https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78188
--- Comment #12 from Richard Biener <rguenth at gcc dot gnu.org> --- Breakpoint 8, symtab_node::set_comdat_group (this=0x2aaaaf05ea10, group=<identifier_node 0x2aaaaf3d4370 _ZN10hash_tableI13vn_phi_hasher11xcallocatorE19find_slot_with_hashERKP8vn_phi_sj13insert_option>) at /space/rguenther/src/gcc-git/gcc/cgraph.h:218 218 || DECL_P (group)); (gdb) p this->decl $17 = <function_decl 0x2aaaaff46d00 _ZL11vn_valueizeP9tree_node.part.80> from IPA comdat. Now trying to reduce the testcase.