Re: [Qemu-devel] [ARM/FDPIC 1/4] linux-user: ARM-FDPIC: Add configure option to support loading of FDPIC binaries

[Christophe Lyon]

On 13/04/2018 17:04, Peter Maydell wrote:
> On 6 April 2018 at 16:17, Christophe Lyon <address@hidden> wrote:
> > Adds --enable-fdpic and --disable-fdpic configure options.  This
> > feature is disabled by default, that's why it is not described in the
> > "Optional features" help section (which are enabled by default if
> > possible).
> >
> > FDPIC ELF objects are identified with e_ident[EI_OSABI] ==
> > ELFOSABI_ARM_FDPIC.
>
> If we can identify these ELF objects by looking in the ELF header,
> why would we want to make this all a configure option that's
> disabled by default?
>
> I think we should just have support for these binaries enabled
> always. Otherwise it will bitrot because nobody compiles it.
We are relying on a pre-existing CONFIG_USE_FDPIC, which is currently
never defined. This was introduced by commit 1af02e83 back in 2011,
and indeed if you try to build QEMU with CONFIG_USE_FDPIC, the build fails 
because elf_is_fdpic() is not defined.

We tried to conform to this existing support, but maybe it's already bit-rotten?
Do you suggest removing CONFIG_USE_FDPIC?

Thanks



> thanks
> -- PMM
> .