[Bug c++/66571] Template substitution causes some OpenMP rejects-valid

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66571

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 35793
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35793&action=edit
gcc6-pr66571.patch

Untested fix.