static bool
is_admissible_throw_operand_or_catch_parameter (tree t, bool is_throw)
{
tree expr = is_throw ? t : NULL_TREE;
tree type = TREE_TYPE (t);
/* C++11 [except.handle] The exception-declaration shall not denote
an incomplete type, an abstract class type, or an rvalue reference
type. */
/* 15.1/4 [...] The type of the throw-expression shall not be an
incomplete type, or a pointer or a reference to an incomplete
type, other than void*, const void*, volatile void*, or
const volatile void*. Except for these restriction and the
restrictions on type matching mentioned in 15.3, the operand
of throw is treated exactly as a function argument in a call
(5.2.2) or the operand of a return statement. */
if (!complete_ptr_ref_or_void_ptr_p (type, expr))
return false;
/* 10.4/3 An abstract class shall not be used as a parameter type,
as a function return type or as type of an explicit
conversion. */
else if (abstract_virtuals_error (is_throw ? ACU_THROW : ACU_CATCH, type))
return false;
else if (!is_throw
&& TREE_CODE (type) == REFERENCE_TYPE
&& TYPE_REF_IS_RVALUE (type))
{
error ("cannot declare catch parameter to be of rvalue "
"reference type %qT", type);
return false;
}
else if (variably_modified_type_p (type, NULL_TREE))
{
if (is_throw)
error ("cannot throw expression of type %qT because it involves "
"types of variable size", type);
else
error ("cannot catch type %qT because it involves types of "
"variable size", type);
return false;
}
return true;
}
static bool
is_admissible_throw_operand_or_catch_parameter (tree t, bool is_throw)
{
tree expr = is_throw ? t : NULL_TREE;
tree type = TREE_TYPE (t);
/* C++11 [except.handle] The exception-declaration shall not denote
an incomplete type, an abstract class type, or an rvalue reference
type. */
/* 15.1/4 [...] The type of the throw-expression shall not be an
incomplete type, or a pointer or a reference to an incomplete
type, other than void*, const void*, volatile void*, or
const volatile void*. Except for these restriction and the
restrictions on type matching mentioned in 15.3, the operand
of throw is treated exactly as a function argument in a call
(5.2.2) or the operand of a return statement. */
if (!complete_ptr_ref_or_void_ptr_p (type, expr))
return false;
/* 10.4/3 An abstract class shall not be used as a parameter type,
as a function return type or as type of an explicit
conversion. */
else if (ABSTRACT_CLASS_TYPE_P (type))
{
if (is_throw)
error ("expression %qE of abstract class type %qT cannot "
"be used in throw-expression", expr, type);
else
error ("cannot declare catch parameter to be of abstract "
"class type %qT", type);
return false;
}
else if (!is_throw
&& TREE_CODE (type) == REFERENCE_TYPE
&& TYPE_REF_IS_RVALUE (type))
{
error ("cannot declare catch parameter to be of rvalue "
"reference type %qT", type);
return false;
}
return true;
}
tree
expand_start_catch_block (tree decl)
{
tree exp;
tree type;
if (! doing_eh (1))
return NULL_TREE;
/* Make sure this declaration is reasonable. */
if (decl && !complete_ptr_ref_or_void_ptr_p (TREE_TYPE (decl), NULL_TREE))
decl = NULL_TREE;
if (decl)
type = prepare_eh_type (TREE_TYPE (decl));
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 = build2 (MINUS_EXPR, TREE_TYPE (exp), exp,
TYPE_SIZE_UNIT (TREE_TYPE (exp)));
exp = build_indirect_ref (exp, NULL);
initialize_handler_parm (decl, exp);
return type;
}
/* Call __cxa_end_catch at the end of processing the exception. */
push_eh_cleanup (type);
/* 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)
finish_expr_stmt (do_begin_catch ());
/* 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 (TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (decl)))
{
exp = do_get_exception_ptr ();
initialize_handler_parm (decl, exp);
finish_expr_stmt (do_begin_catch ());
}
/* 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 = do_begin_catch ();
exp = create_temporary_var (ptr_type_node);
DECL_REGISTER (exp) = 1;
cp_finish_decl (exp, init, NULL_TREE, LOOKUP_ONLYCONVERTING);
finish_expr_stmt (build_modify_expr (exp, INIT_EXPR, init));
initialize_handler_parm (decl, exp);
}
return type;
}
tree
expand_start_catch_block (tree decl)
{
tree exp;
tree type, init;
if (! doing_eh ())
return NULL_TREE;
/* Make sure this declaration is reasonable. */
if (decl && !complete_ptr_ref_or_void_ptr_p (TREE_TYPE (decl), NULL_TREE))
decl = error_mark_node;
if (decl)
type = prepare_eh_type (TREE_TYPE (decl));
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;
}
tree
expand_start_catch_block (tree decl)
{
tree exp = NULL_TREE;
tree type;
bool is_java;
if (! doing_eh (1))
return NULL_TREE;
/* Make sure this declaration is reasonable. */
if (decl && !complete_ptr_ref_or_void_ptr_p (TREE_TYPE (decl), NULL_TREE))
decl = NULL_TREE;
if (decl)
type = prepare_eh_type (TREE_TYPE (decl));
else
type = NULL_TREE;
is_java = false;
if (decl)
{
tree init;
if (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. */
init = build_exc_ptr ();
init = build1 (NOP_EXPR, build_pointer_type (type), init);
init = build (MINUS_EXPR, TREE_TYPE (init), init,
TYPE_SIZE_UNIT (TREE_TYPE (init)));
init = build_indirect_ref (init, NULL);
is_java = true;
}
else
{
/* C++ requires that we call __cxa_begin_catch to get the
pointer to the actual object. */
init = do_begin_catch ();
}
exp = create_temporary_var (ptr_type_node);
DECL_REGISTER (exp) = 1;
cp_finish_decl (exp, init, NULL_TREE, LOOKUP_ONLYCONVERTING);
finish_expr_stmt (build_modify_expr (exp, INIT_EXPR, init));
}
else
finish_expr_stmt (do_begin_catch ());
/* C++ requires that we call __cxa_end_catch at the end of
processing the exception. */
if (! is_java)
push_eh_cleanup (type);
if (decl)
initialize_handler_parm (decl, exp);
return type;
}
