Re: What exactly does --enable-new-dtags do?

[Alan Modra <amodra at bigpond dot net dot au>]

On Sun, Apr 03, 2005 at 06:49:29PM +0100, Mike Hearn wrote:
> Hi,
> 
> I would like to enable usage of DT_RUNPATH in my binaries, however the
> only way to get this is with the --enable-new-dtags switch, the
> exact effects of which are undocumented.

The action of the switch itself is reasonably self-documenting.  What's
not so obvious is which of the new dtags ld generates, and which tags
ld.so recognises.  Documentation on the latter probably doesn't belong
in ld.texinfo.  Some info on the new tags can be found at
http://docsun.cites.uiuc.edu/sun_docs/C/solaris_9/SUNWdev/LLM/p55.html

> I don't mind DT_RUNPATH because support for this was added to glibc in
> 1999, which is old enough that I think most of my users have upgraded by
> now. But I have no idea what else it does, so I have no idea how recent a
> system will be required by using this switch.
> 
> It seems to me that a switch with such vague semantics is a bit dangerous.
> Does anybody have a list of exactly what dyntags it enables? If not I'll
> rummage about in the code and try to produce one.
> 
> thanks -mike
> 

-- 
Alan Modra
IBM OzLabs - Linux Technology Centre