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Date: Fri, 22 Apr 2005 15:48:45 -0400 (EDT)
From: Daniel Eischen <deischen@freebsd.org>
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To: Scott Long <scottl@samsco.org>
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cc: sgk@troutmask.apl.washington.edu
cc: peter@freebsd.org
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Subject: Re: libpthread version bump
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On Fri, 22 Apr 2005, Scott Long wrote:

> Warner Losh wrote:
> >>Having lived through the std{io,err,out} libc snafu, the
> >>libm.so.2 snafu, and now the libc.so.5/libpthread.so.1
> >>problem, I will once again suggest that *ALL* library
> >>version numbers should be bumped when a new branch is
> >>created.
> >
> >
> > Yes.  When a library version is bumped, *ALL* libraries that depend on
> > it need to be bumped.  Sadly, this has proven to be too difficult
> > because it would create an unholy maintanence problem for the ports.
> >
> > Warner
>
> Well, there is indeed a problem at the moment of libc being bumped for
> 6-current but not libpthread.  However, I think that the particular
> problem with the fs/gs change goes above and beyond this problem.  So,
> we have about 2 months to sort this all out.  Any volunteers?

I'm not sure I fully understand the problem, but can't you
just make libpthread avoid using *setbase() if the symbol
isn't available and use the ldt functions as a fallback?

	#pragma weak	i386_get_gsbase
	static void *have_gsbase = i386_get_gsbase;

	...

	if (have_gsbase == NULL) {
		/* use ldt stuff */
	}
	else {
		/* use i386_get_gsbase */
	}

You just need something else to force the symbol i386_get_gsbase
to be loaded; the #pragma weak won't force it to be loaded even
if it is present.

-- 
DE