https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106890
--- Comment #3 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-12 branch has been updated by Jason Merrill <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:94569d91bd4c604da755b4aae84256e7fe21196a commit r12-9441-g94569d91bd4c604da755b4aae84256e7fe21196a Author: Jason Merrill <ja...@redhat.com> Date: Sat Mar 18 08:27:26 2023 -0400 c++: DMI in template with virtual base [PR106890] When parsing a default member init we just build a CONVERT_EXPR for converting to a virtual base, and then expand that into the more complex form when we actually use the DMI in a constructor. But that wasn't working for the template case where we are considering the conversion at the point that the constructor needs the DMI instantiation, so it seemed like we were in a constructor already. And then when the other constructor tries to reuse the instantiation, it sees uses of the first constructor's parameters, and dies. So ensure that we get the CONVERT_EXPR in this case, too. PR c++/106890 gcc/cp/ChangeLog: * init.cc (maybe_instantiate_nsdmi_init): Don't leave current_function_decl set to a constructor. gcc/testsuite/ChangeLog: * g++.dg/cpp0x/nsdmi-template25.C: New test.