https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103769
--- Comment #9 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jason Merrill <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:07be8f8da4c6840a1fd6b2229b147e50cc6f03dc commit r12-7848-g07be8f8da4c6840a1fd6b2229b147e50cc6f03dc Author: Jason Merrill <ja...@redhat.com> Date: Fri Mar 25 11:26:06 2022 -0400 c++: ICE with alias in pack expansion [PR103769] This was breaking because when we stripped the 't' typedef in s<t<Args>...> to be s<Args...>, the TYPE_MAIN_VARIANT of "Args..." was still "t<Args>...", because type pack expansions are treated as types. Fixed by using the right function to copy a "type". PR c++/99445 PR c++/103769 gcc/cp/ChangeLog: * tree.cc (strip_typedefs): Use build_distinct_type_copy. gcc/testsuite/ChangeLog: * g++.dg/cpp0x/variadic-alias5.C: New test.