Re: Trying to boot Vaxstation using mopd

[Greg Stark <stark%mit.edu@localhost>]

On Mon, Jun 27, 2016 at 11:02 PM, Tom Ivar Helbekkmo
<tih%hamartun.priv.no@localhost> wrote:
>> Well the awk core dumps were presumably [...]
>
> I don't know if this is still an issue, but there's been a problem in
> the past, specific to the VAX because of its different floating point
> implementation, where if awk sees a string token beginning with the
> characters "nan", case independent, it'll read it as a NaN float, and
> promptly dump core.

Well there's two problems with the theory that it's floating-point
related. 1) It's non-deterministic. I would expect most circumstances
like you describe to be repeatable. and 2) things like 1/0 and 0/0 on
VAX don't cause SIGILL, they cause floating point exceptions which
would indeed core-dump but I'm seeing SIGILL. It happens that log(0)
and other libm functions do indeed signal errors via SIGILL but it
seems somewhat less likely that awk would be doing anything like that
to generate an Inf or NaN.

> May not be relevant - it's been a while since I had a VAX that could run
> NetBSD - but just thought I'd mention it.  :)

This is my new toy :)


-- 
greg