Re: glibc 2.1 and gabi

[Mark Kettenis <kettenis at wins dot uva dot nl>]

   Date: Thu, 20 Jul 2000 23:22:18 -0700
   From: "H . J . Lu" <hjl@lucon.org>

   On Thu, Jul 20, 2000 at 11:21:12PM -0700, Geoff Keating wrote:
   > > Date: Thu, 20 Jul 2000 21:14:54 -0700
   > > From: "H . J . Lu" <hjl@lucon.org>
   > 
   > > On Thu, Jul 20, 2000 at 08:27:31PM -0700, Geoff Keating wrote:
   > > > I know I _can_ use it, but when do I _have_ to use it?  What would go
   > > > wrong if the linker never emitted any of these tags?
   > 
   > > The reason I added the support is Ulrich wanted DF_1_NODELETE for
   > > libpthread.so.
   > ...
   > 
   > So shouldn't we only use the new tags if the user specifies -z
   > nodelete (or whatever it is)?

   Yes, that is how it works. The new dtags will be generated only
   by either -z xxxxx or --enable-new-dtags.

Q: But why do you need --enable-new-dtags at all?

A: Because HJ sneaked in some patches that do more than just setting a
flag such as DF_1_NODELETE as a response for the user specifying a -z
nodelete.


2000-07-19  H.J. Lu  <hjl@gnu.org>

        * elf32-arm.h (elf32_arm_size_dynamic_sections): Also set
        DF_TEXTREL if DT_TEXTREL is set.
        * bfd/elflink.h (NAME(bfd_elf,size_dynamic_sections)): Also
        set DF_SYMBOLIC for symbolic link. Also set DT_RUNPATH if
        DT_RPATH is set.
        Set the DT_FLAGS and DT_FLAGS_1 entries if necessary.

Especially the DT_RUNPATH change is important.  This means that where
previously -rpath did only set DT_RPATH, it now also sets DT_RUNPATH.
As I understand it DT_RUNPATH is supposed to replace DT_RPATH in the
new ELF specs, but with slightly different semantics (at least on some
platfroms).  This makes me wonder whether setting both is really such
an idea.  I think that changes such as these deserve some deserve some
more discussion on the binutils list before they are made.  HJ, could
you please try to cooperate a bit more and give other people who
depend on the ELF linker a chance to comment on this kind of changes?

Mark