Date: Tue, 13 Sep 2005 21:07:41 -0600 (MDT)
From: Marc Aurele La France <tsi@ualberta.ca>
To: Sam Hartman via RT <rt-comment@krbdev.mit.edu>
Subject: Re: [krbdev.mit.edu #3176]
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References: <rt-3176-14560.8.57294128257266@krbdev.mit.edu>
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On Tue, 13 Sep 2005, Sam Hartman via RT wrote:
>>>>>> "Marc" == Marc Aurele La France <tsi@ualberta.ca> writes:
>    Marc> On Tue, 13 Sep 2005, Sam Hartman via RT wrote:
>    >> Note that the patch to shlib.conf breaks our ABI on AIX.

>    Marc> How so?  How can wrapping, or not, a shared object into an
>    Marc> archive affect a programming interface?  And why is this
>    Marc> wrapping preferable to producing dlopen'able objects?

> Because it changes the name that appears in the liblist section of the
> xcoff object.

... of the _referencing_ xcoff objects, yes.  That's a good point WRT 
compatibility with previous releases of mit-krb5 and/or AIX.  But, at least 
on AIX 5.3, the run-time loader doesn't seem to care whether a referenced .a 
contains shared or static objects.  So old binaries should be OK.

You must admit, though, that the current scheme, before my patch, prevents 
shared/static co-existence, which is not a Good Thing (tm).

>    Marc> Quite frankly, I find it odd that this wrapping is only
>    Marc> being done for AIX, and only by mit-krb5.  Even GNU doesn't
>    Marc> do this.  Is this a remnant of the historical
>    Marc> misundertanding of how AIX shared objects are supposed to
>    Marc> work?

> No.  It's because I actually understood conventions used for the C
> libraries on AIX 3.1, 3.2 and 4.  AIX 4.3 did add optional conventions
> for non-wrapped objects, although it was not clear the linker did a
> good job of finding them when first introduced.

Well, I still have an AIX 3.2.5 system around.  So I can offer to try this 
out there and get back to you.

Marc.

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