and
BASE_CONV, as specified by [over.best.ics]; these become plain
constructor calls, as specified in [dcl.init]. */
my_friendly_assert (!IS_AGGR_TYPE (fromtype) || !IS_AGGR_TYPE (totype)
|| !DERIVED_FROM_P (totype, fromtype), 20011226);
if (IS_AGGR_TYPE (totype))
ctors = lookup_fnfields (TYPE_BINFO (totype),
complete_ctor_identifier,
0);
if (IS_AGGR_TYPE (fromtype))
convs = lookup_conversions (fromtype);
candidates = 0;
flags |= LOOKUP_NO_CONVERSION;
if (ctors)
{
tree t;
ctors = BASELINK_FUNCTIONS (ctors);
t = build_int_2 (0, 0);
TREE_TYPE (t) = build_pointer_type (totype);
args = build_tree_list (NULL_TREE, expr);
/* We should never try to call the abstract or base constructor
from here. */
my_friendly_assert (!DECL_HAS_IN_CHARGE_PARM_P (OVL_CURRENT (ctors))
&& !DECL_HAS_VTT_PARM_P (OVL_CURRENT (ctors)),
20011226);
args = tree_cons (NULL_TREE, t, args);
}
for (; ctors; ctors = OVL_NEXT (ctors))
{
tree ctor = OVL_CURRENT (ctors);
if (DECL_NONCONVERTING_P (ctor))
continue;
if (TREE_CODE (ctor) == TEMPLATE_DECL)
cand = add_template_candidate (&candidates, ctor, totype,
NULL_TREE, args, NULL_TREE,
TYPE_BINFO (totype),
TYPE_BINFO (totype),
flags,
DEDUCE_CALL);
else
cand = add_function_candidate (&candidates, ctor, totype,
args, TYPE_BINFO (totype),
TYPE_BINFO (totype),
flags);
if (cand)
cand->second_conv = build1 (IDENTITY_CONV, totype, NULL_TREE);
}
if (convs)
args = build_tree_list (NULL_TREE, build_this (expr));
for (; convs; convs = TREE_CHAIN (convs))
{
tree fns;
tree conversion_path = TREE_PURPOSE (convs);
int convflags = LOOKUP_NO_CONVERSION;
/* If we are called to convert to a reference type, we are trying to
find an lvalue binding, so don't even consider temporaries. If
we don't find an lvalue binding, the caller will try again to
look for a temporary binding. */
if (TREE_CODE (totype) == REFERENCE_TYPE)
convflags |= LOOKUP_NO_TEMP_BIND;
for (fns = TREE_VALUE (convs); fns; fns = OVL_NEXT (fns))
{
tree fn = OVL_CURRENT (fns);
/* [over.match.funcs] For conversion functions, the function
is considered to be a member of the class of the implicit
object argument for the purpose of defining the type of
the implicit object parameter.
So we pass fromtype as CTYPE to add_*_candidate. */
if (TREE_CODE (fn) == TEMPLATE_DECL)
cand = add_template_candidate (&candidates, fn, fromtype, NULL_TREE,
args, totype,
TYPE_BINFO (fromtype),
conversion_path,
flags,
DEDUCE_CONV);
else
cand = add_function_candidate (&candidates, fn, fromtype,
args,
TYPE_BINFO (fromtype),
conversion_path,
flags);
if (cand)
{
tree ics = implicit_conversion
(totype, TREE_TYPE (TREE_TYPE (cand->fn)),
0, convflags);
cand->second_conv = ics;
if (ics == NULL_TREE)
cand->viable = 0;
else if (cand->viable == 1 && ICS_BAD_FLAG (ics))
cand->viable = -1;
}
}
}
if (! any_viable (candidates))
return 0;
candidates = splice_viable (candidates);
cand = tourney (candidates);
if (cand == 0)
{
if (flags & LOOKUP_COMPLAIN)
{
error ("conversion from `%T' to `%T' is ambiguous",
fromtype, totype);
print_z_candidates (candidates);
}
cand = candidates; /* any one will do */
cand->second_conv = build1 (AMBIG_CONV, totype, expr);
ICS_USER_FLAG (cand->second_conv) = 1;
if (!any_strictly_viable (candidates))
ICS_BAD_FLAG (cand->second_conv) = 1;
/* If there are viable candidates, don't set ICS_BAD_FLAG; an
ambiguous conversion is no worse than another user-defined
conversion. */
return cand;
}
/* Build the user conversion sequence. */
convs = build_conv
(USER_CONV,
(DECL_CONSTRUCTOR_P (cand->fn)
? totype : non_reference (TREE_TYPE (TREE_TYPE (cand->fn)))),
build1 (IDENTITY_CONV, TREE_TYPE (expr), expr));
TREE_OPERAND (convs, 1) = build_zc_wrapper (cand);
/* Combine it with the second conversion sequence. */
cand->second_conv = merge_conversion_sequences (convs,
cand->second_conv);
if (cand->viable == -1)
ICS_BAD_FLAG (cand->second_conv) = 1;
return cand;
}
tree
build_user_type_conversion (totype, expr, flags)
tree totype, expr;
int flags;
{
struct z_candidate *cand
= build_user_type_conversion_1 (totype, expr, flags);
if (cand)
{
if (TREE_CODE (cand->second_conv) == AMBIG_CONV)
return error_mark_node;
return convert_from_reference (convert_like (cand->second_conv, expr));
}
return NULL_TREE;
}
/* Find the possibly overloaded set of functions corresponding to a
call of the form SCOPE::NAME (...). NAME might be a
TEMPLATE_ID_EXPR, OVERLOAD, _DECL, IDENTIFIER_NODE or LOOKUP_EXPR. */
tree
resolve_scoped_fn_name (tree scope, tree name)
{
tree fn;
tree template_args = NULL_TREE;
bool is_template_id = TREE_CODE (name) == TEMPLATE_ID_EXPR;
if (is_template_id)
{
template_args = TREE_OPERAND (name, 1);
name = TREE_OPERAND (name, 0);
}
if (TREE_CODE (name) == OVERLOAD)
name = DECL_NAME (get_first_fn (name));
else if (TREE_CODE (name) == LOOKUP_EXPR)
name = TREE_OPERAND (name, 0);
if (TREE_CODE (scope) == NAMESPACE_DECL)
fn = lookup_namespace_name (scope, name);
else if (!CLASS_TYPE_P (scope))
{
error ("`%T' is not a class type", scope);
return error_mark_node;
}
else
{
if (!TYPE_BEING_DEFINED (scope)
&& !COMPLETE_TYPE_P (complete_type (scope)))
{
error ("incomplete type '%T' cannot be used to name a scope",
scope);
return error_mark_node;
}
if (BASELINK_P (name))
fn = name;
else
fn = lookup_member (scope, name, /*protect=*/1, /*prefer_type=*/0);
if (fn && current_class_type)
fn = (adjust_result_of_qualified_name_lookup
(fn, scope, current_class_type));
/* It might be the name of a function pointer member. */
if (fn && TREE_CODE (fn) == FIELD_DECL)
fn = resolve_offset_ref (build_offset_ref (scope, fn));
}
if (!fn)
{
error ("'%D' has no member named '%E'", scope, name);
return error_mark_node;
}
if (is_template_id)
{
tree fns = fn;
if (BASELINK_P (fn))
fns = BASELINK_FUNCTIONS (fns);
fns = build_nt (TEMPLATE_ID_EXPR, fns, template_args);
if (BASELINK_P (fn))
BASELINK_FUNCTIONS (fn) = fns;
else
fn = fns;
}
return fn;
}
/* Do any initial processing on the arguments to a function call. */
static tree
resolve_args (args)
tree args;
{
tree t;
for (t = args; t; t = TREE_CHAIN (t))
{
tree arg = TREE_VALUE (t);
if (arg == error_mark_node)
return error_mark_node;
else if (VOID_TYPE_P (TREE_TYPE (arg)))
{
error ("invalid use of void expression");
return error_mark_node;
}
else if (TREE_CODE (arg) == OFFSET_REF)
arg = resolve_offset_ref (arg);
arg = convert_from_reference (arg);
TREE_VALUE (t) = arg;
}
return args;
}
/* Return an expression for a call to FN (a namespace-scope function)
with the ARGS. */
tree
build_new_function_call (fn, args)
tree fn, args;
{
struct z_candidate *candidates = 0, *cand;
tree explicit_targs = NULL_TREE;
int template_only = 0;
/* Check FN and ARGS. */
my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL
|| TREE_CODE (fn) == TEMPLATE_DECL
|| TREE_CODE (fn) == OVERLOAD
|| TREE_CODE (fn) == TEMPLATE_ID_EXPR,
20020712);
my_friendly_assert (!args || TREE_CODE (args) == TREE_LIST,
20020712);
if (TREE_CODE (fn) == TEMPLATE_ID_EXPR)
{
explicit_targs = TREE_OPERAND (fn, 1);
fn = TREE_OPERAND (fn, 0);
template_only = 1;
}
if (really_overloaded_fn (fn)
|| TREE_CODE (fn) == TEMPLATE_DECL)
{
tree t1;
args = resolve_args (args);
if (args == error_mark_node)
return error_mark_node;
for (t1 = fn; t1; t1 = OVL_NEXT (t1))
{
tree t = OVL_CURRENT (t1);
if (TREE_CODE (t) == TEMPLATE_DECL)
add_template_candidate
(&candidates, t, NULL_TREE, explicit_targs, args,
NULL_TREE,
/*access_path=*/NULL_TREE, /*conversion_path=*/NULL_TREE,
LOOKUP_NORMAL, DEDUCE_CALL);
else if (! template_only)
add_function_candidate
(&candidates, t, NULL_TREE, args, /*access_path=*/NULL_TREE,
/*conversion_path=*/NULL_TREE, LOOKUP_NORMAL);
}
if (! any_viable (candidates))
{
if (candidates && ! candidates->next)
return build_function_call (candidates->fn, args);
error ("no matching function for call to `%D(%A)'",
DECL_NAME (OVL_CURRENT (fn)), args);
if (candidates)
print_z_candidates (candidates);
return error_mark_node;
}
candidates = splice_viable (candidates);
cand = tourney (candidates);
if (cand == 0)
{
error ("call of overloaded `%D(%A)' is ambiguous",
DECL_NAME (OVL_FUNCTION (fn)), args);
print_z_candidates (candidates);
return error_mark_node;
}
return build_over_call (cand, args, LOOKUP_NORMAL);
}
/* This is not really overloaded. */
fn = OVL_CURRENT (fn);
return build_function_call (fn, args);
}
static tree
build_object_call (obj, args)
tree obj, args;
{
struct z_candidate *candidates = 0, *cand;
tree fns, convs, mem_args = NULL_TREE;
tree type = TREE_TYPE (obj);
if (TYPE_PTRMEMFUNC_P (type))
{
/* It's no good looking for an overloaded operator() on a
pointer-to-member-function. */
error ("pointer-to-member function %E cannot be called without an object; consider using .* or ->*", obj);
return error_mark_node;
}
fns = lookup_fnfields (TYPE_BINFO (type), ansi_opname (CALL_EXPR), 1);
if (fns == error_mark_node)
return error_mark_node;
args = resolve_args (args);
if (args == error_mark_node)
return error_mark_node;
if (fns)
{
tree base = BINFO_TYPE (BASELINK_BINFO (fns));
mem_args = tree_cons (NULL_TREE, build_this (obj), args);
for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
{
tree fn = OVL_CURRENT (fns);
if (TREE_CODE (fn) == TEMPLATE_DECL)
add_template_candidate (&candidates, fn, base, NULL_TREE,
mem_args, NULL_TREE,
TYPE_BINFO (type),
TYPE_BINFO (type),
LOOKUP_NORMAL, DEDUCE_CALL);
else
add_function_candidate
(&candidates, fn, base, mem_args, TYPE_BINFO (type),
TYPE_BINFO (type), LOOKUP_NORMAL);
}
}
convs = lookup_conversions (type);
for (; convs; convs = TREE_CHAIN (convs))
{
tree fns = TREE_VALUE (convs);
tree totype = TREE_TYPE (TREE_TYPE (OVL_CURRENT (fns)));
if ((TREE_CODE (totype) == POINTER_TYPE
&& TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
|| (TREE_CODE (totype) == REFERENCE_TYPE
&& TREE_CODE (TREE_TYPE (totype)) == FUNCTION_TYPE)
|| (TREE_CODE (totype) == REFERENCE_TYPE
&& TREE_CODE (TREE_TYPE (totype)) == POINTER_TYPE
&& TREE_CODE (TREE_TYPE (TREE_TYPE (totype))) == FUNCTION_TYPE))
for (; fns; fns = OVL_NEXT (fns))
{
tree fn = OVL_CURRENT (fns);
if (TREE_CODE (fn) == TEMPLATE_DECL)
add_template_conv_candidate
(&candidates, fn, obj, args, totype,
/*access_path=*/NULL_TREE,
/*conversion_path=*/NULL_TREE);
else
add_conv_candidate (&candidates, fn, obj, args,
/*conversion_path=*/NULL_TREE,
/*access_path=*/NULL_TREE);
}
}
if (! any_viable (candidates))
{
error ("no match for call to `(%T) (%A)'", TREE_TYPE (obj), args);
print_z_candidates (candidates);
return error_mark_node;
}
candidates = splice_viable (candidates);
cand = tourney (candidates);
if (cand == 0)
{
error ("call of `(%T) (%A)' is ambiguous", TREE_TYPE (obj), args);
print_z_candidates (candidates);
return error_mark_node;
}
/* Since cand->fn will be a type, not a function, for a conversion
function, we must be careful not to unconditionally look at
DECL_NAME here. */
if (TREE_CODE (cand->fn) == FUNCTION_DECL
&& DECL_OVERLOADED_OPERATOR_P (cand->fn) == CALL_EXPR)
return build_over_call (cand, mem_args, LOOKUP_NORMAL);
obj = convert_like_with_context
(TREE_VEC_ELT (cand->convs, 0), obj, cand->fn, -1);
/* FIXME */
return build_function_call (obj, args);
}
static void
op_error (code, code2, arg1, arg2, arg3, problem)
enum tree_code code, code2;
tree arg1, arg2, arg3;
const char *problem;
{
const char *opname;
if (code == MODIFY_EXPR)
opname = assignment_operator_name_info[code2].name;
else
opname = operator_name_info[code].name;
switch (code)
{
case COND_EXPR:
error ("%s for ternary 'operator?:' in '%E ? %E : %E'",
problem, arg1, arg2, arg3);
break;
case POSTINCREMENT_EXPR:
case POSTDECREMENT_EXPR:
error ("%s for 'operator%s' in '%E%s'", problem, opname, arg1, opname);
break;
case ARRAY_REF:
error ("%s for 'operator[]' in '%E[%E]'", problem, arg1, arg2);
break;
default:
if (arg2)
error ("%s for 'operator%s' in '%E %s %E'",
problem, opname, arg1, opname, arg2);
else
error ("%s for 'operator%s' in '%s%E'",
problem, opname, opname, arg1);
break;
}
}
/* Return the implicit conversion sequence that could be used to
convert E1 to E2 in [expr.cond]. */
static tree
conditional_conversion (e1, e2)
tree e1;
tree e2;
{
tree t1 = non_reference (TREE_TYPE (e1));
tree t2 = non_reference (TREE_TYPE (e2));
tree conv;
bool good_base;
/* [expr.cond]
If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
implicitly converted (clause _conv_) to the type "reference to
T2", subject to the constraint that in the conversion the
reference must bind directly (_dcl.init.ref_) to E1. */
if (real_lvalue_p (e2))
{
conv = implicit_conversion (build_reference_type (t2),
t1,
e1,
LOOKUP_NO_TEMP_BIND);
if (conv)
return conv;
}
/* [expr.cond]
If E1 and E2 have class type, and the underlying class types are
the same or one is a base class of the other: E1 can be converted
to match E2 if the class of T2 is the same type as, or a base
class of, the class of T1, and the cv-qualification of T2 is the
same cv-qualification as, or a greater cv-qualification than, the
cv-qualification of T1. If the conversion is applied, E1 is
changed to an rvalue of type T2 that still refers to the original
source class object (or the appropriate subobject thereof). */
if (CLASS_TYPE_P (t1) && CLASS_TYPE_P (t2)
&& ((good_base = DERIVED_FROM_P (t2, t1)) || DERIVED_FROM_P (t1, t2)))
{
if (good_base && at_least_as_qualified_p (t2, t1))
{
conv = build1 (IDENTITY_CONV, t1, e1);
if (!same_type_p (TYPE_MAIN_VARIANT (t1),
TYPE_MAIN_VARIANT (t2)))
conv = build_conv (BASE_CONV, t2, conv);
return conv;
}
else
return NULL_TREE;
}
else
/* [expr.cond]
Otherwise: E1 can be converted to match E2 if E1 can be implicitly
converted to the type that expression E2 would have if E2 were
converted to an rvalue (or the type it has, if E2 is an rvalue). */
return implicit_conversion (t2, t1, e1, LOOKUP_NORMAL);
}
/* Implement [expr.cond]. ARG1, ARG2, and ARG3 are the three
arguments to the conditional expression. */
tree
build_conditional_expr (arg1, arg2, arg3)
tree arg1;
tree arg2;
tree arg3;
{
tree arg2_type;
tree arg3_type;
tree result;
tree result_type = NULL_TREE;
int lvalue_p = 1;
struct z_candidate *candidates = 0;
struct z_candidate *cand;
/* As a G++ extension, the second argument to the conditional can be
omitted. (So that `a ? : c' is roughly equivalent to `a ? a :
c'.) If the second operand is omitted, make sure it is
calculated only once. */
if (!arg2)
{
if (pedantic)
pedwarn ("ISO C++ forbids omitting the middle term of a ?: expression");
arg1 = arg2 = save_expr (arg1);
}
/* [expr.cond]
The first expr ession is implicitly converted to bool (clause
_conv_). */
arg1 = cp_convert (boolean_type_node, arg1);
/* If something has already gone wrong, just pass that fact up the
tree. */
if (arg1 == error_mark_node
|| arg2 == error_mark_node
|| arg3 == error_mark_node
|| TREE_TYPE (arg1) == error_mark_node
|| TREE_TYPE (arg2) == error_mark_node
|| TREE_TYPE (arg3) == error_mark_node)
return error_mark_node;
/* [expr.cond]
If either the second or the third operand has type (possibly
cv-qualified) void, then the lvalue-to-rvalue (_conv.lval_),
array-to-pointer (_conv.array_), and function-to-pointer
(_conv.func_) standard conversions are performed on the second
and third operands. */
arg2_type = TREE_TYPE (arg2);
arg3_type = TREE_TYPE (arg3);
if (VOID_TYPE_P (arg2_type) || VOID_TYPE_P (arg3_type))
{
/* Do the conversions. We don't these for `void' type arguments
since it can't have any effect and since decay_conversion
does not handle that case gracefully. */
if (!VOID_TYPE_P (arg2_type))
arg2 = decay_conversion (arg2);
if (!VOID_TYPE_P (arg3_type))
arg3 = decay_conversion (arg3);
arg2_type = TREE_TYPE (arg2);
arg3_type = TREE_TYPE (arg3);
/* [expr.cond]
One of the following shall hold:
--The second or the third operand (but not both) is a
throw-expression (_except.throw_); the result is of the
type of the other and is an rvalue.
--Both the second and the third operands have type void; the
result is of type void and is an rvalue. */
if ((TREE_CODE (arg2) == THROW_EXPR)
^ (TREE_CODE (arg3) == THROW_EXPR))
result_type = ((TREE_CODE (arg2) == THROW_EXPR)
? arg3_type : arg2_type);
else if (VOID_TYPE_P (arg2_type) && VOID_TYPE_P (arg3_type))
result_type = void_type_node;
else
{
error ("`%E' has type `void' and is not a throw-expression",
VOID_TYPE_P (arg2_type) ? arg2 : arg3);
return error_mark_node;
}
lvalue_p = 0;
goto valid_operands;
}
/* [expr.cond]
Otherwise, if the second and third operand have different types,
and either has (possibly cv-qualified) class type, an attempt is
made to convert each of those operands to the type of the other. */
else if (!same_type_p (arg2_type, arg3_type)
&& (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
{
tree conv2 = conditional_conversion (arg2, arg3);
tree conv3 = conditional_conversion (arg3, arg2);
/* [expr.cond]
If both can be converted, or one can be converted but the
conversion is ambiguous, the program is ill-formed. If
neither can be converted, the operands are left unchanged and
further checking is performed as described below. If exactly
one conversion is possible, that conversion is applied to the
chosen operand and the converted operand is used in place of
the original operand for the remainder of this section. */
if ((conv2 && !ICS_BAD_FLAG (conv2)
&& conv3 && !ICS_BAD_FLAG (conv3))
|| (conv2 && TREE_CODE (conv2) == AMBIG_CONV)
|| (conv3 && TREE_CODE (conv3) == AMBIG_CONV))
{
error ("operands to ?: have different types");
return error_mark_node;
}
else if (conv2 && !ICS_BAD_FLAG (conv2))
{
arg2 = convert_like (conv2, arg2);
arg2 = convert_from_reference (arg2);
/* That may not quite have done the trick. If the two types
are cv-qualified variants of one another, we will have
just used an IDENTITY_CONV. (There's no conversion from
an lvalue of one class type to an lvalue of another type,
even a cv-qualified variant, and we don't want to lose
lvalue-ness here.) So, we manually add a NOP_EXPR here
if necessary. */
if (!same_type_p (TREE_TYPE (arg2), arg3_type))
arg2 = build1 (NOP_EXPR, arg3_type, arg2);
arg2_type = TREE_TYPE (arg2);
}
else if (conv3 && !ICS_BAD_FLAG (conv3))
{
arg3 = convert_like (conv3, arg3);
arg3 = convert_from_reference (arg3);
if (!same_type_p (TREE_TYPE (arg3), arg2_type))
arg3 = build1 (NOP_EXPR, arg2_type, arg3);
arg3_type = TREE_TYPE (arg3);
}
}
/* [expr.cond]
If the second and third operands are lvalues and have the same
type, the result is of that type and is an lvalue. */
if (real_lvalue_p (arg2) && real_lvalue_p (arg3) &&
same_type_p (arg2_type, arg3_type))
{
result_type = arg2_type;
goto valid_operands;
}
/* [expr.cond]
Otherwise, the result is an rvalue. If the second and third
operand do not have the same type, and either has (possibly
cv-qualified) class type, overload resolution is used to
determine the conversions (if any) to be applied to the operands
(_over.match.oper_, _over.built_). */
lvalue_p = 0;
if (!same_type_p (arg2_type, arg3_type)
&& (CLASS_TYPE_P (arg2_type) || CLASS_TYPE_P (arg3_type)))
{
tree args[3];
tree conv;
/* Rearrange the arguments so that add_builtin_candidate only has
to know about two args. In build_builtin_candidates, the
arguments are unscrambled. */
args[0] = arg2;
args[1] = arg3;
args[2] = arg1;
add_builtin_candidates (&candidates,
COND_EXPR,
NOP_EXPR,
ansi_opname (COND_EXPR),
args,
LOOKUP_NORMAL);
/* [expr.cond]
If the overload resolution fails, the program is
ill-formed. */
if (!any_viable (candidates))
{
op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
print_z_candidates (candidates);
return error_mark_node;
}
candidates = splice_viable (candidates);
cand = tourney (candidates);
if (!cand)
{
op_error (COND_EXPR, NOP_EXPR, arg1, arg2, arg3, "no match");
print_z_candidates (candidates);
return error_mark_node;
}
/* [expr.cond]
Otherwise, the conversions thus determined are applied, and
the converted operands are used in place of the original
operands for the remainder of this section. */
conv = TREE_VEC_ELT (cand->convs, 0);
arg1 = convert_like (conv, arg1);
conv = TREE_VEC_ELT (cand->convs, 1);
arg2 = convert_like (conv, arg2);
conv = TREE_VEC_ELT (cand->convs, 2);
arg3 = convert_like (conv, arg3);
}
/* [expr.cond]
Lvalue-to-rvalue (_conv.lval_), array-to-pointer (_conv.array_),
and function-to-pointer (_conv.func_) standard conversions are
performed on the second and third operands.
We need to force the lvalue-to-rvalue conversion here for class types,
so we get TARGET_EXPRs; trying to deal with a COND_EXPR of class rvalues
that isn't wrapped with a TARGET_EXPR plays havoc with exception
regions.
We use ocp_convert rather than build_user_type_conversion because the
latter returns NULL_TREE on failure, while the former gives an error. */
arg2 = force_rvalue (arg2);
arg2_type = TREE_TYPE (arg2);
arg3 = force_rvalue (arg3);
arg3_type = TREE_TYPE (arg3);
if (arg2 == error_mark_node || arg3 == error_mark_node)
return error_mark_node;
/* [expr.cond]
After those conversions, one of the following shall hold:
--The second and third operands have the same type; the result is of
that type. */
if (same_type_p (arg2_type, arg3_type))
result_type = arg2_type;
/* [expr.cond]
--The second and third operands have arithmetic or enumeration
type; the usual arithmetic conversions are performed to bring
them to a common type, and the result is of that type. */
else if ((ARITHMETIC_TYPE_P (arg2_type)
|| TREE_CODE (arg2_type) == ENUMERAL_TYPE)
&& (ARITHMETIC_TYPE_P (arg3_type)
|| TREE_CODE (arg3_type) == ENUMERAL_TYPE))
{
/* In this case, there is always a common type. */
result_type = type_after_usual_arithmetic_conversions (arg2_type,
arg3_type);
if (TREE_CODE (arg2_type) == ENUMERAL_TYPE
&& TREE_CODE (arg3_type) == ENUMERAL_TYPE)
warning ("enumeral mismatch in conditional expression: `%T' vs `%T'",
arg2_type, arg3_type);
else if (extra_warnings
&& ((TREE_CODE (arg2_type) == ENUMERAL_TYPE
&& !same_type_p (arg3_type, type_promotes_to (arg2_type)))
|| (TREE_CODE (arg3_type) == ENUMERAL_TYPE
&& !same_type_p (arg2_type, type_promotes_to (arg3_type)))))
warning ("enumeral and non-enumeral type in conditional expression");
arg2 = perform_implicit_conversion (result_type, arg2);
arg3 = perform_implicit_conversion (result_type, arg3);
}
/* [expr.cond]
--The second and third operands have pointer type, or one has
pointer type and the other is a null pointer constant; pointer
conversions (_conv.ptr_) and qualification conversions
(_conv.qual_) are performed to bring them to their composite
pointer type (_expr.rel_). The result is of the composite
pointer type.
--The second and third operands have pointer to member type, or
one has pointer to member type and the other is a null pointer
constant; pointer to member conversions (_conv.mem_) and
qualification conversions (_conv.qual_) are performed to bring
them to a common type, whose cv-qualification shall match the
cv-qualification of either the second or the third operand.
The result is of the common type. */
else if ((null_ptr_cst_p (arg2)
&& (TYPE_PTR_P (arg3_type) || TYPE_PTRMEM_P (arg3_type)
|| TYPE_PTRMEMFUNC_P (arg3_type)))
|| (null_ptr_cst_p (arg3)
&& (TYPE_PTR_P (arg2_type) || TYPE_PTRMEM_P (arg2_type)
|| TYPE_PTRMEMFUNC_P (arg2_type)))
|| (TYPE_PTR_P (arg2_type) && TYPE_PTR_P (arg3_type))
|| (TYPE_PTRMEM_P (arg2_type) && TYPE_PTRMEM_P (arg3_type))
|| (TYPE_PTRMEMFUNC_P (arg2_type)
&& TYPE_PTRMEMFUNC_P (arg3_type)))
{
result_type = composite_pointer_type (arg2_type, arg3_type, arg2,
arg3, "conditional expression");
arg2 = perform_implicit_conversion (result_type, arg2);
arg3 = perform_implicit_conversion (result_type, arg3);
}
if (!result_type)
{
error ("operands to ?: have different types");
return error_mark_node;
}
valid_operands:
result = fold (build (COND_EXPR, result_type, arg1, arg2, arg3));
/* Expand both sides into the same slot, hopefully the target of the
?: expression. We used to check for TARGET_EXPRs here, but now we
sometimes wrap them in NOP_EXPRs so the test would fail. */
if (!lvalue_p && IS_AGGR_TYPE (result_type))
result = build_target_expr_with_type (result, result_type);
/* If this expression is an rvalue, but might be mistaken for an
lvalue, we must add a NON_LVALUE_EXPR. */
if (!lvalue_p && real_lvalue_p (result))
result = build1 (NON_LVALUE_EXPR, result_type, result);
return result;
}
tree
build_new_op (code, flags, arg1, arg2, arg3)
enum tree_code code;
int flags;
tree arg1, arg2, arg3;
{
struct z_candidate *candidates = 0, *cand;
tree fns, mem_arglist = NULL_TREE, arglist, fnname;
enum tree_code code2 = NOP_EXPR;
tree conv;
bool viable_candidates;
if (arg1 == error_mark_node
|| arg2 == error_mark_node
|| arg3 == error_mark_node)
return error_mark_node;
/* This can happen if a template takes all non-type parameters, e.g.
undeclared_template<1, 5, 72>a; */
if (code == LT_EXPR && TREE_CODE (arg1) == TEMPLATE_DECL)
{
error ("`%D' must be declared before use", arg1);
return error_mark_node;
}
if (code == MODIFY_EXPR)
{
code2 = TREE_CODE (arg3);
arg3 = NULL_TREE;
fnname = ansi_assopname (code2);
}
else
fnname = ansi_opname (code);
if (TREE_CODE (arg1) == OFFSET_REF)
arg1 = resolve_offset_ref (arg1);
arg1 = convert_from_reference (arg1);
if (CLASS_TYPE_P (TREE_TYPE (arg1))
&& CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (arg1)))
/* Make sure the template type is instantiated now. */
instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (arg1)));
switch (code)
{
case NEW_EXPR:
case VEC_NEW_EXPR:
case VEC_DELETE_EXPR:
case DELETE_EXPR:
/* Use build_op_new_call and build_op_delete_call instead. */
abort ();
case CALL_EXPR:
return build_object_call (arg1, arg2);
default:
break;
}
if (arg2)
{
if (TREE_CODE (arg2) == OFFSET_REF)
arg2 = resolve_offset_ref (arg2);
arg2 = convert_from_reference (arg2);
if (CLASS_TYPE_P (TREE_TYPE (arg2))
&& CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (arg2)))
instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (arg2)));
}
if (arg3)
{
if (TREE_CODE (arg3) == OFFSET_REF)
arg3 = resolve_offset_ref (arg3);
arg3 = convert_from_reference (arg3);
if (CLASS_TYPE_P (TREE_TYPE (arg3))
&& CLASSTYPE_TEMPLATE_INSTANTIATION (TREE_TYPE (arg3)))
instantiate_class_template (TYPE_MAIN_VARIANT (TREE_TYPE (arg3)));
}
if (code == COND_EXPR)
{
if (arg2 == NULL_TREE
|| TREE_CODE (TREE_TYPE (arg2)) == VOID_TYPE
|| TREE_CODE (TREE_TYPE (arg3)) == VOID_TYPE
|| (! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))
&& ! IS_OVERLOAD_TYPE (TREE_TYPE (arg3))))
goto builtin;
}
else if (! IS_OVERLOAD_TYPE (TREE_TYPE (arg1))
&& (! arg2 || ! IS_OVERLOAD_TYPE (TREE_TYPE (arg2))))
goto builtin;
if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR)
arg2 = integer_zero_node;
arglist = NULL_TREE;
if (arg3)
arglist = tree_cons (NULL_TREE, arg3, arglist);
if (arg2)
arglist = tree_cons (NULL_TREE, arg2, arglist);
arglist = tree_cons (NULL_TREE, arg1, arglist);
fns = lookup_function_nonclass (fnname, arglist);
if (fns && TREE_CODE (fns) == TREE_LIST)
fns = TREE_VALUE (fns);
for (; fns; fns = OVL_NEXT (fns))
{
tree fn = OVL_CURRENT (fns);
if (TREE_CODE (fn) == TEMPLATE_DECL)
add_template_candidate (&candidates, fn, NULL_TREE, NULL_TREE,
arglist, TREE_TYPE (fnname),
/*access_path=*/NULL_TREE,
/*conversion_path=*/NULL_TREE,
flags, DEDUCE_CALL);
else
add_function_candidate (&candidates, fn, NULL_TREE,
arglist,
/*access_path=*/NULL_TREE,
/*conversion_path=*/NULL_TREE,
flags);
}
if (IS_AGGR_TYPE (TREE_TYPE (arg1)))
{
fns = lookup_fnfields (TYPE_BINFO (TREE_TYPE (arg1)), fnname, 1);
if (fns == error_mark_node)
return fns;
}
else
fns = NULL_TREE;
if (fns)
{
tree conversion_path = BASELINK_BINFO (fns);
mem_arglist = tree_cons (NULL_TREE, build_this (arg1), TREE_CHAIN (arglist));
for (fns = BASELINK_FUNCTIONS (fns); fns; fns = OVL_NEXT (fns))
{
tree fn = OVL_CURRENT (fns);
tree this_arglist;
tree access_path = TYPE_BINFO (TREE_TYPE (arg1));
if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
this_arglist = mem_arglist;
else
this_arglist = arglist;
if (TREE_CODE (fn) == TEMPLATE_DECL)
/* A member template. */
add_template_candidate (&candidates, fn,
BINFO_TYPE (conversion_path),
NULL_TREE,
this_arglist, TREE_TYPE (fnname),
access_path, conversion_path,
flags, DEDUCE_CALL);
else
add_function_candidate
(&candidates, fn, BINFO_TYPE (conversion_path), this_arglist,
access_path, conversion_path, flags);
}
}
{
tree args[3];
/* Rearrange the arguments for ?: so that add_builtin_candidate only has
to know about two args; a builtin candidate will always have a first
parameter of type bool. We'll handle that in
build_builtin_candidate. */
if (code == COND_EXPR)
{
args[0] = arg2;
args[1] = arg3;
args[2] = arg1;
}
else
{
args[0] = arg1;
args[1] = arg2;
args[2] = NULL_TREE;
}
add_builtin_candidates (&candidates, code, code2, fnname, args, flags);
}
switch (code)
{
case COMPOUND_EXPR:
case ADDR_EXPR:
/* For these, the built-in candidates set is empty
[over.match.oper]/3. We don't want non-strict matches
because exact matches are always possible with built-in
operators. The built-in candidate set for COMPONENT_REF
would be empty too, but since there are no such built-in
operators, we accept non-strict matches for them. */
viable_candidates = any_strictly_viable (candidates);
break;
default:
viable_candidates = any_viable (candidates);
break;
}
if (! viable_candidates)
{
switch (code)
{
case POSTINCREMENT_EXPR:
case POSTDECREMENT_EXPR:
/* Look for an `operator++ (int)'. If they didn't have
one, then we fall back to the old way of doing things. */
if (flags & LOOKUP_COMPLAIN)
pedwarn ("no `%D(int)' declared for postfix `%s', trying prefix operator instead",
fnname,
operator_name_info[code].name);
if (code == POSTINCREMENT_EXPR)
code = PREINCREMENT_EXPR;
else
code = PREDECREMENT_EXPR;
return build_new_op (code, flags, arg1, NULL_TREE, NULL_TREE);
/* The caller will deal with these. */
case ADDR_EXPR:
case COMPOUND_EXPR:
case COMPONENT_REF:
return NULL_TREE;
default:
break;
}
if (flags & LOOKUP_COMPLAIN)
{
op_error (code, code2, arg1, arg2, arg3, "no match");
print_z_candidates (candidates);
}
return error_mark_node;
}
candidates = splice_viable (candidates);
cand = tourney (candidates);
if (cand == 0)
{
if (flags & LOOKUP_COMPLAIN)
{
op_error (code, code2, arg1, arg2, arg3, "ambiguous overload");
print_z_candidates (candidates);
}
return error_mark_node;
}
if (TREE_CODE (cand->fn) == FUNCTION_DECL)
{
extern int warn_synth;
if (warn_synth
&& fnname == ansi_assopname (NOP_EXPR)
&& DECL_ARTIFICIAL (cand->fn)
&& candidates->next
&& ! candidates->next->next)
{
warning ("using synthesized `%#D' for copy assignment",
cand->fn);
cp_warning_at (" where cfront would use `%#D'",
cand == candidates
? candidates->next->fn
: candidates->fn);
}
return build_over_call
(cand,
TREE_CODE (TREE_TYPE (cand->fn)) == METHOD_TYPE
? mem_arglist : arglist,
LOOKUP_NORMAL);
}
/* Check for comparison of different enum types. */
switch (code)
{
case GT_EXPR:
case LT_EXPR:
case GE_EXPR:
case LE_EXPR:
case EQ_EXPR:
case NE_EXPR:
if (TREE_CODE (TREE_TYPE (arg1)) == ENUMERAL_TYPE
&& TREE_CODE (TREE_TYPE (arg2)) == ENUMERAL_TYPE
&& (TYPE_MAIN_VARIANT (TREE_TYPE (arg1))
!= TYPE_MAIN_VARIANT (TREE_TYPE (arg2))))
{
warning ("comparison between `%#T' and `%#T'",
TREE_TYPE (arg1), TREE_TYPE (arg2));
}
break;
default:
break;
}
/* We need to strip any leading REF_BIND so that bitfields don't cause
errors. This should not remove any important conversions, because
builtins don't apply to class objects directly. */
conv = TREE_VEC_ELT (cand->convs, 0);
if (TREE_CODE (conv) == REF_BIND)
conv = TREE_OPERAND (conv, 0);
arg1 = convert_like (conv, arg1);
if (arg2)
{
conv = TREE_VEC_ELT (cand->convs, 1);
if (TREE_CODE (conv) == REF_BIND)
conv = TREE_OPERAND (conv, 0);
arg2 = convert_like (conv, arg2);
}
if (arg3)
{
conv = TREE_VEC_ELT (cand->convs, 2);
if (TREE_CODE (conv) == REF_BIND)
conv = TREE_OPERAND (conv, 0);
arg3 = convert_like (conv, arg3);
}
builtin:
switch (code)
{
case MODIFY_EXPR:
return build_modify_expr (arg1, code2, arg2);
case INDIRECT_REF:
return build_indirect_ref (arg1, "unary *");
case PLUS_EXPR:
case MINUS_EXPR:
case MULT_EXPR:
case TRUNC_DIV_EXPR:
case GT_EXPR:
case LT_EXPR:
case GE_EXPR:
case LE_EXPR:
case EQ_EXPR:
case NE_EXPR:
case MAX_EXPR:
case MIN_EXPR:
case LSHIFT_EXPR:
case RSHIFT_EXPR:
case TRUNC_MOD_EXPR:
case BIT_AND_EXPR:
case BIT_IOR_EXPR:
case BIT_XOR_EXPR:
case TRUTH_ANDIF_EXPR:
case TRUTH_ORIF_EXPR:
return cp_build_binary_op (code, arg1, arg2);
case CONVERT_EXPR:
case NEGATE_EXPR:
case BIT_NOT_EXPR:
case TRUTH_NOT_EXPR:
case PREINCREMENT_EXPR:
case POSTINCREMENT_EXPR:
case PREDECREMENT_EXPR:
case POSTDECREMENT_EXPR:
case REALPART_EXPR:
case IMAGPART_EXPR:
return build_unary_op (code, arg1, candidates != 0);
case ARRAY_REF:
return build_array_ref (arg1, arg2);
case COND_EXPR:
return build_conditional_expr (arg1, arg2, arg3);
case MEMBER_REF:
return build_m_component_ref
(build_indirect_ref (arg1, NULL), arg2);
/* The caller will deal with these. */
case ADDR_EXPR:
case COMPONENT_REF:
case COMPOUND_EXPR:
return NULL_TREE;
default:
abort ();
return NULL_TREE;
}
}
/* Build a call to operator delete. This has to be handled very specially,
because the restrictions on what signatures match are different from all
other call instances. For a normal delete, only a delete taking (void *)
or (void *, size_t) is accepted. For a placement delete, only an exact
match with the placement new is accepted.
CODE is either DELETE_EXPR or VEC_DELETE_EXPR.
ADDR is the pointer to be deleted.
SIZE is the size of the memory block to be deleted.
FLAGS are the usual overloading flags.
PLACEMENT is the corresponding placement new call, or NULL_TREE. */
tree
build_op_delete_call (code, addr, size, flags, placement)
enum tree_code code;
tree addr, size, placement;
int flags;
{
tree fn = NULL_TREE;
tree fns, fnname, fntype, argtypes, args, type;
int pass;
if (addr == error_mark_node)
return error_mark_node;
type = TREE_TYPE (TREE_TYPE (addr));
while (TREE_CODE (type) == ARRAY_TYPE)
type = TREE_TYPE (type);
fnname = ansi_opname (code);
if (IS_AGGR_TYPE (type) && ! (flags & LOOKUP_GLOBAL))
/* In [class.free]
If the result of the lookup is ambiguous or inaccessible, or if
the lookup selects a placement deallocation function, the
program is ill-formed.
Therefore, we ask lookup_fnfields to complain ambout ambiguity. */
{
fns = lookup_fnfields (TYPE_BINFO (type), fnname, 1);
if (fns == error_mark_node)
return error_mark_node;
}
else
fns = NULL_TREE;
if (fns == NULL_TREE)
fns = lookup_name_nonclass (fnname);
if (placement)
{
tree alloc_fn;
tree call_expr;
/* Find the allocation function that is being called. */
call_expr = placement;
/* Sometimes we have a COMPOUND_EXPR, rather than a simple
CALL_EXPR. */
while (TREE_CODE (call_expr) == COMPOUND_EXPR)
call_expr = TREE_OPERAND (call_expr, 1);
/* Extract the function. */
alloc_fn = get_callee_fndecl (call_expr);
my_friendly_assert (alloc_fn != NULL_TREE, 20020327);
/* Then the second parm type. */
argtypes = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
/* Also the second argument. */
args = TREE_CHAIN (TREE_OPERAND (call_expr, 1));
}
else
{
/* First try it without the size argument. */
argtypes = void_list_node;
args = NULL_TREE;
}
/* Strip const and volatile from addr. */
addr = cp_convert (ptr_type_node, addr);
/* We make two tries at finding a matching `operator delete'. On
the first pass, we look for an one-operator (or placement)
operator delete. If we're not doing placement delete, then on
the second pass we look for a two-argument delete. */
for (pass = 0; pass < (placement ? 1 : 2); ++pass)
{
if (pass == 0)
argtypes = tree_cons (NULL_TREE, ptr_type_node, argtypes);
else
/* Normal delete; now try to find a match including the size
argument. */
argtypes = tree_cons (NULL_TREE, ptr_type_node,
tree_cons (NULL_TREE, sizetype,
void_list_node));
fntype = build_function_type (void_type_node, argtypes);
/* Go through the `operator delete' functions looking for one
with a matching type. */
for (fn = BASELINK_P (fns) ? BASELINK_FUNCTIONS (fns) : fns;
fn;
fn = OVL_NEXT (fn))
{
tree t;
/* Exception specifications on the `delete' operator do not
matter. */
t = build_exception_variant (TREE_TYPE (OVL_CURRENT (fn)),
NULL_TREE);
/* We also don't compare attributes. We're really just
trying to check the types of the first two parameters. */
if (comptypes (t, fntype, COMPARE_NO_ATTRIBUTES))
break;
}
/* If we found a match, we're done. */
if (fn)
break;
}
/* If we have a matching function, call it. */
if (fn)
{
/* Make sure we have the actual function, and not an
OVERLOAD. */
fn = OVL_CURRENT (fn);
/* If the FN is a member function, make sure that it is
accessible. */
if (DECL_CLASS_SCOPE_P (fn))
enforce_access (type, fn);
if (pass == 0)
args = tree_cons (NULL_TREE, addr, args);
else
args = tree_cons (NULL_TREE, addr,
build_tree_list (NULL_TREE, size));
return build_function_call (fn, args);
}
/* If we are doing placement delete we do nothing if we don't find a
matching op delete. */
if (placement)
return NULL_TREE;
error ("no suitable `operator delete' for `%T'", type);
return error_mark_node;
}
/* If the current scope isn't allowed to access DECL along
BASETYPE_PATH, give an error. The most derived class in
BASETYPE_PATH is the one used to qualify DECL. */
int
enforce_access (basetype_path, decl)
tree basetype_path;
tree decl;
{
int accessible;
accessible = accessible_p (basetype_path, decl);
if (!accessible)
{
if (TREE_PRIVATE (decl))
cp_error_at ("`%+#D' is private", decl);
else if (TREE_PROTECTED (decl))
cp_error_at ("`%+#D' is protected", decl);
else
cp_error_at ("`%+#D' is inaccessible", decl);
error ("within this context");
return 0;
}
return 1;
}
/* Perform the conversions in CONVS on the expression EXPR. FN and
ARGNUM are used for diagnostics. ARGNUM is zero based, -1
indicates the `this' argument of a method. INNER is nonzero when
being called to continue a conversion chain. It is negative when a
reference binding will be applied, positive otherwise. If
ISSUE_CONVERSION_WARNINGS is true, warnings about suspicious
conversions will be emitted if appropriate. */
static tree
convert_like_real (tree convs, tree expr, tree fn, int argnum, int inner,
bool issue_conversion_warnings)
{
int savew, savee;
tree totype = TREE_TYPE (convs);
if (ICS_BAD_FLAG (convs)
&& TREE_CODE (convs) != USER_CONV
&& TREE_CODE (convs) != AMBIG_CONV
&& TREE_CODE (convs) != REF_BIND)
{
tree t = convs;
for (; t; t = TREE_OPERAND (t, 0))
{
if (TREE_CODE (t) == USER_CONV || !ICS_BAD_FLAG (t))
{
expr = convert_like_real (t, expr, fn, argnum, 1,
/*issue_conversion_warnings=*/false);
break;
}
else if (TREE_CODE (t) == AMBIG_CONV)
return convert_like_real (t, expr, fn, argnum, 1,
/*issue_conversion_warnings=*/false);
else if (TREE_CODE (t) == IDENTITY_CONV)
break;
}
pedwarn ("invalid conversion from `%T' to `%T'", TREE_TYPE (expr), totype);
if (fn)
pedwarn (" initializing argument %P of `%D'", argnum, fn);
return cp_convert (totype, expr);
}
if (issue_conversion_warnings)
expr = dubious_conversion_warnings
(totype, expr, "argument", fn, argnum);
switch (TREE_CODE (convs))
{
case USER_CONV:
{
struct z_candidate *cand = USER_CONV_CAND (convs);
tree convfn = cand->fn;
tree args;
if (DECL_CONSTRUCTOR_P (convfn))
{
tree t = build_int_2 (0, 0);
TREE_TYPE (t) = build_pointer_type (DECL_CONTEXT (convfn));
args = build_tree_list (NULL_TREE, expr);
if (DECL_HAS_IN_CHARGE_PARM_P (convfn)
|| DECL_HAS_VTT_PARM_P (convfn))
/* We should never try to call the abstract or base constructor
from here. */
abort ();
args = tree_cons (NULL_TREE, t, args);
}
else
args = build_this (expr);
expr = build_over_call (cand, args, LOOKUP_NORMAL);
/* If this is a constructor or a function returning an aggr type,
we need to build up a TARGET_EXPR. */
if (DECL_CONSTRUCTOR_P (convfn))
expr = build_cplus_new (totype, expr);
/* The result of the call is then used to direct-initialize the object
that is the destination of the copy-initialization. [dcl.init]
Note that this step is not reflected in the conversion sequence;
it affects the semantics when we actually perform the
conversion, but is not considered during overload resolution.
If the target is a class, that means call a ctor. */
if (IS_AGGR_TYPE (totype)
&& (inner >= 0 || !lvalue_p (expr)))
{
savew = warningcount, savee = errorcount;
expr = build_special_member_call
(NULL_TREE, complete_ctor_identifier,
build_tree_list (NULL_TREE, expr), TYPE_BINFO (totype),
/* Core issue 84, now a DR, says that we don't allow UDCs
for these args (which deliberately breaks copy-init of an
auto_ptr<Base> from an auto_ptr<Derived>). */
LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING|LOOKUP_NO_CONVERSION);
/* Tell the user where this failing constructor call came from. */
if (fn)
{
if (warningcount > savew)
warning
(" initializing argument %P of `%D' from result of `%D'",
argnum, fn, convfn);
else if (errorcount > savee)
error
(" initializing argument %P of `%D' from result of `%D'",
argnum, fn, convfn);
}
else
{
if (warningcount > savew)
warning (" initializing temporary from result of `%D'",
convfn);
else if (errorcount > savee)
error (" initializing temporary from result of `%D'",
convfn);
}
expr = build_cplus_new (totype, expr);
}
return expr;
}
case IDENTITY_CONV:
if (type_unknown_p (expr))
expr = instantiate_type (totype, expr, tf_error | tf_warning);
return expr;
case AMBIG_CONV:
/* Call build_user_type_conversion again for the error. */
return build_user_type_conversion
(totype, TREE_OPERAND (convs, 0), LOOKUP_NORMAL);
default:
break;
};
expr = convert_like_real (TREE_OPERAND (convs, 0), expr, fn, argnum,
TREE_CODE (convs) == REF_BIND ? -1 : 1,
/*issue_conversion_warnings=*/false);
if (expr == error_mark_node)
return error_mark_node;
/* Convert a non-array constant variable to its underlying value, unless we
are about to bind it to a reference, in which case we need to
leave it as an lvalue. */
if (TREE_CODE (convs) != REF_BIND
&& TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
expr = decl_constant_value (expr);
switch (TREE_CODE (convs))
{
case RVALUE_CONV:
if (! IS_AGGR_TYPE (totype))
return expr;
/* else fall through */
case BASE_CONV:
if (TREE_CODE (convs) == BASE_CONV && !NEED_TEMPORARY_P (convs))
{
/* We are going to bind a reference directly to a base-class
subobject of EXPR. */
tree base_ptr = build_pointer_type (totype);
/* Build an expression for `*((base*) &expr)'. */
expr = build_unary_op (ADDR_EXPR, expr, 0);
expr = perform_implicit_conversion (base_ptr, expr);
expr = build_indirect_ref (expr, "implicit conversion");
return expr;
}
/* Copy-initialization where the cv-unqualified version of the source
type is the same class as, or a derived class of, the class of the
destination [is treated as direct-initialization]. [dcl.init] */
savew = warningcount, savee = errorcount;
expr = build_special_member_call (NULL_TREE, complete_ctor_identifier,
build_tree_list (NULL_TREE, expr),
TYPE_BINFO (totype),
LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING);
if (fn)
{
if (warningcount > savew)
warning (" initializing argument %P of `%D'", argnum, fn);
else if (errorcount > savee)
error (" initializing argument %P of `%D'", argnum, fn);
}
return build_cplus_new (totype, expr);
case REF_BIND:
{
tree ref_type = totype;
/* If necessary, create a temporary. */
if (NEED_TEMPORARY_P (convs) || !non_cast_lvalue_p (expr))
{
tree type = TREE_TYPE (TREE_OPERAND (convs, 0));
expr = build_target_expr_with_type (expr, type);
}
/* Take the address of the thing to which we will bind the
reference. */
expr = build_unary_op (ADDR_EXPR, expr, 1);
if (expr == error_mark_node)
return error_mark_node;
/* Convert it to a pointer to the type referred to by the
reference. This will adjust the pointer if a derived to
base conversion is being performed. */
expr = cp_convert (build_pointer_type (TREE_TYPE (ref_type)),
expr);
/* Convert the pointer to the desired reference type. */
return build_nop (ref_type, expr);
}
case LVALUE_CONV:
return decay_conversion (expr);
case QUAL_CONV:
/* Warn about deprecated conversion if appropriate. */
string_conv_p (totype, expr, 1);
break;
default:
break;
}
return ocp_convert (totype, expr, CONV_IMPLICIT,
LOOKUP_NORMAL|LOOKUP_NO_CONVERSION);
}
/* Build a call to __builtin_trap which can be used in an expression. */
static tree
call_builtin_trap ()
{
tree fn = get_identifier ("__builtin_trap");
if (IDENTIFIER_GLOBAL_VALUE (fn))
fn = IDENTIFIER_GLOBAL_VALUE (fn);
else
abort ();
fn = build_call (fn, NULL_TREE);
fn = build (COMPOUND_EXPR, integer_type_node, fn, integer_zero_node);
return fn;
}
/* ARG is being passed to a varargs function. Perform any conversions
required. Array/function to pointer decay must have already happened.
Return the converted value. */
tree
convert_arg_to_ellipsis (arg)
tree arg;
{
if (TREE_CODE (TREE_TYPE (arg)) == REAL_TYPE
&& (TYPE_PRECISION (TREE_TYPE (arg))
< TYPE_PRECISION (double_type_node)))
/* Convert `float' to `double'. */
arg = cp_convert (double_type_node, arg);
else
/* Convert `short' and `char' to full-size `int'. */
arg = default_conversion (arg);
arg = require_complete_type (arg);
if (arg != error_mark_node && ! pod_type_p (TREE_TYPE (arg)))
{
/* Undefined behavior [expr.call] 5.2.2/7. We used to just warn
here and do a bitwise copy, but now cp_expr_size will abort if we
try to do that. */
warning ("cannot pass objects of non-POD type `%#T' through `...'; \
call will abort at runtime",
TREE_TYPE (arg));
arg = call_builtin_trap ();
}
return arg;
}
/* va_arg (EXPR, TYPE) is a builtin. Make sure it is not abused. */
tree
build_x_va_arg (expr, type)
tree expr;
tree type;
{
if (processing_template_decl)
return build_min (VA_ARG_EXPR, type, expr);
type = complete_type_or_else (type, NULL_TREE);
if (expr == error_mark_node || !type)
return error_mark_node;
if (! pod_type_p (type))
{
/* Undefined behavior [expr.call] 5.2.2/7. */
warning ("cannot receive objects of non-POD type `%#T' through `...'",
type);
}
return build_va_arg (expr, type);
}
/* TYPE has been given to va_arg. Apply the default conversions which
would have happened when passed via ellipsis. Return the promoted
type, or the passed type if there is no change. */
tree
cxx_type_promotes_to (type)
tree type;
{
tree promote;
if (TREE_CODE (type) == ARRAY_TYPE)
return build_pointer_type (TREE_TYPE (type));
if (TREE_CODE (type) == FUNCTION_TYPE)
return build_pointer_type (type);
promote = type_promotes_to (type);
if (same_type_p (type, promote))
promote = type;
return promote;
}
/* ARG is a default argument expression being passed to a parameter of
the indicated TYPE, which is a parameter to FN. Do any required
conversions. Return the converted value. */
tree
convert_default_arg (type, arg, fn, parmnum)
tree type;
tree arg;
tree fn;
int parmnum;
{
if (TREE_CODE (arg) == DEFAULT_ARG)
{
/* When processing the default args for a class, we can find that
there is an ordering constraint, and we call a function who's
default args have not yet been converted. For instance,
class A {
A (int = 0);
void Foo (A const & = A ());
};
We must process A::A before A::Foo's default arg can be converted.
Remember the dependent function, so do_pending_defargs can retry,
and check loops. */
unprocessed_defarg_fn (fn);
/* Don't return error_mark node, as we won't be able to distinguish
genuine errors from this case, and that would lead to repeated
diagnostics. Just make something of the right type. */
return build1 (NOP_EXPR, type, integer_zero_node);
}
if (fn && DECL_TEMPLATE_INFO (fn))
arg = tsubst_default_argument (fn, type, arg);
arg = break_out_target_exprs (arg);
if (TREE_CODE (arg) == CONSTRUCTOR)
{
arg = digest_init (type, arg, 0);
arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
"default argument", fn, parmnum);
}
else
{
/* This could get clobbered by the following call. */
if (TREE_HAS_CONSTRUCTOR (arg))
arg = copy_node (arg);
arg = convert_for_initialization (0, type, arg, LOOKUP_NORMAL,
"default argument", fn, parmnum);
arg = convert_for_arg_passing (type, arg);
}
return arg;
}
/* Returns the type which will really be used for passing an argument of
type TYPE. */
tree
type_passed_as (type)
tree type;
{
/* Pass classes with copy ctors by invisible reference. */
if (TREE_ADDRESSABLE (type))
type = build_reference_type (type);
else if (PROMOTE_PROTOTYPES
&& INTEGRAL_TYPE_P (type)
&& TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
type = integer_type_node;
return type;
}
/* Actually perform the appropriate conversion. */
tree
convert_for_arg_passing (type, val)
tree type, val;
{
if (val == error_mark_node)
;
/* Pass classes with copy ctors by invisible reference. */
else if (TREE_ADDRESSABLE (type))
val = build1 (ADDR_EXPR, build_reference_type (type), val);
else if (PROMOTE_PROTOTYPES
&& INTEGRAL_TYPE_P (type)
&& TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
val = default_conversion (val);
return val;
}
/* Subroutine of the various build_*_call functions. Overload resolution
has chosen a winning candidate CAND; build up a CALL_EXPR accordingly.
ARGS is a TREE_LIST of the unconverted arguments to the call. FLAGS is a
bitmask of various LOOKUP_* flags which apply to the call itself. */
static tree
build_over_call (cand, args, flags)
struct z_candidate *cand;
tree args;
int flags;
{
tree fn = cand->fn;
tree convs = cand->convs;
tree converted_args = NULL_TREE;
tree parm = TYPE_ARG_TYPES (TREE_TYPE (fn));
tree conv, arg, val;
int i = 0;
int is_method = 0;
/* Give any warnings we noticed during overload resolution. */
if (cand->warnings)
for (val = cand->warnings; val; val = TREE_CHAIN (val))
joust (cand, WRAPPER_ZC (TREE_VALUE (val)), 1);
if (DECL_FUNCTION_MEMBER_P (fn))
enforce_access (cand->access_path, fn);
if (args && TREE_CODE (args) != TREE_LIST)
args = build_tree_list (NULL_TREE, args);
arg = args;
/* The implicit parameters to a constructor are not considered by overload
resolution, and must be of the proper type. */
if (DECL_CONSTRUCTOR_P (fn))
{
converted_args = tree_cons (NULL_TREE, TREE_VALUE (arg), converted_args);
arg = TREE_CHAIN (arg);
parm = TREE_CHAIN (parm);
if (DECL_HAS_IN_CHARGE_PARM_P (fn))
/* We should never try to call the abstract constructor. */
abort ();
if (DECL_HAS_VTT_PARM_P (fn))
{
converted_args = tree_cons
(NULL_TREE, TREE_VALUE (arg), converted_args);
arg = TREE_CHAIN (arg);
parm = TREE_CHAIN (parm);
}
}
/* Bypass access control for 'this' parameter. */
else if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
{
tree parmtype = TREE_VALUE (parm);
tree argtype = TREE_TYPE (TREE_VALUE (arg));
tree converted_arg;
tree base_binfo;
if (ICS_BAD_FLAG (TREE_VEC_ELT (convs, i)))
pedwarn ("passing `%T' as `this' argument of `%#D' discards qualifiers",
TREE_TYPE (argtype), fn);
/* [class.mfct.nonstatic]: If a nonstatic member function of a class
X is called for an object that is not of type X, or of a type
derived from X, the behavior is undefined.
So we can assume that anything passed as 'this' is non-null, and
optimize accordingly. */
my_friendly_assert (TREE_CODE (parmtype) == POINTER_TYPE, 19990811);
/* Convert to the base in which the function was declared. */
my_friendly_assert (cand->conversion_path != NULL_TREE, 20020730);
converted_arg = build_base_path (PLUS_EXPR,
TREE_VALUE (arg),
cand->conversion_path,
1);
/* Check that the base class is accessible. */
if (!accessible_base_p (TREE_TYPE (argtype),
BINFO_TYPE (cand->conversion_path)))
error ("`%T' is not an accessible base of `%T'",
BINFO_TYPE (cand->conversion_path),
TREE_TYPE (argtype));
/* If fn was found by a using declaration, the conversion path
will be to the derived class, not the base declaring fn. We
must convert from derived to base. */
base_binfo = lookup_base (TREE_TYPE (TREE_TYPE (converted_arg)),
TREE_TYPE (parmtype), ba_ignore, NULL);
converted_arg = build_base_path (PLUS_EXPR, converted_arg,
base_binfo, 1);
converted_args = tree_cons (NULL_TREE, converted_arg, converted_args);
parm = TREE_CHAIN (parm);
arg = TREE_CHAIN (arg);
++i;
is_method = 1;
}
for (; arg && parm;
parm = TREE_CHAIN (parm), arg = TREE_CHAIN (arg), ++i)
{
tree type = TREE_VALUE (parm);
conv = TREE_VEC_ELT (convs, i);
val = convert_like_with_context
(conv, TREE_VALUE (arg), fn, i - is_method);
val = convert_for_arg_passing (type, val);
converted_args = tree_cons (NULL_TREE, val, converted_args);
}
/* Default arguments */
for (; parm && parm != void_list_node; parm = TREE_CHAIN (parm), i++)
converted_args
= tree_cons (NULL_TREE,
convert_default_arg (TREE_VALUE (parm),
TREE_PURPOSE (parm),
fn, i - is_method),
converted_args);
/* Ellipsis */
for (; arg; arg = TREE_CHAIN (arg))
converted_args
= tree_cons (NULL_TREE,
convert_arg_to_ellipsis (TREE_VALUE (arg)),
converted_args);
converted_args = nreverse (converted_args);
if (warn_format)
check_function_format (NULL, TYPE_ATTRIBUTES (TREE_TYPE (fn)),
converted_args);
/* Avoid actually calling copy constructors and copy assignment operators,
if possible. */
if (! flag_elide_constructors)
/* Do things the hard way. */;
else if (TREE_VEC_LENGTH (convs) == 1
&& DECL_COPY_CONSTRUCTOR_P (fn))
{
tree targ;
arg = skip_artificial_parms_for (fn, converted_args);
arg = TREE_VALUE (arg);
/* Pull out the real argument, disregarding const-correctness. */
targ = arg;
while (TREE_CODE (targ) == NOP_EXPR
|| TREE_CODE (targ) == NON_LVALUE_EXPR
|| TREE_CODE (targ) == CONVERT_EXPR)
targ = TREE_OPERAND (targ, 0);
if (TREE_CODE (targ) == ADDR_EXPR)
{
targ = TREE_OPERAND (targ, 0);
if (!same_type_ignoring_top_level_qualifiers_p
(TREE_TYPE (TREE_TYPE (arg)), TREE_TYPE (targ)))
targ = NULL_TREE;
}
else
targ = NULL_TREE;
if (targ)
arg = targ;
else
arg = build_indirect_ref (arg, 0);
/* [class.copy]: the copy constructor is implicitly defined even if
the implementation elided its use. */
if (TYPE_HAS_COMPLEX_INIT_REF (DECL_CONTEXT (fn)))
mark_used (fn);
/* If we're creating a temp and we already have one, don't create a
new one. If we're not creating a temp but we get one, use
INIT_EXPR to collapse the temp into our target. Otherwise, if the
ctor is trivial, do a bitwise copy with a simple TARGET_EXPR for a
temp or an INIT_EXPR otherwise. */
if (integer_zerop (TREE_VALUE (args)))
{
if (TREE_CODE (arg) == TARGET_EXPR)
return arg;
else if (TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
return build_target_expr_with_type (arg, DECL_CONTEXT (fn));
}
else if (TREE_CODE (arg) == TARGET_EXPR
|| TYPE_HAS_TRIVIAL_INIT_REF (DECL_CONTEXT (fn)))
{
tree address;
tree to = stabilize_reference
(build_indirect_ref (TREE_VALUE (args), 0));
val = build (INIT_EXPR, DECL_CONTEXT (fn), to, arg);
address = build_unary_op (ADDR_EXPR, val, 0);
/* Avoid a warning about this expression, if the address is
never used. */
TREE_USED (address) = 1;
return address;
}
}
else if (DECL_OVERLOADED_OPERATOR_P (fn) == NOP_EXPR
&& copy_fn_p (fn)
&& TYPE_HAS_TRIVIAL_ASSIGN_REF (DECL_CONTEXT (fn)))
{
tree to = stabilize_reference
(build_indirect_ref (TREE_VALUE (converted_args), 0));
arg = build_indirect_ref (TREE_VALUE (TREE_CHAIN (converted_args)), 0);
val = build (MODIFY_EXPR, TREE_TYPE (to), to, arg);
return val;
}
mark_used (fn);
if (DECL_VINDEX (fn) && (flags & LOOKUP_NONVIRTUAL) == 0)
{
tree t, *p = &TREE_VALUE (converted_args);
tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (*p)),
DECL_CONTEXT (fn),
ba_any, NULL);
my_friendly_assert (binfo && binfo != error_mark_node, 20010730);
*p = build_base_path (PLUS_EXPR, *p, binfo, 1);
if (TREE_SIDE_EFFECTS (*p))
*p = save_expr (*p);
t = build_pointer_type (TREE_TYPE (fn));
if (DECL_CONTEXT (fn) && TYPE_JAVA_INTERFACE (DECL_CONTEXT (fn)))
fn = build_java_interface_fn_ref (fn, *p);
else
fn = build_vfn_ref (build_indirect_ref (*p, 0), DECL_VINDEX (fn));
TREE_TYPE (fn) = t;
}
else if (DECL_INLINE (fn))
fn = inline_conversion (fn);
else
fn = build_addr_func (fn);
return build_cxx_call (fn, args, converted_args);
}
/* Build and return a call to FN, using the the CONVERTED_ARGS. ARGS
gives the original form of the arguments. This function performs
no overload resolution, conversion, or other high-level
operations. */
tree
build_cxx_call(tree fn, tree args, tree converted_args)
{
tree fndecl;
/* Recognize certain built-in functions so we can make tree-codes
other than CALL_EXPR. We do this when it enables fold-const.c
to do something useful. */
if (TREE_CODE (fn) == ADDR_EXPR
&& TREE_CODE (TREE_OPERAND (fn, 0)) == FUNCTION_DECL
&& DECL_BUILT_IN (TREE_OPERAND (fn, 0)))
{
tree exp;
exp = expand_tree_builtin (TREE_OPERAND (fn, 0), args, converted_args);
if (exp)
return exp;
}
fn = build_call (fn, converted_args);
/* If this call might throw an exception, note that fact. */
fndecl = get_callee_fndecl (fn);
if ((!fndecl || !TREE_NOTHROW (fndecl))
&& at_function_scope_p ()
&& cfun)
cp_function_chain->can_throw = 1;
/* Some built-in function calls will be evaluated at compile-time in
fold (). */
fn = fold (fn);
if (VOID_TYPE_P (TREE_TYPE (fn)))
return fn;
fn = require_complete_type (fn);
if (fn == error_mark_node)
return error_mark_node;
if (IS_AGGR_TYPE (TREE_TYPE (fn)))
fn = build_cplus_new (TREE_TYPE (fn), fn);
return convert_from_reference (fn);
}
static GTY(()) tree java_iface_lookup_fn;
/* Make an expression which yields the address of the Java interface
method FN. This is achieved by generating a call to libjava's
_Jv_LookupInterfaceMethodIdx(). */
static tree
build_java_interface_fn_ref (fn, instance)
tree fn, instance;
{
tree lookup_args, lookup_fn, method, idx;
tree klass_ref, iface, iface_ref;
int i;
if (!java_iface_lookup_fn)
{
tree endlink = build_void_list_node ();
tree t = tree_cons (NULL_TREE, ptr_type_node,
tree_cons (NULL_TREE, ptr_type_node,
tree_cons (NULL_TREE, java_int_type_node,
endlink)));
java_iface_lookup_fn
= builtin_function ("_Jv_LookupInterfaceMethodIdx",
build_function_type (ptr_type_node, t),
0, NOT_BUILT_IN, NULL, NULL_TREE);
}
/* Look up the pointer to the runtime java.lang.Class object for `instance'.
This is the first entry in the vtable. */
klass_ref = build_vtbl_ref (build_indirect_ref (instance, 0),
integer_zero_node);
/* Get the java.lang.Class pointer for the interface being called. */
iface = DECL_CONTEXT (fn);
iface_ref = lookup_field (iface, get_identifier ("class$"), 0, 0);
if (!iface_ref || TREE_CODE (iface_ref) != VAR_DECL
|| DECL_CONTEXT (iface_ref) != iface)
{
error ("could not find class$ field in java interface type `%T'",
iface);
return error_mark_node;
}
iface_ref = build1 (ADDR_EXPR, build_pointer_type (iface), iface_ref);
/* Determine the itable index of FN. */
i = 1;
for (method = TYPE_METHODS (iface); method; method = TREE_CHAIN (method))
{
if (!DECL_VIRTUAL_P (method))
continue;
if (fn == method)
break;
i++;
}
idx = build_int_2 (i, 0);
lookup_args = tree_cons (NULL_TREE, klass_ref,
tree_cons (NULL_TREE, iface_ref,
build_tree_list (NULL_TREE, idx)));
lookup_fn = build1 (ADDR_EXPR,
build_pointer_type (TREE_TYPE (java_iface_lookup_fn)),
java_iface_lookup_fn);
return build (CALL_EXPR, ptr_type_node, lookup_fn, lookup_args, NULL_TREE);
}
/* Returns the value to use for the in-charge parameter when making a
call to a function with the indicated NAME. */
tree
in_charge_arg_for_name (name)
tree name;
{
if (name == base_ctor_identifier
|| name == base_dtor_identifier)
return integer_zero_node;
else if (name == complete_ctor_identifier)
return integer_one_node;
else if (name == complete_dtor_identifier)
return integer_two_node;
else if (name == deleting_dtor_identifier)
return integer_three_node;
/* This function should only be called with one of the names listed
above. */
abort ();
return NULL_TREE;
}
/* Build a call to a constructor, destructor, or an assignment
operator for INSTANCE, an expression with class type. NAME
indicates the special member function to call; ARGS are the
arguments. BINFO indicates the base of INSTANCE that is to be
passed as the `this' parameter to the member function called.
FLAGS are the LOOKUP_* flags to use when processing the call.
If NAME indicates a complete object constructor, INSTANCE may be
NULL_TREE. In this case, the caller will call build_cplus_new to
store the newly constructed object into a VAR_DECL. */
tree
build_special_member_call (tree instance, tree name, tree args,
tree binfo, int flags)
{
tree fns;
/* The type of the subobject to be constructed or destroyed. */
tree class_type;
my_friendly_assert (name == complete_ctor_identifier
|| name == base_ctor_identifier
|| name == complete_dtor_identifier
|| name == base_dtor_identifier
|| name == deleting_dtor_identifier
|| name == ansi_assopname (NOP_EXPR),
20020712);
my_friendly_assert (binfo != NULL_TREE, 20020712);
class_type = BINFO_TYPE (binfo);
/* Handle the special case where INSTANCE is NULL_TREE. */
if (name == complete_ctor_identifier && !instance)
{
instance = build_int_2 (0, 0);
TREE_TYPE (instance) = build_pointer_type (class_type);
instance = build1 (INDIRECT_REF, class_type, instance);
}
else
{
if (name == complete_dtor_identifier
|| name == base_dtor_identifier
|| name == deleting_dtor_identifier)
my_friendly_assert (args == NULL_TREE, 20020712);
/* We must perform the conversion here so that we do not
subsequently check to see whether BINFO is an accessible
base. (It is OK for a constructor to call a constructor in
an inaccessible base as long as the constructor being called
is accessible.) */
if (!same_type_ignoring_top_level_qualifiers_p
(TREE_TYPE (instance), BINFO_TYPE (binfo)))
instance = convert_to_base_statically (instance, binfo);
}
my_friendly_assert (instance != NULL_TREE, 20020712);
/* Resolve the name. */
if (!complete_type_or_else (BINFO_TYPE (binfo), NULL_TREE))
return error_mark_node;
fns = lookup_fnfields (binfo, name, 1);
/* When making a call to a constructor or destructor for a subobject
that uses virtual base classes, pass down a pointer to a VTT for
the subobject. */
if ((name == base_ctor_identifier
|| name == base_dtor_identifier)
&& TYPE_USES_VIRTUAL_BASECLASSES (class_type))
{
tree vtt;
tree sub_vtt;
/* If the current function is a complete object constructor
or destructor, then we fetch the VTT directly.
Otherwise, we look it up using the VTT we were given. */
vtt = TREE_CHAIN (CLASSTYPE_VTABLES (current_class_type));
vtt = decay_conversion (vtt);
vtt = build (COND_EXPR, TREE_TYPE (vtt),
build (EQ_EXPR, boolean_type_node,
current_in_charge_parm, integer_zero_node),
current_vtt_parm,
vtt);
if (TREE_VIA_VIRTUAL (binfo))
binfo = binfo_for_vbase (class_type, current_class_type);
my_friendly_assert (BINFO_SUBVTT_INDEX (binfo), 20010110);
sub_vtt = build (PLUS_EXPR, TREE_TYPE (vtt), vtt,
BINFO_SUBVTT_INDEX (binfo));
args = tree_cons (NULL_TREE, sub_vtt, args);
}
return build_new_method_call (instance, fns, args,
TYPE_BINFO (BINFO_TYPE (binfo)),
flags);
}
/* Build a call to "INSTANCE.FN (ARGS)". */
tree
build_new_method_call (tree instance, tree fns, tree args,
tree conversion_path, int flags)
{
struct z_candidate *candidates = 0, *cand;
tree explicit_targs = NULL_TREE;
tree basetype = NULL_TREE;
tree access_binfo;
tree optype;
tree mem_args = NULL_TREE, instance_ptr;
tree name, pretty_name;
tree user_args;
tree call;
int template_only = 0;
my_friendly_assert (instance != NULL_TREE, 20020729);
if (instance == error_mark_node || fns == error_mark_node
|| args == error_mark_node)
return error_mark_node;
/* Process the argument list. */
user_args = args;
args = resolve_args (args);
if (args == error_mark_node)
return error_mark_node;
if (TREE_CODE (instance) == OFFSET_REF)
instance = resolve_offset_ref (instance);
if (TREE_CODE (TREE_TYPE (instance)) == REFERENCE_TYPE)
instance = convert_from_reference (instance);
basetype = TYPE_MAIN_VARIANT (TREE_TYPE (instance));
instance_ptr = build_this (instance);
if (!BASELINK_P (fns))
{
call = build_field_call (instance_ptr, fns, args);
if (call)
return call;
error ("call to non-function `%D'", fns);
return error_mark_node;
}
if (!conversion_path)
conversion_path = BASELINK_BINFO (fns);
access_binfo = BASELINK_ACCESS_BINFO (fns);
optype = BASELINK_OPTYPE (fns);
fns = BASELINK_FUNCTIONS (fns);
if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
{
explicit_targs = TREE_OPERAND (fns, 1);
fns = TREE_OPERAND (fns, 0);
template_only = 1;
}
my_friendly_assert (TREE_CODE (fns) == FUNCTION_DECL
|| TREE_CODE (fns) == TEMPLATE_DECL
|| TREE_CODE (fns) == OVERLOAD,
20020712);
/* XXX this should be handled before we get here. */
if (! IS_AGGR_TYPE (basetype))
{
if ((flags & LOOKUP_COMPLAIN) && basetype != error_mark_node)
error ("request for member `%D' in `%E', which is of non-aggregate type `%T'",
fns, instance, basetype);
return error_mark_node;
}
name = DECL_NAME (get_first_fn (fns));
if (IDENTIFIER_CTOR_OR_DTOR_P (name))
{
/* Callers should explicitly indicate whether they want to construct
the complete object or just the part without virtual bases. */
my_friendly_assert (name != ctor_identifier, 20000408);
/* Similarly for destructors. */
my_friendly_assert (name != dtor_identifier, 20000408);
if (name == complete_ctor_identifier
|| name == base_ctor_identifier)
pretty_name = constructor_name (basetype);
else
pretty_name = dtor_identifier;
}
else
pretty_name = name;
if (fns)
{
tree fn;
tree class_type = (conversion_path
? BINFO_TYPE (conversion_path)
: NULL_TREE);
mem_args = tree_cons (NULL_TREE, instance_ptr, args);
for (fn = fns; fn; fn = OVL_NEXT (fn))
{
tree t = OVL_CURRENT (fn);
tree this_arglist;
/* We can end up here for copy-init of same or base class. */
if ((flags & LOOKUP_ONLYCONVERTING)
&& DECL_NONCONVERTING_P (t))
continue;
if (DECL_NONSTATIC_MEMBER_FUNCTION_P (t))
this_arglist = mem_args;
else
this_arglist = args;
if (TREE_CODE (t) == TEMPLATE_DECL)
/* A member template. */
add_template_candidate (&candidates, t,
class_type,
explicit_targs,
this_arglist, optype,
access_binfo,
conversion_path,
flags,
DEDUCE_CALL);
else if (! template_only)
add_function_candidate (&candidates, t,
class_type,
this_arglist,
access_binfo,
conversion_path,
flags);
}
}
if (! any_viable (candidates))
{
/* XXX will LOOKUP_SPECULATIVELY be needed when this is done? */
if (flags & LOOKUP_SPECULATIVELY)
return NULL_TREE;
if (!COMPLETE_TYPE_P (basetype))
cxx_incomplete_type_error (instance_ptr, basetype);
else
error ("no matching function for call to `%T::%D(%A)%#V'",
basetype, pretty_name, user_args,
TREE_TYPE (TREE_TYPE (instance_ptr)));
print_z_candidates (candidates);
return error_mark_node;
}
candidates = splice_viable (candidates);
cand = tourney (candidates);
if (cand == 0)
{
error ("call of overloaded `%D(%A)' is ambiguous", pretty_name,
user_args);
print_z_candidates (candidates);
return error_mark_node;
}
if (DECL_PURE_VIRTUAL_P (cand->fn)
&& instance == current_class_ref
&& (DECL_CONSTRUCTOR_P (current_function_decl)
|| DECL_DESTRUCTOR_P (current_function_decl))
&& ! (flags & LOOKUP_NONVIRTUAL)
&& value_member (cand->fn, CLASSTYPE_PURE_VIRTUALS (basetype)))
error ((DECL_CONSTRUCTOR_P (current_function_decl) ?
"abstract virtual `%#D' called from constructor"
: "abstract virtual `%#D' called from destructor"),
cand->fn);
if (TREE_CODE (TREE_TYPE (cand->fn)) == METHOD_TYPE
&& is_dummy_object (instance_ptr))
{
error ("cannot call member function `%D' without object", cand->fn);
return error_mark_node;
}
if (DECL_VINDEX (cand->fn) && ! (flags & LOOKUP_NONVIRTUAL)
&& resolves_to_fixed_type_p (instance, 0))
flags |= LOOKUP_NONVIRTUAL;
if (TREE_CODE (TREE_TYPE (cand->fn)) == METHOD_TYPE)
call = build_over_call (cand, mem_args, flags);
else
{
call = build_over_call (cand, args, flags);
/* In an expression of the form `a->f()' where `f' turns out to
be a static member function, `a' is none-the-less evaluated. */
if (instance && TREE_SIDE_EFFECTS (instance))
call = build (COMPOUND_EXPR, TREE_TYPE (call), instance, call);
}
return call;
}
/* Returns nonzero iff standard conversion sequence ICS1 is a proper
subsequence of ICS2. */
static int
is_subseq (ics1, ics2)
tree ics1, ics2;
{
/* We can assume that a conversion of the same code
between the same types indicates a subsequence since we only get
here if the types we are converting from are the same. */
while (TREE_CODE (ics1) == RVALUE_CONV
|| TREE_CODE (ics1) == LVALUE_CONV)
ics1 = TREE_OPERAND (ics1, 0);
while (1)
{
while (TREE_CODE (ics2) == RVALUE_CONV
|| TREE_CODE (ics2) == LVALUE_CONV)
ics2 = TREE_OPERAND (ics2, 0);
if (TREE_CODE (ics2) == USER_CONV
|| TREE_CODE (ics2) == AMBIG_CONV
|| TREE_CODE (ics2) == IDENTITY_CONV)
/* At this point, ICS1 cannot be a proper subsequence of
ICS2. We can get a USER_CONV when we are comparing the
second standard conversion sequence of two user conversion
sequences. */
return 0;
ics2 = TREE_OPERAND (ics2, 0);
if (TREE_CODE (ics2) == TREE_CODE (ics1)
&& same_type_p (TREE_TYPE (ics2), TREE_TYPE (ics1))
&& same_type_p (TREE_TYPE (TREE_OPERAND (ics2, 0)),
TREE_TYPE (TREE_OPERAND (ics1, 0))))
return 1;
}
}
/* Returns nonzero iff DERIVED is derived from BASE. The inputs may
be any _TYPE nodes. */
int
is_properly_derived_from (derived, base)
tree derived;
tree base;
{
if (!IS_AGGR_TYPE_CODE (TREE_CODE (derived))
|| !IS_AGGR_TYPE_CODE (TREE_CODE (base)))
return 0;
/* We only allow proper derivation here. The DERIVED_FROM_P macro
considers every class derived from itself. */
return (!same_type_ignoring_top_level_qualifiers_p (derived, base)
&& DERIVED_FROM_P (base, derived));
}
/* We build the ICS for an implicit object parameter as a pointer
conversion sequence. However, such a sequence should be compared
as if it were a reference conversion sequence. If ICS is the
implicit conversion sequence for an implicit object parameter,
modify it accordingly. */
static void
maybe_handle_implicit_object (ics)
tree* ics;
{
if (ICS_THIS_FLAG (*ics))
{
/* [over.match.funcs]
For non-static member functions, the type of the
implicit object parameter is "reference to cv X"
where X is the class of which the function is a
member and cv is the cv-qualification on the member
function declaration. */
tree t = *ics;
tree reference_type;
/* The `this' parameter is a pointer to a class type. Make the
implict conversion talk about a reference to that same class
type. */
reference_type = TREE_TYPE (TREE_TYPE (*ics));
reference_type = build_reference_type (reference_type);
if (TREE_CODE (t) == QUAL_CONV)
t = TREE_OPERAND (t, 0);
if (TREE_CODE (t) == PTR_CONV)
t = TREE_OPERAND (t, 0);
t = build1 (IDENTITY_CONV, TREE_TYPE (TREE_TYPE (t)), NULL_TREE);
t = direct_reference_binding (reference_type, t);
*ics = t;
}
}
/* If *ICS is a REF_BIND set *ICS to the remainder of the conversion,
and return the type to which the reference refers. Otherwise,
leave *ICS unchanged and return NULL_TREE. */
static tree
maybe_handle_ref_bind (ics)
tree* ics;
{
if (TREE_CODE (*ics) == REF_BIND)
{
tree old_ics = *ics;
tree type = TREE_TYPE (TREE_TYPE (old_ics));
*ics = TREE_OPERAND (old_ics, 0);
ICS_USER_FLAG (*ics) = ICS_USER_FLAG (old_ics);
ICS_BAD_FLAG (*ics) = ICS_BAD_FLAG (old_ics);
return type;
}
return NULL_TREE;
}
/* Compare two implicit conversion sequences according to the rules set out in
[over.ics.rank]. Return values:
1: ics1 is better than ics2
-1: ics2 is better than ics1
0: ics1 and ics2 are indistinguishable */
static int
compare_ics (ics1, ics2)
tree ics1, ics2;
{
tree from_type1;
tree from_type2;
tree to_type1;
tree to_type2;
tree deref_from_type1 = NULL_TREE;
tree deref_from_type2 = NULL_TREE;
tree deref_to_type1 = NULL_TREE;
tree deref_to_type2 = NULL_TREE;
int rank1, rank2;
/* REF_BINDING is nonzero if the result of the conversion sequence
is a reference type. In that case TARGET_TYPE is the
type referred to by the reference. */
tree target_type1;
tree target_type2;
/* Handle implicit object parameters. */
maybe_handle_implicit_object (&ics1);
maybe_handle_implicit_object (&ics2);
/* Handle reference parameters. */
target_type1 = maybe_handle_ref_bind (&ics1);
target_type2 = maybe_handle_ref_bind (&ics2);
/* [over.ics.rank]
When comparing the basic forms of implicit conversion sequences (as
defined in _over.best.ics_)
--a standard conversion sequence (_over.ics.scs_) is a better
conversion sequence than a user-defined conversion sequence
or an ellipsis conversion sequence, and
--a user-defined conversion sequence (_over.ics.user_) is a
better conversion sequence than an ellipsis conversion sequence
(_over.ics.ellipsis_). */
rank1 = ICS_RANK (ics1);
rank2 = ICS_RANK (ics2);
if (rank1 > rank2)
return -1;
else if (rank1 < rank2)
return 1;
if (rank1 == BAD_RANK)
{
/* XXX Isn't this an extension? */
/* Both ICS are bad. We try to make a decision based on what
would have happenned if they'd been good. */
if (ICS_USER_FLAG (ics1) > ICS_USER_FLAG (ics2)
|| ICS_STD_RANK (ics1) > ICS_STD_RANK (ics2))
return -1;
else if (ICS_USER_FLAG (ics1) < ICS_USER_FLAG (ics2)
|| ICS_STD_RANK (ics1) < ICS_STD_RANK (ics2))
return 1;
/* We couldn't make up our minds; try to figure it out below. */
}
if (ICS_ELLIPSIS_FLAG (ics1))
/* Both conversions are ellipsis conversions. */
return 0;
/* User-defined conversion sequence U1 is a better conversion sequence
than another user-defined conversion sequence U2 if they contain the
same user-defined conversion operator or constructor and if the sec-
ond standard conversion sequence of U1 is better than the second
standard conversion sequence of U2. */
if (ICS_USER_FLAG (ics1))
{
tree t1, t2;
for (t1 = ics1; TREE_CODE (t1) != USER_CONV; t1 = TREE_OPERAND (t1, 0))
if (TREE_CODE (t1) == AMBIG_CONV)
return 0;
for (t2 = ics2; TREE_CODE (t2) != USER_CONV; t2 = TREE_OPERAND (t2, 0))
if (TREE_CODE (t2) == AMBIG_CONV)
return 0;
if (USER_CONV_FN (t1) != USER_CONV_FN (t2))
return 0;
/* We can just fall through here, after setting up
FROM_TYPE1 and FROM_TYPE2. */
from_type1 = TREE_TYPE (t1);
from_type2 = TREE_TYPE (t2);
}
else
{
/* We're dealing with two standard conversion sequences.
[over.ics.rank]
Standard conversion sequence S1 is a better conversion
sequence than standard conversion sequence S2 if
--S1 is a proper subsequence of S2 (comparing the conversion
sequences in the canonical form defined by _over.ics.scs_,
excluding any Lvalue Transformation; the identity
conversion sequence is considered to be a subsequence of
any non-identity conversion sequence */
from_type1 = ics1;
while (TREE_CODE (from_type1) != IDENTITY_CONV)
from_type1 = TREE_OPERAND (from_type1, 0);
from_type1 = TREE_TYPE (from_type1);
from_type2 = ics2;
while (TREE_CODE (from_type2) != IDENTITY_CONV)
from_type2 = TREE_OPERAND (from_type2, 0);
from_type2 = TREE_TYPE (from_type2);
}
if (same_type_p (from_type1, from_type2))
{
if (is_subseq (ics1, ics2))
return 1;
if (is_subseq (ics2, ics1))
return -1;
}
/* Otherwise, one sequence cannot be a subsequence of the other; they
don't start with the same type. This can happen when comparing the
second standard conversion sequence in two user-defined conversion
sequences. */
/* [over.ics.rank]
Or, if not that,
--the rank of S1 is better than the rank of S2 (by the rules
defined below):
Standard conversion sequences are ordered by their ranks: an Exact
Match is a better conversion than a Promotion, which is a better
conversion than a Conversion.
Two conversion sequences with the same rank are indistinguishable
unless one of the following rules applies:
--A conversion that is not a conversion of a pointer, or pointer
to member, to bool is better than another conversion that is such
a conversion.
The ICS_STD_RANK automatically handles the pointer-to-bool rule,
so that we do not have to check it explicitly. */
if (ICS_STD_RANK (ics1) < ICS_STD_RANK (ics2))
return 1;
else if (ICS_STD_RANK (ics2) < ICS_STD_RANK (ics1))
return -1;
to_type1 = TREE_TYPE (ics1);
to_type2 = TREE_TYPE (ics2);
if (TYPE_PTR_P (from_type1)
&& TYPE_PTR_P (from_type2)
&& TYPE_PTR_P (to_type1)
&& TYPE_PTR_P (to_type2))
{
deref_from_type1 = TREE_TYPE (from_type1);
deref_from_type2 = TREE_TYPE (from_type2);
deref_to_type1 = TREE_TYPE (to_type1);
deref_to_type2 = TREE_TYPE (to_type2);
}
/* The rules for pointers to members A::* are just like the rules
for pointers A*, except opposite: if B is derived from A then
A::* converts to B::*, not vice versa. For that reason, we
switch the from_ and to_ variables here. */
else if (TYPE_PTRMEM_P (from_type1)
&& TYPE_PTRMEM_P (from_type2)
&& TYPE_PTRMEM_P (to_type1)
&& TYPE_PTRMEM_P (to_type2))
{
deref_to_type1 = TYPE_OFFSET_BASETYPE (TREE_TYPE (from_type1));
deref_to_type2 = TYPE_OFFSET_BASETYPE (TREE_TYPE (from_type2));
deref_from_type1 = TYPE_OFFSET_BASETYPE (TREE_TYPE (to_type1));
deref_from_type2 = TYPE_OFFSET_BASETYPE (TREE_TYPE (to_type2));
}
else if (TYPE_PTRMEMFUNC_P (from_type1)
&& TYPE_PTRMEMFUNC_P (from_type2)
&& TYPE_PTRMEMFUNC_P (to_type1)
&& TYPE_PTRMEMFUNC_P (to_type2))
{
deref_to_type1 = TYPE_PTRMEMFUNC_OBJECT_TYPE (from_type1);
deref_to_type2 = TYPE_PTRMEMFUNC_OBJECT_TYPE (from_type2);
deref_from_type1 = TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type1);
deref_from_type2 = TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type2);
}
if (deref_from_type1 != NULL_TREE
&& IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type1))
&& IS_AGGR_TYPE_CODE (TREE_CODE (deref_from_type2)))
{
/* This was one of the pointer or pointer-like conversions.
[over.ics.rank]
--If class B is derived directly or indirectly from class A,
conversion of B* to A* is better than conversion of B* to
void*, and conversion of A* to void* is better than
conversion of B* to void*. */
if (TREE_CODE (deref_to_type1) == VOID_TYPE
&& TREE_CODE (deref_to_type2) == VOID_TYPE)
{
if (is_properly_derived_from (deref_from_type1,
deref_from_type2))
return -1;
else if (is_properly_derived_from (deref_from_type2,
deref_from_type1))
return 1;
}
else if (TREE_CODE (deref_to_type1) == VOID_TYPE
|| TREE_CODE (deref_to_type2) == VOID_TYPE)
{
if (same_type_p (deref_from_type1, deref_from_type2))
{
if (TREE_CODE (deref_to_type2) == VOID_TYPE)
{
if (is_properly_derived_from (deref_from_type1,
deref_to_type1))
return 1;
}
/* We know that DEREF_TO_TYPE1 is `void' here. */
else if (is_properly_derived_from (deref_from_type1,
deref_to_type2))
return -1;
}
}
else if (IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type1))
&& IS_AGGR_TYPE_CODE (TREE_CODE (deref_to_type2)))
{
/* [over.ics.rank]
--If class B is derived directly or indirectly from class A
and class C is derived directly or indirectly from B,
--conversion of C* to B* is better than conversion of C* to
A*,
--conversion of B* to A* is better than conversion of C* to
A* */
if (same_type_p (deref_from_type1, deref_from_type2))
{
if (is_properly_derived_from (deref_to_type1,
deref_to_type2))
return 1;
else if (is_properly_derived_from (deref_to_type2,
deref_to_type1))
return -1;
}
else if (same_type_p (deref_to_type1, deref_to_type2))
{
if (is_properly_derived_from (deref_from_type2,
deref_from_type1))
return 1;
else if (is_properly_derived_from (deref_from_type1,
deref_from_type2))
return -1;
}
}
}
else if (CLASS_TYPE_P (non_reference (from_type1))
&& same_type_p (from_type1, from_type2))
{
tree from = non_reference (from_type1);
/* [over.ics.rank]
--binding of an expression of type C to a reference of type
B& is better than binding an expression of type C to a
reference of type A&
--conversion of C to B is better than conversion of C to A, */
if (is_properly_derived_from (from, to_type1)
&& is_properly_derived_from (from, to_type2))
{
if (is_properly_derived_from (to_type1, to_type2))
return 1;
else if (is_properly_derived_from (to_type2, to_type1))
return -1;
}
}
else if (CLASS_TYPE_P (non_reference (to_type1))
&& same_type_p (to_type1, to_type2))
{
tree to = non_reference (to_type1);
/* [over.ics.rank]
--binding of an expression of type B to a reference of type
A& is better than binding an expression of type C to a
reference of type A&,
--onversion of B to A is better than conversion of C to A */
if (is_properly_derived_from (from_type1, to)
&& is_properly_derived_from (from_type2, to))
{
if (is_properly_derived_from (from_type2, from_type1))
return 1;
else if (is_properly_derived_from (from_type1, from_type2))
return -1;
}
}
/* [over.ics.rank]
--S1 and S2 differ only in their qualification conversion and yield
similar types T1 and T2 (_conv.qual_), respectively, and the cv-
qualification signature of type T1 is a proper subset of the cv-
qualification signature of type T2 */
if (TREE_CODE (ics1) == QUAL_CONV
&& TREE_CODE (ics2) == QUAL_CONV
&& same_type_p (from_type1, from_type2))
return comp_cv_qual_signature (to_type1, to_type2);
/* [over.ics.rank]
--S1 and S2 are reference bindings (_dcl.init.ref_), and the
types to which the references refer are the same type except for
top-level cv-qualifiers, and the type to which the reference
initialized by S2 refers is more cv-qualified than the type to
which the reference initialized by S1 refers */
if (target_type1 && target_type2
&& same_type_ignoring_top_level_qualifiers_p (to_type1, to_type2))
return comp_cv_qualification (target_type2, target_type1);
/* Neither conversion sequence is better than the other. */
return 0;
}
/* The source type for this standard conversion sequence. */
static tree
source_type (t)
tree t;
{
for (;; t = TREE_OPERAND (t, 0))
{
if (TREE_CODE (t) == USER_CONV
|| TREE_CODE (t) == AMBIG_CONV
|| TREE_CODE (t) == IDENTITY_CONV)
return TREE_TYPE (t);
}
abort ();
}
/* Note a warning about preferring WINNER to LOSER. We do this by storing
a pointer to LOSER and re-running joust to produce the warning if WINNER
is actually used. */
static void
add_warning (winner, loser)
struct z_candidate *winner, *loser;
{
winner->warnings = tree_cons (NULL_TREE,
build_zc_wrapper (loser),
winner->warnings);
}
/* Compare two candidates for overloading as described in
[over.match.best]. Return values:
1: cand1 is better than cand2
-1: cand2 is better than cand1
0: cand1 and cand2 are indistinguishable */
static int
joust (cand1, cand2, warn)
struct z_candidate *cand1, *cand2;
int warn;
{
int winner = 0;
int i, off1 = 0, off2 = 0, len;
/* Candidates that involve bad conversions are always worse than those
that don't. */
if (cand1->viable > cand2->viable)
return 1;
if (cand1->viable < cand2->viable)
return -1;
/* If we have two pseudo-candidates for conversions to the same type,
or two candidates for the same function, arbitrarily pick one. */
if (cand1->fn == cand2->fn
&& (TYPE_P (cand1->fn) || DECL_P (cand1->fn)))
return 1;
/* a viable function F1
is defined to be a better function than another viable function F2 if
for all arguments i, ICSi(F1) is not a worse conversion sequence than
ICSi(F2), and then */
/* for some argument j, ICSj(F1) is a better conversion sequence than
ICSj(F2) */
/* For comparing static and non-static member functions, we ignore
the implicit object parameter of the non-static function. The
standard says to pretend that the static function has an object
parm, but that won't work with operator overloading. */
len = TREE_VEC_LENGTH (cand1->convs);
if (len != TREE_VEC_LENGTH (cand2->convs))
{
if (DECL_STATIC_FUNCTION_P (cand1->fn)
&& ! DECL_STATIC_FUNCTION_P (cand2->fn))
off2 = 1;
else if (! DECL_STATIC_FUNCTION_P (cand1->fn)
&& DECL_STATIC_FUNCTION_P (cand2->fn))
{
off1 = 1;
--len;
}
else
abort ();
}
for (i = 0; i < len; ++i)
{
tree t1 = TREE_VEC_ELT (cand1->convs, i+off1);
tree t2 = TREE_VEC_ELT (cand2->convs, i+off2);
int comp = compare_ics (t1, t2);
if (comp != 0)
{
if (warn_sign_promo
&& ICS_RANK (t1) + ICS_RANK (t2) == STD_RANK + PROMO_RANK
&& TREE_CODE (t1) == STD_CONV
&& TREE_CODE (t2) == STD_CONV
&& TREE_CODE (TREE_TYPE (t1)) == INTEGER_TYPE
&& TREE_CODE (TREE_TYPE (t2)) == INTEGER_TYPE
&& (TYPE_PRECISION (TREE_TYPE (t1))
== TYPE_PRECISION (TREE_TYPE (t2)))
&& (TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (t1, 0)))
|| (TREE_CODE (TREE_TYPE (TREE_OPERAND (t1, 0)))
== ENUMERAL_TYPE)))
{
tree type = TREE_TYPE (TREE_OPERAND (t1, 0));
tree type1, type2;
struct z_candidate *w, *l;
if (comp > 0)
type1 = TREE_TYPE (t1), type2 = TREE_TYPE (t2),
w = cand1, l = cand2;
else
type1 = TREE_TYPE (t2), type2 = TREE_TYPE (t1),
w = cand2, l = cand1;
if (warn)
{
warning ("passing `%T' chooses `%T' over `%T'",
type, type1, type2);
warning (" in call to `%D'", w->fn);
}
else
add_warning (w, l);
}
if (winner && comp != winner)
{
winner = 0;
goto tweak;
}
winner = comp;
}
}
/* warn about confusing overload resolution for user-defined conversions,
either between a constructor and a conversion op, or between two
conversion ops. */
if (winner && cand1->second_conv
&& ((DECL_CONSTRUCTOR_P (cand1->fn)
!= DECL_CONSTRUCTOR_P (cand2->fn))
/* Don't warn if the two conv ops convert to the same type... */
|| (! DECL_CONSTRUCTOR_P (cand1->fn)
&& ! same_type_p (TREE_TYPE (TREE_TYPE (cand1->fn)),
TREE_TYPE (TREE_TYPE (cand2->fn))))))
{
int comp = compare_ics (cand1->second_conv, cand2->second_conv);
if (comp != winner)
{
struct z_candidate *w, *l;
tree convn;
if (winner == 1)
w = cand1, l = cand2;
else
w = cand2, l = cand1;
if (DECL_CONTEXT (cand1->fn) == DECL_CONTEXT (cand2->fn)
&& ! DECL_CONSTRUCTOR_P (cand1->fn)
&& ! DECL_CONSTRUCTOR_P (cand2->fn)
&& (convn = standard_conversion
(TREE_TYPE (TREE_TYPE (l->fn)),
TREE_TYPE (TREE_TYPE (w->fn)), NULL_TREE))
&& TREE_CODE (convn) == QUAL_CONV)
/* Don't complain about `operator char *()' beating
`operator const char *() const'. */;
else if (warn && warn_conversion)
{
tree source = source_type (TREE_VEC_ELT (w->convs, 0));
if (! DECL_CONSTRUCTOR_P (w->fn))
source = TREE_TYPE (source);
warning ("choosing `%D' over `%D'", w->fn, l->fn);
warning (" for conversion from `%T' to `%T'",
source, TREE_TYPE (w->second_conv));
warning (" because conversion sequence for the argument is better");
}
else
add_warning (w, l);
}
}
if (winner)
return winner;
/* or, if not that,
F1 is a non-template function and F2 is a template function
specialization. */
if (! cand1->template && cand2->template)
return 1;
else if (cand1->template && ! cand2->template)
return -1;
/* or, if not that,
F1 and F2 are template functions and the function template for F1 is
more specialized than the template for F2 according to the partial
ordering rules. */
if (cand1->template && cand2->template)
{
winner = more_specialized
(TI_TEMPLATE (cand1->template), TI_TEMPLATE (cand2->template),
DEDUCE_ORDER,
/* Tell the deduction code how many real function arguments
we saw, not counting the implicit 'this' argument. But,
add_function_candidate() suppresses the "this" argument
for constructors.
[temp.func.order]: The presence of unused ellipsis and default
arguments has no effect on the partial ordering of function
templates. */
TREE_VEC_LENGTH (cand1->convs)
- (DECL_NONSTATIC_MEMBER_FUNCTION_P (cand1->fn)
- DECL_CONSTRUCTOR_P (cand1->fn)));
/* HERE */
if (winner)
return winner;
}
/* or, if not that,
the context is an initialization by user-defined conversion (see
_dcl.init_ and _over.match.user_) and the standard conversion
sequence from the return type of F1 to the destination type (i.e.,
the type of the entity being initialized) is a better conversion
sequence than the standard conversion sequence from the return type
of F2 to the destination type. */
if (cand1->second_conv)
{
winner = compare_ics (cand1->second_conv, cand2->second_conv);
if (winner)
return winner;
}
/* Check whether we can discard a builtin candidate, either because we
have two identical ones or matching builtin and non-builtin candidates.
(Pedantically in the latter case the builtin which matched the user
function should not be added to the overload set, but we spot it here.
[over.match.oper]
... the builtin candidates include ...
- do not have the same parameter type list as any non-template
non-member candidate. */
if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE
|| TREE_CODE (cand2->fn) == IDENTIFIER_NODE)
{
for (i = 0; i < len; ++i)
if (!same_type_p (TREE_TYPE (TREE_VEC_ELT (cand1->convs, i)),
TREE_TYPE (TREE_VEC_ELT (cand2->convs, i))))
break;
if (i == TREE_VEC_LENGTH (cand1->convs))
{
if (cand1->fn == cand2->fn)
/* Two built-in candidates; arbitrarily pick one. */
return 1;
else if (TREE_CODE (cand1->fn) == IDENTIFIER_NODE)
/* cand1 is built-in; prefer cand2. */
return -1;
else
/* cand2 is built-in; prefer cand1. */
return 1;
}
}
/* If the two functions are the same (this can happen with declarations
in multiple scopes and arg-dependent lookup), arbitrarily choose one. */
if (DECL_P (cand1->fn) && DECL_P (cand2->fn)
&& equal_functions (cand1->fn, cand2->fn))
return 1;
tweak:
/* Extension: If the worst conversion for one candidate is worse than the
worst conversion for the other, take the first. */
if (!pedantic)
{
int rank1 = IDENTITY_RANK, rank2 = IDENTITY_RANK;
struct z_candidate *w = 0, *l = 0;
for (i = 0; i < len; ++i)
{
if (ICS_RANK (TREE_VEC_ELT (cand1->convs, i+off1)) > rank1)
rank1 = ICS_RANK (TREE_VEC_ELT (cand1->convs, i+off1));
if (ICS_RANK (TREE_VEC_ELT (cand2->convs, i+off2)) > rank2)
rank2 = ICS_RANK (TREE_VEC_ELT (cand2->convs, i+off2));
}
if (rank1 < rank2)
winner = 1, w = cand1, l = cand2;
if (rank1 > rank2)
winner = -1, w = cand2, l = cand1;
if (winner)
{
if (warn)
pedwarn ("ISO C++ says that `%D' and `%D' are ambiguous \
even though the worst conversion for the former is better than the worst \
conversion for the latter", w->fn, l->fn);
else
add_warning (w, l);
return winner;
}
}
my_friendly_assert (!winner, 20010121);
return 0;
}
/* Given a list of candidates for overloading, find the best one, if any.
This algorithm has a worst case of O(2n) (winner is last), and a best
case of O(n/2) (totally ambiguous); much better than a sorting
algorithm. */
static struct z_candidate *
tourney (candidates)
struct z_candidate *candidates;
{
struct z_candidate *champ = candidates, *challenger;
int fate;
int champ_compared_to_predecessor = 0;
/* Walk through the list once, comparing each current champ to the next
candidate, knocking out a candidate or two with each comparison. */
for (challenger = champ->next; challenger; )
{
fate = joust (champ, challenger, 0);
if (fate == 1)
challenger = challenger->next;
else
{
if (fate == 0)
{
champ = challenger->next;
if (champ == 0)
return 0;
champ_compared_to_predecessor = 0;
}
else
{
champ = challenger;
champ_compared_to_predecessor = 1;
}
challenger = champ->next;
}
}
/* Make sure the champ is better than all the candidates it hasn't yet
been compared to. */
for (challenger = candidates;
challenger != champ
&& !(champ_compared_to_predecessor && challenger->next == champ);
challenger = challenger->next)
{
fate = joust (champ, challenger, 0);
if (fate != 1)
return 0;
}
return champ;
}
/* Returns nonzero if things of type FROM can be converted to TO. */
int
can_convert (to, from)
tree to, from;
{
return can_convert_arg (to, from, NULL_TREE);
}
/* Returns nonzero if ARG (of type FROM) can be converted to TO. */
int
can_convert_arg (to, from, arg)
tree to, from, arg;
{
tree t = implicit_conversion (to, from, arg, LOOKUP_NORMAL);
return (t && ! ICS_BAD_FLAG (t));
}
/* Like can_convert_arg, but allows dubious conversions as well. */
int
can_convert_arg_bad (to, from, arg)
tree to, from, arg;
{
tree t = implicit_conversion (to, from, arg, LOOKUP_NORMAL);
return !!t;
}
/* Convert EXPR to TYPE. Return the converted expression.
Note that we allow bad conversions here because by the time we get to
this point we are committed to doing the conversion. If we end up
doing a bad conversion, convert_like will complain. */
tree
perform_implicit_conversion (type, expr)
tree type;
tree expr;
{
tree conv;
if (expr == error_mark_node)
return error_mark_node;
conv = implicit_conversion (type, TREE_TYPE (expr), expr,
LOOKUP_NORMAL);
if (!conv)
{
error ("could not convert `%E' to `%T'", expr, type);
return error_mark_node;
}
return convert_like (conv, expr);
}
/* Convert EXPR to TYPE (as a direct-initialization) if that is
permitted. If the conversion is valid, the converted expression is
returned. Otherwise, NULL_TREE is returned. */
tree
perform_direct_initialization_if_possible (tree type, tree expr)
{
tree conv;
if (type == error_mark_node || error_operand_p (expr))
return error_mark_node;
conv = implicit_conversion (type, TREE_TYPE (expr), expr,
LOOKUP_NORMAL);
if (!conv || ICS_BAD_FLAG (conv))
return NULL_TREE;
return convert_like_real (conv, expr, NULL_TREE, 0, 0,
/*issue_conversion_warnings=*/false);
}
/* DECL is a VAR_DECL whose type is a REFERENCE_TYPE. The reference
is being bound to a temporary. Create and return a new VAR_DECL
with the indicated TYPE; this variable will store the value to
which the reference is bound. */
tree
make_temporary_var_for_ref_to_temp (tree decl, tree type)
{
tree var;
/* Create the variable. */
var = build_decl (VAR_DECL, NULL_TREE, type);
DECL_ARTIFICIAL (var) = 1;
TREE_USED (var) = 1;
/* Register the variable. */
if (TREE_STATIC (decl))
{
/* Namespace-scope or local static; give it a mangled name. */
tree name;
TREE_STATIC (var) = 1;
name = mangle_ref_init_variable (decl);
DECL_NAME (var) = name;
SET_DECL_ASSEMBLER_NAME (var, name);
var = pushdecl_top_level (var);
}
else
{
/* Create a new cleanup level if necessary. */
maybe_push_cleanup_level (type);
/* Don't push unnamed temps. Do set DECL_CONTEXT, though. */
DECL_CONTEXT (var) = current_function_decl;
}
return var;
}
/* Convert EXPR to the indicated reference TYPE, in a way suitable for
initializing a variable of that TYPE. If DECL is non-NULL, it is
the VAR_DECL being initialized with the EXPR. (In that case, the
type of DECL will be TYPE.)
Return the converted expression. */
tree
initialize_reference (type, expr, decl)
tree type;
tree expr;
tree decl;
{
tree conv;
if (type == error_mark_node || error_operand_p (expr))
return error_mark_node;
conv = reference_binding (type, TREE_TYPE (expr), expr, LOOKUP_NORMAL);
if (!conv || ICS_BAD_FLAG (conv))
{
error ("could not convert `%E' to `%T'", expr, type);
return error_mark_node;
}
/* If DECL is non-NULL, then this special rule applies:
[class.temporary]
The temporary to which the reference is bound or the temporary
that is the complete object to which the reference is bound
persists for the lifetime of the reference.
The temporaries created during the evaluation of the expression
initializing the reference, except the temporary to which the
reference is bound, are destroyed at the end of the
full-expression in which they are created.
In that case, we store the converted expression into a new
VAR_DECL in a new scope.
However, we want to be careful not to create temporaries when
they are not required. For example, given:
struct B {};
struct D : public B {};
D f();
const B& b = f();
there is no need to copy the return value from "f"; we can just
extend its lifetime. Similarly, given:
struct S {};
struct T { operator S(); };
T t;
const S& s = t;
we can extend the lifetime of the return value of the conversion
operator. */
my_friendly_assert (TREE_CODE (conv) == REF_BIND, 20030302);
if (decl)
{
tree var;
tree base_conv_type;
/* Skip over the REF_BIND. */
conv = TREE_OPERAND (conv, 0);
/* If the next conversion is a BASE_CONV, skip that too -- but
remember that the conversion was required. */
if (TREE_CODE (conv) == BASE_CONV && !NEED_TEMPORARY_P (conv))
{
base_conv_type = TREE_TYPE (conv);
conv = TREE_OPERAND (conv, 0);
}
else
base_conv_type = NULL_TREE;
/* Perform the remainder of the conversion. */
expr = convert_like (conv, expr);
if (!real_non_cast_lvalue_p (expr))
{
tree init;
tree type;
/* Create the temporary variable. */
type = TREE_TYPE (expr);
var = make_temporary_var_for_ref_to_temp (decl, type);
layout_decl (var, 0);
if (at_function_scope_p ())
{
tree cleanup;
add_decl_stmt (var);
cleanup = cxx_maybe_build_cleanup (var);
if (cleanup)
finish_decl_cleanup (var, cleanup);
}
else
{
rest_of_decl_compilation (var, NULL, /*toplev=*/1, at_eof);
if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
static_aggregates = tree_cons (NULL_TREE, var,
static_aggregates);
}
init = build (INIT_EXPR, type, var, expr);
/* Use its address to initialize the reference variable. */
expr = build_address (var);
expr = build (COMPOUND_EXPR, TREE_TYPE (expr), init, expr);
}
else
/* Take the address of EXPR. */
expr = build_unary_op (ADDR_EXPR, expr, 0);
/* If a BASE_CONV was required, perform it now. */
if (base_conv_type)
expr = (perform_implicit_conversion
(build_pointer_type (base_conv_type), expr));
return build_nop (type, expr);
}
/* Perform the conversion. */
return convert_like (conv, expr);
}
#include "gt-cp-call.h"
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