static tree
build_up_reference (tree type, tree arg, int flags, tree decl)
{
tree rval;
tree argtype = TREE_TYPE (arg);
tree target_type = TREE_TYPE (type);
gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
if ((flags & DIRECT_BIND) && ! real_lvalue_p (arg))
{
/* Create a new temporary variable. We can't just use a TARGET_EXPR
here because it needs to live as long as DECL. */
tree targ = arg;
arg = make_temporary_var_for_ref_to_temp (decl, TREE_TYPE (arg));
/* Process the initializer for the declaration. */
DECL_INITIAL (arg) = targ;
cp_finish_decl (arg, targ, /*init_const_expr_p=*/false, NULL_TREE,
LOOKUP_ONLYCONVERTING|DIRECT_BIND);
}
else if (!(flags & DIRECT_BIND) && ! lvalue_p (arg))
return get_target_expr (arg);
/* If we had a way to wrap this up, and say, if we ever needed its
address, transform all occurrences of the register, into a memory
reference we could win better. */
rval = cp_build_unary_op (ADDR_EXPR, arg, 1, tf_warning_or_error);
if (rval == error_mark_node)
return error_mark_node;
if ((flags & LOOKUP_PROTECT)
&& TYPE_MAIN_VARIANT (argtype) != TYPE_MAIN_VARIANT (target_type)
&& MAYBE_CLASS_TYPE_P (argtype)
&& MAYBE_CLASS_TYPE_P (target_type))
{
/* We go through lookup_base for the access control. */
tree binfo = lookup_base (argtype, target_type, ba_check, NULL);
if (binfo == error_mark_node)
return error_mark_node;
if (binfo == NULL_TREE)
return error_not_base_type (target_type, argtype);
rval = build_base_path (PLUS_EXPR, rval, binfo, 1);
}
else
rval
= convert_to_pointer_force (build_pointer_type (target_type), rval);
return build_nop (type, rval);
}
static void
initialize_handler_parm (tree decl, tree exp)
{
tree init;
tree init_type;
/* Make sure we mark the catch param as used, otherwise we'll get a
warning about an unused ((anonymous)). */
TREE_USED (decl) = 1;
/* Figure out the type that the initializer is. Pointers are returned
adjusted by value from __cxa_begin_catch. Others are returned by
reference. */
init_type = TREE_TYPE (decl);
if (!POINTER_TYPE_P (init_type))
init_type = build_reference_type (init_type);
choose_personality_routine (decl_is_java_type (init_type, 0)
? lang_java : lang_cplusplus);
/* Since pointers are passed by value, initialize a reference to
pointer catch parm with the address of the temporary. */
if (TREE_CODE (init_type) == REFERENCE_TYPE
&& TYPE_PTR_P (TREE_TYPE (init_type)))
exp = cp_build_unary_op (ADDR_EXPR, exp, 1, tf_warning_or_error);
exp = ocp_convert (init_type, exp, CONV_IMPLICIT|CONV_FORCE_TEMP, 0);
init = convert_from_reference (exp);
/* If the constructor for the catch parm exits via an exception, we
must call terminate. See eh23.C. */
if (TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (decl)))
{
/* Generate the copy constructor call directly so we can wrap it.
See also expand_default_init. */
init = ocp_convert (TREE_TYPE (decl), init,
CONV_IMPLICIT|CONV_FORCE_TEMP, 0);
/* Force cleanups now to avoid nesting problems with the
MUST_NOT_THROW_EXPR. */
init = fold_build_cleanup_point_expr (TREE_TYPE (init), init);
init = build1 (MUST_NOT_THROW_EXPR, TREE_TYPE (init), init);
}
decl = pushdecl (decl);
start_decl_1 (decl, true);
cp_finish_decl (decl, init, /*init_const_expr_p=*/false, NULL_TREE,
LOOKUP_ONLYCONVERTING|DIRECT_BIND);
}
tree
convert_to_reference (tree reftype, tree expr, int convtype,
int flags, tree decl)
{
tree type = TYPE_MAIN_VARIANT (TREE_TYPE (reftype));
tree intype;
tree rval = NULL_TREE;
tree rval_as_conversion = NULL_TREE;
bool can_convert_intype_to_type;
if (TREE_CODE (type) == FUNCTION_TYPE
&& TREE_TYPE (expr) == unknown_type_node)
expr = instantiate_type (type, expr,
(flags & LOOKUP_COMPLAIN)
? tf_warning_or_error : tf_none);
if (expr == error_mark_node)
return error_mark_node;
intype = TREE_TYPE (expr);
gcc_assert (TREE_CODE (intype) != REFERENCE_TYPE);
gcc_assert (TREE_CODE (reftype) == REFERENCE_TYPE);
intype = TYPE_MAIN_VARIANT (intype);
can_convert_intype_to_type = can_convert (type, intype);
if (!can_convert_intype_to_type
&& (convtype & CONV_IMPLICIT) && MAYBE_CLASS_TYPE_P (intype)
&& ! (flags & LOOKUP_NO_CONVERSION))
{
/* Look for a user-defined conversion to lvalue that we can use. */
rval_as_conversion
= build_type_conversion (reftype, expr);
if (rval_as_conversion && rval_as_conversion != error_mark_node
&& real_lvalue_p (rval_as_conversion))
{
expr = rval_as_conversion;
rval_as_conversion = NULL_TREE;
intype = type;
can_convert_intype_to_type = 1;
}
}
if (((convtype & CONV_STATIC) && can_convert (intype, type))
|| ((convtype & CONV_IMPLICIT) && can_convert_intype_to_type))
{
if (flags & LOOKUP_COMPLAIN)
{
tree ttl = TREE_TYPE (reftype);
tree ttr = lvalue_type (expr);
if (! real_lvalue_p (expr))
warn_ref_binding (reftype, intype, decl);
if (! (convtype & CONV_CONST)
&& !at_least_as_qualified_p (ttl, ttr))
permerror (input_location, "conversion from %qT to %qT discards qualifiers",
ttr, reftype);
}
return build_up_reference (reftype, expr, flags, decl);
}
else if ((convtype & CONV_REINTERPRET) && lvalue_p (expr))
{
/* When casting an lvalue to a reference type, just convert into
a pointer to the new type and deference it. This is allowed
by San Diego WP section 5.2.9 paragraph 12, though perhaps it
should be done directly (jason). (int &)ri ---> *(int*)&ri */
/* B* bp; A& ar = (A&)bp; is valid, but it's probably not what they
meant. */
if (TREE_CODE (intype) == POINTER_TYPE
&& (comptypes (TREE_TYPE (intype), type,
COMPARE_BASE | COMPARE_DERIVED)))
warning (0, "casting %qT to %qT does not dereference pointer",
intype, reftype);
rval = cp_build_unary_op (ADDR_EXPR, expr, 0, tf_warning_or_error);
if (rval != error_mark_node)
rval = convert_force (build_pointer_type (TREE_TYPE (reftype)),
rval, 0);
if (rval != error_mark_node)
rval = build1 (NOP_EXPR, reftype, rval);
}
else
{
rval = convert_for_initialization (NULL_TREE, type, expr, flags,
"converting", 0, 0,
tf_warning_or_error);
if (rval == NULL_TREE || rval == error_mark_node)
return rval;
warn_ref_binding (reftype, intype, decl);
rval = build_up_reference (reftype, rval, flags, decl);
}
if (rval)
{
/* If we found a way to convert earlier, then use it. */
return rval;
}
if (flags & LOOKUP_COMPLAIN)
error ("cannot convert type %qT to type %qT", intype, reftype);
return error_mark_node;
}
