[Bug c++/66153] Internal compiler error in nested template function

[paboyle at ph dot ed.ac.uk]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66153

--- Comment #6 from Peter Boyle <paboyle at ph dot ed.ac.uk> ---
Just an update:
Still fails in G++ 7.1.0 and in 8.0.0 (head) on Wandbox.
Still passes in Clang 4.0.0 and 5.0.0(head).