Bill, I'm not sure what you're talking about - R has separate files for each architecture. That approach ensures that we can choose the architecture at will. We don't use any 4-way executables (except for an extra copy of Rscript - there is a convenience fat binary, but each individual arch binary is kept aside, so you can still choose each arch). In fact, the default in the CRAN R is 32-bit for both ppc and Intel unless you choose 64-bit using --arch.
Cheers, Simon On Feb 25, 2008, at 10:44 PM, Bill Northcott wrote: > I notice that the FAT MacOS X binaries being built at the moment are > all 4 way fat. > > When a fat executable is launched, it will run as 64 bit, on a Mac > with G5 or Core2Duo processors. There is no way of overriding this > behaviour. > > On a Core2Duo machine this is good because the x86_64 ISA is a > considerable improvement on the old i386 one, and all applications > will generally run faster on this architecture in 64 bit. However, on > the G5 the ISAs are the same for both 32 and 64 bit, only the pointer > size changes. So that 64 bit actually runs more slowly. The only use > for ppc64 is for programs that need very large memory spaces on G5 > machines with at least 3GB of DRAM. I expect the sort of power users > who run such code and can afford large amounts of DRAM have upgraded > to a Mac Pro already. > > In short, I can see very little demand for ppc64 and including it just > reduces performance for those running G5 Macs. > > Hence my suggestion to make Universal Binaries 3 way fat i386, x86_64 > and ppc. > > Just a thought > Bill > > _______________________________________________ > R-SIG-Mac mailing list > [email protected] > https://stat.ethz.ch/mailman/listinfo/r-sig-mac > > _______________________________________________ R-SIG-Mac mailing list [email protected] https://stat.ethz.ch/mailman/listinfo/r-sig-mac
