> All this for the possibility of interposition? Yes, it seems so. The impact is there for this little-known and little-used feature. Instead of optimising for the common-case scenario where the symbols are not overridden, the ABI optimises for the corner case.
It also looks like PIE+PIC is required if you want a secure system with ASLR: <http://blog.flameeyes.eu/2009/11/02/the-pie-is-not-exactly-a....
Flameeyes (Gentoo dev) has sent patches to all the main library developer that make sure only the necessary number of symbols is exposed and as much data as possible is marked as read-only. I think this effort is more valuable than proposing a very unlikely ABI change.