Re: musl on a different syscall layer?

[Justin Cormack <justin@specialbusservice.com>]

On Wed, Sep 17, 2014 at 7:02 PM,  <u-wsnj@aetey.se> wrote:
> On Wed, Sep 17, 2014 at 01:53:46PM -0400, Rich Felker wrote:
>> The main requirement is having equivalent functionality available. On
>> the BSD targets I've asked BSD folks about, there's supposedly no
>> equivalent of futex except inthe Linux compat layer, which is pretty
>> much a show-stopper unless/until it can be remedied. clone is a big
>> unknown to me too. The other big potential problem is if the native
>> syscall API requires a stack to communicate with the kernel (one or
>> more BSDs require this, IIRC), since at least __unmapself needs to be
>> able to call SYS_munmap and SYS_exit without a stack.
>
> Oh I see.
>
> This means "not much to hope for" (pity but good to know).

I don't think NetBSD uses the stack for syscalls on any common
architecture, maybe on some of the obscure ones, but maybe you don't
want to support them.

Adding futex support to NetBSD would be an interesting project; it is
not in the compat layer at present either, so that is a good reason to
add it. NetBSD is pretty friendly...

Justin (justin@netbsd.org)