https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89630
--- Comment #8 from Jason Merrill <jason at gcc dot gnu.org> --- Author: jason Date: Mon Mar 18 19:37:00 2019 New Revision: 269777 URL: https://gcc.gnu.org/viewcvs?rev=269777&root=gcc&view=rev Log: PR c++/89630 - ICE with dependent using-decl as template arg. Even though these two using-declarations have the same effect, they are not the same declaration, and we don't need to work to treat them as the same like we do for typedefs. If we did need to, we would need to handle them specially in iterative_hash_template_arg as well as here. * tree.c (cp_tree_equal): Always return false for USING_DECL. Modified: trunk/gcc/cp/ChangeLog trunk/gcc/cp/tree.c
