static tree
cp_ubsan_dfs_initialize_vtbl_ptrs (tree binfo, void *data)
{
if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
return dfs_skip_bases;
if (!BINFO_PRIMARY_P (binfo) || BINFO_VIRTUAL_P (binfo))
{
tree base_ptr = TREE_VALUE ((tree) data);
base_ptr = build_base_path (PLUS_EXPR, base_ptr, binfo, /*nonnull=*/1,
tf_warning_or_error);
/* Compute the location of the vtpr. */
tree vtbl_ptr
= build_vfield_ref (cp_build_indirect_ref (base_ptr, RO_NULL,
tf_warning_or_error),
TREE_TYPE (binfo));
gcc_assert (vtbl_ptr != error_mark_node);
/* Assign NULL to the vptr. */
tree vtbl = build_zero_cst (TREE_TYPE (vtbl_ptr));
finish_expr_stmt (cp_build_modify_expr (vtbl_ptr, NOP_EXPR, vtbl,
tf_warning_or_error));
}
return NULL_TREE;
}
tree
build_throw (tree exp)
{
tree fn;
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)
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 && decl_is_java_type (TREE_TYPE (exp), 1))
{
tree fn = get_identifier ("_Jv_Throw");
if (!get_global_value_if_present (fn, &fn))
{
/* Declare void _Jv_Throw (void *). */
tree tmp;
tmp = build_function_type_list (ptr_type_node,
ptr_type_node, NULL_TREE);
fn = push_throw_library_fn (fn, tmp);
}
else if (really_overloaded_fn (fn))
{
error ("%qD should never be overloaded", fn);
return error_mark_node;
}
fn = OVL_CURRENT (fn);
exp = cp_build_function_call_nary (fn, tf_warning_or_error,
exp, NULL_TREE);
}
else 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);
}
fn = get_identifier ("__cxa_throw");
if (!get_global_value_if_present (fn, &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);
fn = push_throw_library_fn (fn, tmp);
if (flag_tm)
{
tree fn2 = get_identifier ("_ITM_cxa_throw");
if (!get_global_value_if_present (fn2, &fn2))
fn2 = push_throw_library_fn (fn2, tmp);
apply_tm_attr (fn2, get_identifier ("transaction_pure"));
record_tm_replacement (fn, fn2);
}
}
/* [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_indirect_ref (object, RO_NULL, tf_warning_or_error);
/* And initialize the exception object. */
if (CLASS_TYPE_P (temp_type))
{
int flags = LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING;
vec<tree, va_gc> *exp_vec;
/* 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))
flags = flags | LOOKUP_PREFER_RVALUE;
/* Call the copy constructor. */
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 fn = lookup_fnfields (TYPE_BINFO (TREE_TYPE (object)),
complete_dtor_identifier, 0);
fn = BASELINK_FUNCTIONS (fn);
mark_used (fn);
if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (object)))
{
cxx_mark_addressable (fn);
/* Pretend it's a normal function. */
cleanup = build1 (ADDR_EXPR, cleanup_type, 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 (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. */
tree fn = get_identifier ("__cxa_rethrow");
if (!get_global_value_if_present (fn, &fn))
{
/* Declare void __cxa_rethrow (void). */
fn = push_throw_library_fn
(fn, build_function_type_list (void_type_node, NULL_TREE));
}
if (flag_tm)
apply_tm_attr (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 (fn, NULL, tf_warning_or_error);
}
exp = build1 (THROW_EXPR, void_type_node, exp);
SET_EXPR_LOCATION (exp, input_location);
return exp;
}
tree
expand_start_catch_block (tree decl)
{
tree exp;
tree type, init;
if (! doing_eh ())
return NULL_TREE;
if (decl)
{
if (!is_admissible_throw_operand_or_catch_parameter (decl, false))
decl = error_mark_node;
type = prepare_eh_type (TREE_TYPE (decl));
mark_used (eh_type_info (type));
}
else
type = NULL_TREE;
if (decl && decl_is_java_type (type, 1))
{
/* Java only passes object via pointer and doesn't require
adjusting. The java object is immediately before the
generic exception header. */
exp = build_exc_ptr ();
exp = build1 (NOP_EXPR, build_pointer_type (type), exp);
exp = fold_build_pointer_plus (exp,
fold_build1_loc (input_location,
NEGATE_EXPR, sizetype,
TYPE_SIZE_UNIT (TREE_TYPE (exp))));
exp = cp_build_indirect_ref (exp, RO_NULL, tf_warning_or_error);
initialize_handler_parm (decl, exp);
return type;
}
/* Call __cxa_end_catch at the end of processing the exception. */
push_eh_cleanup (type);
init = do_begin_catch ();
/* If there's no decl at all, then all we need to do is make sure
to tell the runtime that we've begun handling the exception. */
if (decl == NULL || decl == error_mark_node || init == error_mark_node)
finish_expr_stmt (init);
/* If the C++ object needs constructing, we need to do that before
calling __cxa_begin_catch, so that std::uncaught_exception gets
the right value during the copy constructor. */
else if (flag_use_cxa_get_exception_ptr
&& TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (decl)))
{
exp = do_get_exception_ptr ();
initialize_handler_parm (decl, exp);
finish_expr_stmt (init);
}
/* Otherwise the type uses a bitwise copy, and we don't have to worry
about the value of std::uncaught_exception and therefore can do the
copy with the return value of __cxa_end_catch instead. */
else
{
tree init_type = type;
/* Pointers are passed by values, everything else by reference. */
if (!TYPE_PTR_P (type))
init_type = build_pointer_type (type);
if (init_type != TREE_TYPE (init))
init = build1 (NOP_EXPR, init_type, init);
exp = create_temporary_var (init_type);
DECL_REGISTER (exp) = 1;
cp_finish_decl (exp, init, /*init_const_expr=*/false,
NULL_TREE, LOOKUP_ONLYCONVERTING);
initialize_handler_parm (decl, exp);
}
return type;
}
