r193528 - Support cross linking to arm on ubuntu.

[Rafael Espíndola]

>> What is the characteristic of the tree that should make us conclude it
>> is biarch? The existence of the lib64 directory itself?
>
>
> That is the best metric I have come up with.
>
> Essentially, the pattern I have followed is to assume that all possible
> forms of biarch could occur and should be respected. If you create 'lib64',
> 'lib32' and 'lib', you'll be able to get GCC to search all 3 with variants
> of '-m32' and '-m64'. =/

OK. The problem without the patch was when the host system was biarch
(had a lib32) but the target was not (arm). Since we tried lib32
first, we found the host files.

I will try to code a patch that explicitly checks for lib64/lib32
existing in the target dirs and uses that to decide if it should use
biarch support.

Just to make sure: In your  setup you have lib32 and/or lib64 but
GCCInstallation.getBiarchSuffix() is empty? Is the gcc detection
correct about that?

Cheers,
Rafael