https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70594
--- Comment #30 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Ah, the reason is clear,
hash_table<named_label_hasher> *x_named_labels;
hashes based on DECL_UID (that is fine), and adds the labels during hash table
traversal (which is not fine).
Both:
static void
pop_labels (tree block)
{
if (named_labels)
{
named_labels->traverse<tree, pop_labels_1> (block);
named_labels = NULL;
}
}
and
poplevel's
if (cfun && !functionbody && named_labels)
named_labels->traverse<cp_binding_level *, poplevel_named_label_1>
(current_binding_level);
look wrong in this regard.
