[Bug c++/92992] Side-effects dropped when decltype(nullptr) typed expression is passed to ellipsis

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92992

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 47522
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=47522&action=edit
gcc10-pr92992.patch

Untested fix.