https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97582
--- Comment #3 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:cb168f779c87c1e0c37d22ea82dfb93ff8c873bc commit r11-7191-gcb168f779c87c1e0c37d22ea82dfb93ff8c873bc Author: Patrick Palka <ppa...@redhat.com> Date: Thu Feb 11 10:59:54 2021 -0500 c++: Fix ICE from op_unqualified_lookup [PR97582] In this testcase, we're crashing because the lookup of operator+ from within the generic lambda via lookup_name finds multiple bindings (C1::operator+ and C2::operator+) and returns a TREE_LIST thereof, something which op_unqualified_lookup (and push_operator_bindings) isn't prepared to handle. This patch extends op_unqualified_lookup and push_operator_bindings to handle such an ambiguous lookup result in the natural way. gcc/cp/ChangeLog: PR c++/97582 * name-lookup.c (op_unqualified_lookup): Handle an ambiguous lookup result by discarding it if the first element is a class-scope declaration, otherwise return it. (push_operator_bindings): Handle an ambiguous lookup result by doing push_local_binding on each element in the list. gcc/testsuite/ChangeLog: PR c++/97582 * g++.dg/cpp0x/lambda/lambda-template17.C: New test.