https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105518
--- Comment #2 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:be124477b38a71ba8ba0b24d859ae764bb44a4eb commit r13-4729-gbe124477b38a71ba8ba0b24d859ae764bb44a4eb Author: Patrick Palka <ppa...@redhat.com> Date: Thu Dec 15 15:54:31 2022 -0500 c++: local alias in typename in lambda [PR105518] We substitute the qualifying scope of a TYPENAME_TYPE directly using tsubst_aggr_type (so that we can pass entering_scope=true) instead of going through tsubst, which means we don't properly reuse typedefs during this substitution. This ends up causing us to reject the below testcase because we substitute the TYPENAME_TYPE alias::type as if it were written without the A<t> alias, and thus we expect the non-capturing lambda to capture t. This patch fixes this by making tsubst_aggr_type delegate typedefs to tsubst so that get consistently reused, and then adjusting the result appropriately if entering_scope is true. In passing, this refactors tsubst_aggr_type into two functions, one that's intended to be called directly and a more minimal one that's intended to be called only from the RECORD/UNION/ENUMERAL_TYPE cases of tsubst (and contains only the necessary bits for that call site). PR c++/105518 gcc/cp/ChangeLog: * pt.cc (tsubst_aggr_type): Handle typedefs by delegating to tsubst and adjusting the result if entering_scope. Split out the main part of the function into ... (tsubst_aggr_type_1) ... here. (tsubst): Use tsubst_aggr_type_1 instead of tsubst_aggr_type. Handle TYPE_PTRMEMFUNC_P RECORD_TYPEs here instead of in tsubst_aggr_type_1. gcc/testsuite/ChangeLog: * g++.dg/cpp0x/lambda/lambda-alias1.C: New test.
