[Bug c/86377] extern int errno; is treated as buggy function declaration [-Werror=strict-prototypes]

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86377

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
NEED_DECLARATION_ERRNO should not be defined for most targets/hosts.  You need
to figure out why it is being defined here.  Look at config.log to figure that
out.