[Interest] qt5 universal binaries

[Tim Blechmann]

>> i've been trying to compile some universal binaries (i32/x86_64) of qt
>> 5.2. while i've been able to generate some libraries, mainly my
>> disabling precompiled headers and compiling without sse3/4/avx support,
>> i wonder: are UBs expected to work or will i run into some troubles?
>> (e.g. are the headers/mocs architecture-independenct)?
> 
> How far back do you need to support on your Macs? The last 32-bit only 
> Mac built was over 5 years ago, and we dumped everything before 10.6 
> about 2 years ago. 64 bit all the way makes things so much easier.

i don't care about ppc anymore, but ia32 is still an important target
for me, as i'm using qt from a plugin context and there are still a lot
of 32bit host applications around ...

tim