re: README: gcc 7 switch coming to a port near you!

[matthew green <mrg%eterna.com.au@localhost>]

the sparc installer (and likely sparc64 installer) issue should be
hacked around in -current, by not removing .eh_frame as previously
posted.  we can fix it properly later when we know why.

hopefully the sparc testbed will fix itself now.


the sparc smp problem i have tracked down (and it is not a gcc 7
specific issue) and i don't yet understand what is going, but i
have a very simple workaround for it as well.

the problem happens in the new npf module.  i saw this change in
my lists fairly often and ignored it, but i finally managed to
convince myself via bisect it was the problem.

as a guess, i hacked npf_modctl() to return ENOTTY instead of
calling npf_init().  this allowed my kernel to function fine.
i then noticed npf_init() is static and only called once from
npf_modctl(), and for some reason i tried compiling it with the
static removed.  this works.  i've confirmed this result a few
times because it is so surprising.

as a test, i inlind the contents directly and the same problem
occurs, so i suspect what ever is wrong happens when inlined.

i'm still trying to understand the full asm for either version
but i haven't yet figurd out what is wrong here.

this is very confusing, and if a compiler bug, is not a new one.


.mrg.