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

[Mike Hearn]

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.

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