[Bug c/70791] -Wnested-externs prints inconsistent column number

[egall at gwmail dot gwu.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70791

--- Comment #4 from Eric Gallager <egall at gwmail dot gwu.edu> ---
(In reply to Marek Polacek from comment #3)
> Fixed.

Thanks for the speedy response and fix!