FatELF

Posted Jun 3, 2011 12:14 UTC (Fri) by jzbiciak (guest, #5246)
Parent article: Illumos: the successor to the OpenSolaris community

I think I somehow missed the FatELF article the first time it went around. This is a feature I'd love to see. I wish I had it 5 years ago.

I'm in a mixed-architecture environment at work (mixture of 32-bit and 64-bit Linux). Everything is shared via NFS.

For the stuff I compile myself, I make sure to compile it for 32 bit to ensure it'll run everywhere. Far too often, though, I run into problems where someone's made the official build of an internal tool 64 bit only, so I have to go to a 64 bit host via a crummy LSF interactive session to run it. LSF makes things mostly, but not entirely transparent, and the beancounters don't like me leaving interactive sessions open when I'm not using them so I lose shell history, etc. if I need to wander away from a session for awhile.

If we had FatELF, we could just build all our tools for both 32-bit and 64-bit, and the right version would get used "magically."

I've made use of the Mach-O fat binaries in the past, and I can attest that they make life much easier when you have to share code across architectures. Apple patched their GCC to makes it pretty darn painless to build a multi-arch Mach-O file. All you do is add a string of "-arch foo" flags to CFLAGS and you're done. I release cross-compiled versions of my Intellivision emulator, compiled for PPC and Intel, all compiled from either my ancient G3 or my wife's MacBook Pro.

I don't really understand all the negativity toward FatELF that was displayed in the FatELF thread. It would nuke the /lib32 and /lib64 abominations, and make more things "just work." Bloat? Sure, but you don't have to use it everywhere, and you could always strip away the unneeded architectures from 3rd party binaries if you really care about the disk space.

I personally hope Stormont's experiment goes well.

Flip side is that even if it does, I probably won't benefit from it. My workstation still runs RHEL WS 4, and probably will until it gets replaced. By the time we'd upgrade to an OS with FatELF support, we probably won't have any more 32-bit systems deployed.