https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95291
--- Comment #8 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Patrick Palka <ppa...@gcc.gnu.org>: https://gcc.gnu.org/g:bcd77b7b9f35bd5b559ed593c3b3e346c1e6f364 commit r12-100-gbcd77b7b9f35bd5b559ed593c3b3e346c1e6f364 Author: Patrick Palka <ppa...@redhat.com> Date: Sat Apr 24 00:14:29 2021 -0400 c++: do_class_deduction and dependent init [PR93383] Here we're crashing during CTAD with a dependent initializer (performed from convert_template_argument) because one of the initializer's elements has an empty TREE_TYPE, which ends up making resolve_args unhappy. Besides the case where we're initializing one template placeholder from another, which is already specifically handled earlier in do_class_deduction, it seems we can't in general correctly resolve a template placeholder using a dependent initializer, so this patch makes the function just punt until instantiation time instead. gcc/cp/ChangeLog: PR c++/89565 PR c++/93383 PR c++/95291 PR c++/99200 PR c++/99683 * pt.c (do_class_deduction): Punt if the initializer is type-dependent. gcc/testsuite/ChangeLog: PR c++/89565 PR c++/93383 PR c++/95291 PR c++/99200 PR c++/99683 * g++.dg/cpp2a/nontype-class39.C: Remove dg-ice directive. * g++.dg/cpp2a/nontype-class45.C: New test. * g++.dg/cpp2a/nontype-class46.C: New test. * g++.dg/cpp2a/nontype-class47.C: New test. * g++.dg/cpp2a/nontype-class48.C: New test.