Re: Multilib and Linux.

[Philip Blundell <pb@nexus.co.uk>]

>Linux will move to multilib soon. I know egcs supports multilib.
>But I have some doubts how well it will work on Linux. ELF/PPC
>has 2 ABIs. But I don't know any Linux/PPC distribution supports
>both ABIs. I don't think the "nof" ABI is supported. I don't think
>it is trivial to build such a distribution. I don't even know if
>it is necessary for Linux. I'd like to hear what people's views
>on it.

In terms of EGCS it should be fine.  We have used multilibbing on ARM in the 
past to support both 26-bit and 32-bit ABIs, and I've also considered adding 
extra ABIs for floating-point related things.  At the moment the multilib stuff 
is turned off in the EGCS config files though because having it enabled means 
that everybody who wants to build the compiler needs to have both flavours of 
build environment set up (including glibc and so on).

The only place I can foresee problems is with shared libraries.  This isn't 
really a bridge we've crossed on the ARM yet.  We have EF_* values to tag the 
different ABIs in the ELF header so in theory the dynamic linker can be taught 
to only pull in the right sort of libraries, probably using the same hook that 
distinguishes libc5 vs libc6 shared objects.

p.