tree
lambda_return_type (tree expr)
{
if (expr == NULL_TREE)
return void_type_node;
if (type_unknown_p (expr)
|| BRACE_ENCLOSED_INITIALIZER_P (expr))
{
cxx_incomplete_type_error (expr, TREE_TYPE (expr));
return void_type_node;
}
gcc_checking_assert (!type_dependent_expression_p (expr));
return cv_unqualified (type_decays_to (unlowered_expr_type (expr)));
}
tree
build_throw (tree exp)
{
if (exp == error_mark_node)
return exp;
if (processing_template_decl)
{
if (cfun)
current_function_returns_abnormally = 1;
exp = build_min (THROW_EXPR, void_type_node, exp);
SET_EXPR_LOCATION (exp, input_location);
return exp;
}
if (exp && null_node_p (exp))
warning (0, "throwing NULL, which has integral, not pointer type");
if (exp != NULL_TREE)
{
if (!is_admissible_throw_operand_or_catch_parameter (exp, true))
return error_mark_node;
}
if (! doing_eh ())
return error_mark_node;
if (exp)
{
tree throw_type;
tree temp_type;
tree cleanup;
tree object, ptr;
tree tmp;
tree allocate_expr;
/* The CLEANUP_TYPE is the internal type of a destructor. */
if (!cleanup_type)
{
tmp = build_function_type_list (void_type_node,
ptr_type_node, NULL_TREE);
cleanup_type = build_pointer_type (tmp);
}
if (!throw_fn)
{
tree name = get_identifier ("__cxa_throw");
throw_fn = get_global_binding (name);
if (!throw_fn)
{
/* Declare void __cxa_throw (void*, void*, void (*)(void*)). */
/* ??? Second argument is supposed to be "std::type_info*". */
tmp = build_function_type_list (void_type_node,
ptr_type_node, ptr_type_node,
cleanup_type, NULL_TREE);
throw_fn = push_throw_library_fn (name, tmp);
if (flag_tm)
{
tree itm_name = get_identifier ("_ITM_cxa_throw");
tree itm_fn = get_global_binding (itm_name);
if (!itm_fn)
itm_fn = push_throw_library_fn (itm_name, tmp);
apply_tm_attr (itm_fn, get_identifier ("transaction_pure"));
record_tm_replacement (throw_fn, itm_fn);
}
}
}
/* [except.throw]
A throw-expression initializes a temporary object, the type
of which is determined by removing any top-level
cv-qualifiers from the static type of the operand of throw
and adjusting the type from "array of T" or "function return
T" to "pointer to T" or "pointer to function returning T"
respectively. */
temp_type = is_bitfield_expr_with_lowered_type (exp);
if (!temp_type)
temp_type = cv_unqualified (type_decays_to (TREE_TYPE (exp)));
/* OK, this is kind of wacky. The standard says that we call
terminate when the exception handling mechanism, after
completing evaluation of the expression to be thrown but
before the exception is caught (_except.throw_), calls a
user function that exits via an uncaught exception.
So we have to protect the actual initialization of the
exception object with terminate(), but evaluate the
expression first. Since there could be temps in the
expression, we need to handle that, too. We also expand
the call to __cxa_allocate_exception first (which doesn't
matter, since it can't throw). */
/* Allocate the space for the exception. */
allocate_expr = do_allocate_exception (temp_type);
allocate_expr = get_target_expr (allocate_expr);
ptr = TARGET_EXPR_SLOT (allocate_expr);
TARGET_EXPR_CLEANUP (allocate_expr) = do_free_exception (ptr);
CLEANUP_EH_ONLY (allocate_expr) = 1;
object = build_nop (build_pointer_type (temp_type), ptr);
object = cp_build_fold_indirect_ref (object);
/* And initialize the exception object. */
if (CLASS_TYPE_P (temp_type))
{
int flags = LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING;
vec<tree, va_gc> *exp_vec;
bool converted = false;
/* Under C++0x [12.8/16 class.copy], a thrown lvalue is sometimes
treated as an rvalue for the purposes of overload resolution
to favor move constructors over copy constructors. */
if (/* Must be a local, automatic variable. */
VAR_P (exp)
&& DECL_CONTEXT (exp) == current_function_decl
&& ! TREE_STATIC (exp)
/* The variable must not have the `volatile' qualifier. */
&& !(cp_type_quals (TREE_TYPE (exp)) & TYPE_QUAL_VOLATILE))
{
tree moved = move (exp);
exp_vec = make_tree_vector_single (moved);
moved = (build_special_member_call
(object, complete_ctor_identifier, &exp_vec,
TREE_TYPE (object), flags|LOOKUP_PREFER_RVALUE,
tf_none));
release_tree_vector (exp_vec);
if (moved != error_mark_node)
{
exp = moved;
converted = true;
}
}
/* Call the copy constructor. */
if (!converted)
{
exp_vec = make_tree_vector_single (exp);
exp = (build_special_member_call
(object, complete_ctor_identifier, &exp_vec,
TREE_TYPE (object), flags, tf_warning_or_error));
release_tree_vector (exp_vec);
}
if (exp == error_mark_node)
{
error (" in thrown expression");
return error_mark_node;
}
}
else
{
tmp = decay_conversion (exp, tf_warning_or_error);
if (tmp == error_mark_node)
return error_mark_node;
exp = build2 (INIT_EXPR, temp_type, object, tmp);
}
/* Mark any cleanups from the initialization as MUST_NOT_THROW, since
they are run after the exception object is initialized. */
cp_walk_tree_without_duplicates (&exp, wrap_cleanups_r, 0);
/* Prepend the allocation. */
exp = build2 (COMPOUND_EXPR, TREE_TYPE (exp), allocate_expr, exp);
/* Force all the cleanups to be evaluated here so that we don't have
to do them during unwinding. */
exp = build1 (CLEANUP_POINT_EXPR, void_type_node, exp);
throw_type = build_eh_type_type (prepare_eh_type (TREE_TYPE (object)));
cleanup = NULL_TREE;
if (type_build_dtor_call (TREE_TYPE (object)))
{
tree dtor_fn = lookup_fnfields (TYPE_BINFO (TREE_TYPE (object)),
complete_dtor_identifier, 0);
dtor_fn = BASELINK_FUNCTIONS (dtor_fn);
mark_used (dtor_fn);
if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (object)))
{
cxx_mark_addressable (dtor_fn);
/* Pretend it's a normal function. */
cleanup = build1 (ADDR_EXPR, cleanup_type, dtor_fn);
}
}
if (cleanup == NULL_TREE)
cleanup = build_int_cst (cleanup_type, 0);
/* ??? Indicate that this function call throws throw_type. */
tmp = cp_build_function_call_nary (throw_fn, tf_warning_or_error,
ptr, throw_type, cleanup, NULL_TREE);
/* Tack on the initialization stuff. */
exp = build2 (COMPOUND_EXPR, TREE_TYPE (tmp), exp, tmp);
}
else
{
/* Rethrow current exception. */
if (!rethrow_fn)
{
tree name = get_identifier ("__cxa_rethrow");
rethrow_fn = get_global_binding (name);
if (!rethrow_fn)
/* Declare void __cxa_rethrow (void). */
rethrow_fn = push_throw_library_fn
(name, build_function_type_list (void_type_node, NULL_TREE));
if (flag_tm)
apply_tm_attr (rethrow_fn, get_identifier ("transaction_pure"));
}
/* ??? Indicate that this function call allows exceptions of the type
of the enclosing catch block (if known). */
exp = cp_build_function_call_vec (rethrow_fn, NULL, tf_warning_or_error);
}
exp = build1 (THROW_EXPR, void_type_node, exp);
SET_EXPR_LOCATION (exp, input_location);
return exp;
}
void
make_friend_class (tree type, tree friend_type, bool complain)
{
tree classes;
/* CLASS_TEMPLATE_DEPTH counts the number of template headers for
the enclosing class. FRIEND_DEPTH counts the number of template
headers used for this friend declaration. TEMPLATE_MEMBER_P,
defined inside the `if' block for TYPENAME_TYPE case, is true if
a template header in FRIEND_DEPTH is intended for DECLARATOR.
For example, the code
template <class T> struct A {
template <class U> struct B {
template <class V> template <class W>
friend class C<V>::D;
};
};
will eventually give the following results
1. CLASS_TEMPLATE_DEPTH equals 2 (for `T' and `U').
2. FRIEND_DEPTH equals 2 (for `V' and `W').
3. TEMPLATE_MEMBER_P is true (for `W').
The friend is a template friend iff FRIEND_DEPTH is nonzero. */
int class_template_depth = template_class_depth (type);
int friend_depth = processing_template_decl - class_template_depth;
if (! MAYBE_CLASS_TYPE_P (friend_type))
{
/* N1791: If the type specifier in a friend declaration designates a
(possibly cv-qualified) class type, that class is declared as a
friend; otherwise, the friend declaration is ignored.
So don't complain in C++0x mode. */
if (cxx_dialect < cxx0x)
pedwarn (input_location, complain ? 0 : OPT_pedantic,
"invalid type %qT declared %<friend%>", friend_type);
return;
}
friend_type = cv_unqualified (friend_type);
if (check_for_bare_parameter_packs (friend_type))
return;
if (friend_depth)
/* If the TYPE is a template then it makes sense for it to be
friends with itself; this means that each instantiation is
friends with all other instantiations. */
{
if (CLASS_TYPE_P (friend_type)
&& CLASSTYPE_TEMPLATE_SPECIALIZATION (friend_type)
&& uses_template_parms (friend_type))
{
/* [temp.friend]
Friend declarations shall not declare partial
specializations. */
error ("partial specialization %qT declared %<friend%>",
friend_type);
return;
}
}
else if (same_type_p (type, friend_type))
{
if (complain)
warning (0, "class %qT is implicitly friends with itself",
type);
return;
}
/* [temp.friend]
A friend of a class or class template can be a function or
class template, a specialization of a function template or
class template, or an ordinary (nontemplate) function or
class. */
if (!friend_depth)
;/* ok */
else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
{
if (TREE_CODE (TYPENAME_TYPE_FULLNAME (friend_type))
== TEMPLATE_ID_EXPR)
{
/* template <class U> friend class T::X<U>; */
/* [temp.friend]
Friend declarations shall not declare partial
specializations. */
error ("partial specialization %qT declared %<friend%>",
friend_type);
return;
}
else
{
/* We will figure this out later. */
bool template_member_p = false;
tree ctype = TYPE_CONTEXT (friend_type);
tree name = TYPE_IDENTIFIER (friend_type);
tree decl;
if (!uses_template_parms_level (ctype, class_template_depth
+ friend_depth))
template_member_p = true;
if (class_template_depth)
{
/* We rely on tsubst_friend_class to check the
validity of the declaration later. */
if (template_member_p)
friend_type
= make_unbound_class_template (ctype,
name,
current_template_parms,
tf_error);
else
friend_type
= make_typename_type (ctype, name, class_type, tf_error);
}
else
{
decl = lookup_member (ctype, name, 0, true, tf_warning_or_error);
if (!decl)
{
error ("%qT is not a member of %qT", name, ctype);
return;
}
if (template_member_p && !DECL_CLASS_TEMPLATE_P (decl))
{
error ("%qT is not a member class template of %qT",
name, ctype);
error ("%q+D declared here", decl);
return;
}
if (!template_member_p && (TREE_CODE (decl) != TYPE_DECL
|| !CLASS_TYPE_P (TREE_TYPE (decl))))
{
error ("%qT is not a nested class of %qT",
name, ctype);
error ("%q+D declared here", decl);
return;
}
friend_type = CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl));
}
}
}
else if (TREE_CODE (friend_type) == TEMPLATE_TYPE_PARM)
{
/* template <class T> friend class T; */
error ("template parameter type %qT declared %<friend%>", friend_type);
return;
}
else if (!CLASSTYPE_TEMPLATE_INFO (friend_type))
{
/* template <class T> friend class A; where A is not a template */
error ("%q#T is not a template", friend_type);
return;
}
else
/* template <class T> friend class A; where A is a template */
friend_type = CLASSTYPE_TI_TEMPLATE (friend_type);
if (friend_type == error_mark_node)
return;
/* See if it is already a friend. */
for (classes = CLASSTYPE_FRIEND_CLASSES (type);
classes;
classes = TREE_CHAIN (classes))
{
tree probe = TREE_VALUE (classes);
if (TREE_CODE (friend_type) == TEMPLATE_DECL)
{
if (friend_type == probe)
{
if (complain)
warning (0, "%qD is already a friend of %qT", probe, type);
break;
}
}
else if (TREE_CODE (probe) != TEMPLATE_DECL)
{
if (same_type_p (probe, friend_type))
{
if (complain)
warning (0, "%qT is already a friend of %qT", probe, type);
break;
}
}
}
if (!classes)
{
maybe_add_class_template_decl_list (type, friend_type, /*friend_p=*/1);
CLASSTYPE_FRIEND_CLASSES (type)
= tree_cons (NULL_TREE, friend_type, CLASSTYPE_FRIEND_CLASSES (type));
if (TREE_CODE (friend_type) == TEMPLATE_DECL)
friend_type = TREE_TYPE (friend_type);
if (!uses_template_parms (type))
CLASSTYPE_BEFRIENDING_CLASSES (friend_type)
= tree_cons (NULL_TREE, type,
CLASSTYPE_BEFRIENDING_CLASSES (friend_type));
}
}
