https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97938
--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-10 branch has been updated by Jason Merrill <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:5e7801808d2e9e99dc2931462c69a80c6f0e89cc commit r10-9840-g5e7801808d2e9e99dc2931462c69a80c6f0e89cc Author: Jason Merrill <ja...@redhat.com> Date: Fri Apr 2 11:05:46 2021 -0400 c++: lambda pack init-capture within generic lambda We represent the type of a pack init-capture as auto... with packs from the initializer stuck into PACK_EXPANSION_PARAMETER_PACKS so that expanding it produces the right number of elements. But when partially instantiating the auto..., we were changing PACK_EXPANSION_PARAMETER_PACKS to refer to only the auto itself. Fixed thus. gcc/cp/ChangeLog: PR c++/97938 * cp-tree.h (PACK_EXPANSION_AUTO_P): New. * lambda.c (add_capture): Set it. * pt.c (tsubst_pack_expansion): Handle it. gcc/testsuite/ChangeLog: PR c++/97938 * g++.dg/cpp2a/lambda-pack-init6.C: New test.