Re: [Valgrind-developers] Porting valgrind to FreeBSD

[Nicholas N. <nj...@ca...>]

On Sat, 3 Jan 2004, Doug Rabson wrote:

> > Well done!  A few people have tried this, but it sounds like you've got a
> > lot further than anyone else.  Would you be able to write some kind of
> > summary describing the changes you had to make?  That would be very useful
> > for people to get a grip on what you've done.
>
> I summarised most of the changes in a later message and you can get a
> patch against today's cvs at
> http://people.freebsd.org/~dfr/valgrind-20040103-dfr.diff.

Er, which message?  I only see a couple of brief descriptions... I was
thinking more along the lines of a page or two of summary -- more work for
you, I realise, but much easier for everyone else to understand than a
130KB diff...

> The most fiddly part was getting syscalls to work. FreeBSD (and probably
> all 4.4BSD derived systems) has a quite different syscall ABI with
> arguments on the stack and error-returns signalled with the carry flag.
> Add to that the fact that some (not all) syscalls return an extra 32bits
> in %edx and things get a bit tricky in vg_syscalls.c.

That's exactly the sort of thing I'd like to see in a summary (I don't
think you mentioned this previously)... what are the details of "things
get a bit tricky"?

N