LLVM ERROR: Cannot yet select: error

Question

Hello i am getting the following error when I am running my app in the simulator.

LLVM ERROR: Cannot yet select: ...

It seems that other have reported similar issues for the same combo:
* New sandy bridge MBP
* Iphone 4.3 Simulator
* opengl

Anyone have some clue?

Here is a short excerpt from the log:

LLVM ERROR: Cannot yet select: 0xa0237d8: v16i8 = bit_convert 0xa02aa48 [ORD=259] [ID=170]
  0xa02aa48: v8i16 = X86ISD::PSHUFLW 0xa02a828, 0xa02a608 [ID=166]
    0xa02a828: v8i16 = X86ISD::PSHUFHW 0xa0235b8, 0xa02a608 [ID=162]
      0xa0235b8: v8i16 = llvm.x86.sse2.packssdw.128 0xa023530, 0xa0234a8, 0xa023420 [ORD=256] [ID=158]
        0xa023530: i32 = Constant<647> [ORD=256] [ID=21]
        0xa0234a8: v4i32 = bit_convert 0xa023310 [ORD=255] [ID=139]
          0xa023310: v4f32 = llvm.x86.sse.cmp.ps 0xa023200, 0xa028d70, 0xb03c4e8, 0xa023288 [ORD=252] [ID=130]
            0xa023200: i32 = Constant<784> [ORD=252] [ID=19]

Answer 1

In case this helps anyone, I was having the same problem too, but don't have the older SDK for the other fix here. Kazuki posted a link to a discussion over at Apple, and it looks like its a bug that a few people have reported, but that it has something to do with the simulator. That being said, the app I was having a problem with runs fine on-device for me, so that's another potential workaround while this is looked at more.

Answer 2

I had the same Error on my MacBook Pro Intel Core i7 in the 4.3 simulator. I updated to Xcode 4.0.2 and now its working again.

Answer 3

This means that LLVM cannot do the instruction selection for some code. Usually this happens when you request some target-specific stuff in the code and disable the features via cmdline.

For example, if you'll use sse2 gcc intrinsics, but will compile for, say, i486, the same sort of message might occur (if not caught earlier by a frontend).

It's hard to say anything more definite without the full error line.

Answer 4

I'm getting this same error. I just got the new sandy bridge MBP today, and on my previous computer, I do not have this problem.

Changing the target to iPad 4.2 instead of iPad 4.3 resolves the issue.

Here's how to change the target in the new version of Xcode:

http://developer.apple.com/library/mac/#documentation/IDEs/Conceptual/Xcode4TransitionGuide/Orientation/Orientation.html

Answer 5

I had the same situation. It looks like a bug of LLVM 2.8 for the new sandy bridge. The work around is to use 4.2 simulator as NoEvilPeople said.

• OpenGL apps exit in 4.3 Sim but work...
• MacRuby build issues with LLVM
• Attempt to force LLVM to treat sandy bridge as core2