[PATCH] elf: Support DT_RELR relative relocation format [BZ #27924]

[Joseph Myers]

On Mon, 11 Oct 2021, Fāng-ruì Sòng via Libc-alpha wrote:

> > While in line with the proposed spec additions I'm afraid the uses of
> > ElfW(Addr) here aren't universally correct: You assume that ELF
> > container type (size) expresses an aspect of the ABI. While this is
> > indeed the case for several arch-es, I think this has been a mistake.
> > IA-64, while meanwhile mostly dead, is (was) an example where 64-bit
> > code can validly live in a 32-bit ELF container (at least as far as
> > the psABI is concerned; I have no idea whether glibc actually
> > followed the spec). There's a separate ELF header flag indicating the
> > ABI, and hence the size of a pointer.
> 
> Thanks for chiming in.
> 
> As of ia64 buildability, it works for me:

As far as I know, glibc and the Linux kernel never supported ILP32 on ia64 
(HP-UX did).  But I'm not entirely clear whether the ILP32 ABI is what's 
being referred to here (cf. x32, MIPS n32, etc. - ILP32 ABIs using 64-bit 
instructions, and 32-bit ELF), or something else.

-- 
Joseph S. Myers
joseph@codesourcery.com