/* Handle exceptional things in C++.
Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009
+ 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010
Free Software Foundation, Inc.
Contributed by Michael Tiemann <tiemann@cygnus.com>
Rewritten by Mike Stump <mrs@cygnus.com>, based upon an
static int complete_ptr_ref_or_void_ptr_p (tree, tree);
static bool is_admissible_throw_operand (tree);
static int can_convert_eh (tree, tree);
-static gimple cp_protect_cleanup_actions (void);
+static tree cp_protect_cleanup_actions (void);
/* Sets up all the global eh stuff that needs to be initialized at the
start of compilation. */
call_unexpected_node
= push_throw_library_fn (get_identifier ("__cxa_call_unexpected"), tmp);
- if (targetm.arm_eabi_unwinder)
- unwind_resume_libfunc = init_one_libfunc ("__cxa_end_cleanup");
- else
- default_init_unwind_resume_libfunc ();
-
lang_protect_cleanup_actions = &cp_protect_cleanup_actions;
}
/* Returns an expression to be executed if an unhandled exception is
propagated out of a cleanup region. */
-static gimple
+static tree
cp_protect_cleanup_actions (void)
{
/* [except.terminate]
When the destruction of an object during stack unwinding exits
using an exception ... void terminate(); is called. */
- return gimple_build_call (terminate_node, 0);
+ return terminate_node;
}
static tree
tree
build_exc_ptr (void)
{
- return build0 (EXC_PTR_EXPR, ptr_type_node);
+ return build_call_n (built_in_decls [BUILT_IN_EH_POINTER],
+ 1, integer_zero_node);
}
/* Declare a function NAME, returning RETURN_TYPE, taking a single
static int
dtor_nothrow (tree type)
{
- if (type == NULL_TREE)
+ if (type == NULL_TREE || type == error_mark_node)
return 0;
- if (!CLASS_TYPE_P (type))
+ if (TYPE_HAS_TRIVIAL_DESTRUCTOR (type))
return 1;
if (CLASSTYPE_LAZY_DESTRUCTOR (type))
/* Make sure we mark the catch param as used, otherwise we'll get a
warning about an unused ((anonymous)). */
TREE_USED (decl) = 1;
+ DECL_READ_P (decl) = 1;
/* Figure out the type that the initializer is. Pointers are returned
adjusted by value from __cxa_begin_catch. Others are returned by
expand_start_catch_block (tree decl)
{
tree exp;
- tree type;
+ tree type, init;
if (! doing_eh (1))
return NULL_TREE;
fold_build1_loc (input_location,
NEGATE_EXPR, sizetype,
TYPE_SIZE_UNIT (TREE_TYPE (exp))));
- exp = cp_build_indirect_ref (exp, NULL, tf_warning_or_error);
+ 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)
- finish_expr_stmt (do_begin_catch ());
+ 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
{
exp = do_get_exception_ptr ();
initialize_handler_parm (decl, exp);
- finish_expr_stmt (do_begin_catch ());
+ finish_expr_stmt (init);
}
/* Otherwise the type uses a bitwise copy, and we don't have to worry
copy with the return value of __cxa_end_catch instead. */
else
{
- tree init = do_begin_catch ();
tree init_type = type;
/* Pointers are passed by values, everything else by reference. */
tree
begin_eh_spec_block (void)
{
- tree r = build_stmt (input_location, EH_SPEC_BLOCK, NULL_TREE, NULL_TREE);
+ tree r;
+ /* A noexcept specification (or throw() with -fnothrow-opt) is a
+ MUST_NOT_THROW_EXPR. */
+ if (TYPE_NOEXCEPT_P (TREE_TYPE (current_function_decl)))
+ {
+ r = build_stmt (input_location, MUST_NOT_THROW_EXPR, NULL_TREE);
+ TREE_SIDE_EFFECTS (r) = 1;
+ }
+ else
+ r = build_stmt (input_location, EH_SPEC_BLOCK, NULL_TREE, NULL_TREE);
add_stmt (r);
- EH_SPEC_STMTS (r) = push_stmt_list ();
+ TREE_OPERAND (r, 0) = push_stmt_list ();
return r;
}
{
tree raises;
- EH_SPEC_STMTS (eh_spec_block) = pop_stmt_list (EH_SPEC_STMTS (eh_spec_block));
+ TREE_OPERAND (eh_spec_block, 0)
+ = pop_stmt_list (TREE_OPERAND (eh_spec_block, 0));
+
+ if (TREE_CODE (eh_spec_block) == MUST_NOT_THROW_EXPR)
+ return;
/* Strip cv quals, etc, from the specification types. */
for (raises = NULL_TREE;
tree cleanup;
tree object, ptr;
tree tmp;
- tree temp_expr, allocate_expr;
- bool elided;
+ tree allocate_expr;
/* The CLEANUP_TYPE is the internal type of a destructor. */
if (!cleanup_type)
allocate_expr = do_allocate_exception (temp_type);
allocate_expr = get_target_expr (allocate_expr);
ptr = TARGET_EXPR_SLOT (allocate_expr);
- object = build_nop (build_pointer_type (temp_type), ptr);
- object = cp_build_indirect_ref (object, NULL, tf_warning_or_error);
+ TARGET_EXPR_CLEANUP (allocate_expr) = do_free_exception (ptr);
+ CLEANUP_EH_ONLY (allocate_expr) = 1;
- elided = (TREE_CODE (exp) == TARGET_EXPR);
+ 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))
}
}
else
- exp = build2 (INIT_EXPR, temp_type, object,
- decay_conversion (exp));
-
- /* Pre-evaluate the thrown expression first, since if we allocated
- the space first we would have to deal with cleaning it up if
- evaluating this expression throws.
-
- The case where EXP the initializer is a cast or a function
- returning a class is a bit of a grey area in the standard; it's
- unclear whether or not it should be allowed to throw. We used to
- say no, as that allowed us to optimize this case without worrying
- about deallocating the exception object if it does. But that
- conflicted with expectations (PR 13944) and the EDG compiler; now
- we wrap the initialization in a TRY_CATCH_EXPR to call
- do_free_exception rather than in a MUST_NOT_THROW_EXPR, for this
- case only.
-
- BUT: Issue 475 may do away with this inconsistency by removing the
- terminate() in this situation.
-
- Note that we don't check the return value from stabilize_init
- because it will only return false in cases where elided is true,
- and therefore we don't need to work around the failure to
- preevaluate. */
- temp_expr = NULL_TREE;
- stabilize_init (exp, &temp_expr);
-
- /* Wrap the initialization in a CLEANUP_POINT_EXPR so that cleanups
- for temporaries within the initialization are run before the one
- for the exception object, preserving LIFO order. */
- exp = build1 (CLEANUP_POINT_EXPR, void_type_node, exp);
+ {
+ tmp = decay_conversion (exp);
+ if (tmp == error_mark_node)
+ return error_mark_node;
+ exp = build2 (INIT_EXPR, temp_type, object, tmp);
+ }
- if (elided)
- exp = build2 (TRY_CATCH_EXPR, void_type_node, exp,
- do_free_exception (ptr));
- else
- exp = build1 (MUST_NOT_THROW_EXPR, void_type_node, exp);
+ /* 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);
- if (temp_expr)
- {
- /* Prepend the calculation of the throw expression. Also, force
- any cleanups from the expression to be evaluated here so that
- we don't have to do them during unwinding. But first wrap
- them in MUST_NOT_THROW_EXPR, since they are run after the
- exception object is initialized. */
- cp_walk_tree_without_duplicates (&temp_expr, wrap_cleanups_r, 0);
- exp = build2 (COMPOUND_EXPR, TREE_TYPE (exp), temp_expr, exp);
- exp = build1 (CLEANUP_POINT_EXPR, TREE_TYPE (exp), 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)));