Re: ports and -current

On Sat, Sep 20, 2003 at 07:05:33PM -0600, M. Warner Losh wrote:
> Why does -pthread necessarily force selection of one specific
> threading library?  All it means is that it is that the program uses
> posix threads, at least traditionally.  How FreeBSD causes that to
> happen is an interesting implementation detail for some, but irrelvant
> for most ports.  Couldn't -pthread be made to give the user the
> default threading package, and for those that matter a more specific
> one can be specified?

This subject *has* been discussed both within FreeBSD and with the GCC
maintainers. I think that the consensus from those who chose to participate
in that discussion was that -pthread would be a noop on FreeBSD.

> It is insane to have FreeBSD be different than all other systems for
> this trivial reason.  Why fix everthing in the world when allowing
> -pthread to be a noop would solve the problem?  Seems like we're being
> overly picky for no real gain.  I guess I just don't understand.

Having -pthread as a noop doesn't fix the ports breakage. For years ports
have worked on the basis that libc_r was linked to get user-space threads
*instead* of libc. This was the result of certain people in the FreeBSD
developer community not wanting thread stubs in libc. Since libc was
linked by default (unless -nostdlib was specified), it was necessary to
have gcc know to use libc_r instead. That is why the -pthread argument
was added. FWIW, Linux and the other BSDs didn't have a -pthread argument
back then.

Now that libc has thread stubs in libc (in current), there is no longer
any need to have gcc know about any of the thread libraries. That's a
good thing IMO. The FSF wants GCC to have a -pthread argument on all
platforms and they are happy to have it as a noop.

I doubt that there would ever be a good time to make this change. The fact
that 4.9 has been delayed is making the problem seem worse because people
can't commit fixes to the tree. While 4.9 is delayed (due to the PAE
instability which never should have been allowed), the ports tree should
be unlocked. The fixes are simple. Make them and move on.

-- 
John Birrell