https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120125
--- Comment #4 from Nathaniel Shead <nshead at gcc dot gnu.org> ---
FWIW I have a WIP patch that fixes the ICE (also for the original testcase):
diff --git a/gcc/cp/optimize.cc b/gcc/cp/optimize.cc
index 6f9a77f407a..fc4d6c2e351 100644
--- a/gcc/cp/optimize.cc
+++ b/gcc/cp/optimize.cc
@@ -309,8 +309,8 @@ maybe_thunk_body (tree fn, bool force)
defer_mangling_aliases = save_defer_mangling_aliases;
cgraph_node::get_create (fns[0])->set_comdat_group (comdat_group);
cgraph_node::get_create (fns[1])->add_to_same_comdat_group
- (cgraph_node::get_create (fns[0]));
- symtab_node::get (fn)->add_to_same_comdat_group
+ (cgraph_node::get (fns[0]));
+ symtab_node::get_create (fn)->add_to_same_comdat_group
(symtab_node::get (fns[0]));
if (fns[2])
/* If *[CD][12]* dtors go into the *[CD]5* comdat group and dtor is
though I think there's another bigger issue somewhere to do with how we've
handled imported explicit instantiations of inline constructors with
'-fdeclone-ctor-dtor', as the generated code doesn't look right to me. Maybe
this patch would be sufficient for backporting to 14/15 though.
