by slembcke » Sat Sep 22, 2012 2:03 pm
I saw your email on Thursday. Sorry I didn't have time to get around to it yet.
So it's a little complicated right now. Apple decided to introduce the armv7s instruction set while removing support for armv6 in the same SDK version. -_- I don't think armv6 was ever even officially deprecated, although the writing has certainly been on the wall for some time due to crummy support for it.
The iPhone 5 will be able to run armv6, armv7 and armv7s code just fine as the instruction sets are backwards compatible. Otherwise only brand new apps released in the last several days would work on it. The advantage of compiling for armv7s is potentially more speed. It's 100% unclear what the advantage is though, supposedly it supports new VFP instructions, but those aren't going to help out most code unless you are specifically targeting them with intrinsics. Other than that, there seems to be no information on what the difference actually is. Removing armv7s from the architectures to build for won't break anything, and it will almost certainly still run armv7 code faster than an iPhone 4s.
Another good reason to not include armv7s support is that I'm guessing that you don't actually have an iPhone 5 yet to test it on. Given Apple's track record with rushing out buggy versions of the Clang compiler whenever they release a new device... I really wouldn't trust it to actually work without seeing it running on a device in my hand. I've had to submit several compiler bug reports for armv6, armv7, x64 and ARC related issues in the past 9 months or so. In each case it involved a bunch of frustrating debugging in the disassembly. -_-
I might get an iPhone in the next month or two (first smartphone actually), but I personally am not terribly comfortable with releasing an official version of the library for armv7s without being able to test it. I can throw up a temporary build on the site if you really want though.