[Bug c++/78840] [5/6/7 Regression] ICE with const variables in templates implicitly captured by nested lambda expressions

[nathan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78840

--- Comment #2 from Nathan Sidwell <nathan at gcc dot gnu.org> ---
Created attachment 40379
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=40379&action=edit
reduced testcase.