Re: ppc situation

[Geoff Keating <geoffk at geoffk dot org>]

> From: "Jack Howarth" <howarth@nitro.med.uc.edu>
> Date: Sat, 30 Jun 2001 15:39:29 -0400
> 
> Hello,
>    If I understand the current situation with the powerpc arch
> in glibc cvs, a number of programs will have to be patched to
> compile with -fpic to work correctly including some of kde 2.1.1.
> It appears that the stock 2.2.3 glibc release doesn't have this
> problem but that the current cvs does since debian glibc 2.2.3-6
> packages causes such breakage on debianppc. If the libc developers
> are going to release a glibc 2.2.4 which exposes such breakage
> under the glibc 2.2.4 what will be done to help identify these
> problem programs? I can see a lot of confusion occuring when
> users attempt to upgrade from 2.2.3 to 2.2.4 (which should be
> a minor upgrade for them) and find a slew of programs no longer
> function. It is most unfortunate that this problem wasn't found
> at a point where we could have used versioning eliminate the problem.
> Thanks in advance for any information on this as it seems like
> something that will causes a lot of bandwidth to be eaten up on
> the ppclinux support mailing lists once glibc 2.2.4 is released.
> I think at the very least we should start a list of programs known
> to be tickled by this missing -fpic problem so the maintainers can
> be put on notice. With any luck the bulk of them might have minor
> releases of their programs out with the proper -fpic fix in their
> makefiles before glibc 2.2.4 ever is released. 

I think you misunderstand.  This is not "new".  It just happens to be
more visible due to a bug in glibc.  Well-configured systems will
never see the bug (the only effect is on performance) and so of course
testing did not show the problem.

You can easily detect the affected shared libraries by performing

objdump -p foo.so | grep TEXTREL

any libraries which match could potentially cause the problem and need
to be corrected.

If you wanted to detect it at link time (of the shared libraries), you
could use the '-z text' option to ld, but for the fact that it's not
implemented in GNU ld at present.

-- 
- Geoffrey Keating <geoffk@geoffk.org>