Hi!
build_cplus_new can return error_mark_node e.g. when calling a deleted
ctor or dtor, but bot_manip was assuming it will always return
AGGR_INIT_EXPR. As it is generally unsafe to set subexpressions to
error_mark_node, e.g. cp_fold ICEs if binary expression has one of its
operand error_mark_node, the patch instead arranges for the whole
break_out_target_exprs to return error_mark_node in that case.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2018-02-19 Jakub Jelinek <ja...@redhat.com>
PR c++/84449
* tree.c (bot_manip): If build_cplus_new or break_out_target_exprs
returns error_mark_node, return it immediately.
(break_out_target_exprs): If cp_walk_tree with bot_manip returns
error_mark_node, return error_mark_node.
* g++.dg/cpp0x/constexpr-84449.C: New test.
--- gcc/cp/tree.c.jj 2018-02-10 00:22:01.000000000 +0100
+++ gcc/cp/tree.c 2018-02-19 11:54:55.815478346 +0100
@@ -2896,6 +2896,8 @@ bot_manip (tree* tp, int* walk_subtrees,
{
u = build_cplus_new (TREE_TYPE (t), TREE_OPERAND (t, 1),
tf_warning_or_error);
+ if (u == error_mark_node)
+ return u;
if (AGGR_INIT_ZERO_FIRST (TREE_OPERAND (t, 1)))
AGGR_INIT_ZERO_FIRST (TREE_OPERAND (u, 1)) = true;
}
@@ -2913,6 +2915,8 @@ bot_manip (tree* tp, int* walk_subtrees,
(splay_tree_value) TREE_OPERAND (u, 0));
TREE_OPERAND (u, 1) = break_out_target_exprs (TREE_OPERAND (u, 1));
+ if (TREE_OPERAND (u, 1) == error_mark_node)
+ return error_mark_node;
/* Replace the old expression with the new version. */
*tp = u;
@@ -3025,7 +3029,8 @@ break_out_target_exprs (tree t)
target_remap = splay_tree_new (splay_tree_compare_pointers,
/*splay_tree_delete_key_fn=*/NULL,
/*splay_tree_delete_value_fn=*/NULL);
- cp_walk_tree (&t, bot_manip, target_remap, NULL);
+ if (cp_walk_tree (&t, bot_manip, target_remap, NULL) == error_mark_node)
+ t = error_mark_node;
cp_walk_tree (&t, bot_replace, target_remap, NULL);
if (!--target_remap_count)
--- gcc/testsuite/g++.dg/cpp0x/constexpr-84449.C.jj 2018-02-19
12:04:51.518530240 +0100
+++ gcc/testsuite/g++.dg/cpp0x/constexpr-84449.C 2018-02-19
12:04:26.643528069 +0100
@@ -0,0 +1,14 @@
+// PR c++/84449
+// { dg-do compile { target c++11 } }
+
+struct A
+{
+ constexpr A (int) {}
+ ~A () = delete;
+};
+
+struct B
+{
+ A a;
+ constexpr B () : a (0) {} // { dg-error "use of deleted function" }
+};
Jakub
