Re: some odd library loading errors

[Szabolcs Nagy <nsz@port70.net>]

* Rich Felker <dalias@libc.org> [2015-11-17 10:55:45 -0500]:
> On Tue, Nov 17, 2015 at 04:45:16PM +0100, Szabolcs Nagy wrote:
> > 
> > i guess --disable-gnu-indirect-function could be the default when
> > gcc targets musl (assuming musl will not implement ifuncs anytime soon).
> 
> I think that's a reasonable assumption. Based on what I've seen
> lately, rather than finding solutions to the problems we knew about
> already, the rabbit hole keeps going deeper...
> 
> If you have reason to believe otherwise could you explain how we might
> reasonably support ifunc?
> 

well we can add support for ifunc by..

calling the ifunc resolver during reloc processing when STT_GNU_IFUNC
symbol or R_*_IRELATIVE reloc is found and in case of static linking
the relocs between __rel_iplt_{start,end} should be processed somehow.

the only ugliness is that passing arguments to the resolver is arch
specific.. and that there is no guarantee what the resolver might do
(but that's the same with glibc and it is something the user should
worry about)

i think even if musl does the reloc processing in different order
than glibc, this might work in practice and if the resolver crashes
we can say that it invoked ub.