[OE-core] multilib theory & practice

[Kumar Gala]

On Aug 6, 2011, at 3:56 PM, Kumar Gala wrote:

> I'm looking at trying to get multilib working for powerpc.  However I'm a bit lost in how this is suppose to work from a few different perspectives:
> 
> 1. from user perspective (I'm starting with a 64-bit build in /lib64 and adding 32-bit that would be in /lib):
> 
> (i've added in local/conf):
> require conf/multilib.conf
> MULTILIBS = "multilib:lib"
> DEFAULTTUNE_virtclass-multilib-lib = "powerpc"
> 
> What should this end up producing?  Do I get a 32-bit set of libs built automatically?  What else do I need to do?
> 
> 2. From a infrastructure point of view:
> 
> * Do have a single compiler that is multi-arch or 2 compilers? (not sure how the x86_64 toolchain works today)
> * what areas should I investigate that might need tweaking that are arch specific?
> * should I see different task names for the new multilib builds? (or the 32-bit specific builds?)

To add to this I'm wondering how we get proper eglibc for 32-bit, how we get proper gcc libs (libgcc, etc).

- k