https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95158
--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-8 branch has been updated by Jason Merrill <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:a2bdff4f24d9065791e6d8820004772b9fe0c4c1 commit r8-10637-ga2bdff4f24d9065791e6d8820004772b9fe0c4c1 Author: Jason Merrill <ja...@redhat.com> Date: Wed Jun 3 23:50:06 2020 -0400 c++: Fix FE devirt with diamond inheritance [PR95158] This started breaking in GCC 8 because of the fix for PR15272; after that change, we (correctly) remember the lookup from template parsing time that found Base::foo through the non-dependent MiddleB base, and so we overlook the overrider in MiddleA. But given that, the devirtualization condition from the fix for PR59031 is insufficient; we know that d has to be a Derived, and we found Base::foo in Base, but forcing a non-virtual call gets the wrong function. Fixed by removing the PR59031 code, and instead looking up the overrider in BINFO_VIRTUALS. gcc/cp/ChangeLog: PR c++/95158 * class.c (lookup_vfn_in_binfo): New. * call.c (build_over_call): Use it. (build_new_method_call_1): Don't set LOOKUP_NONVIRTUAL. * cp-tree.h (resolves_to_fixed_type_p): Add default argument. (lookup_vfn_in_binfo): Declare. gcc/testsuite/ChangeLog: PR c++/95158 * g++.dg/template/virtual5.C: New test.
