XCode 7 complains: building for iOS simulator, but linking in object file built for OSX, for architecture x86_64

[tamird]

See google/j2objc#611. Looks like the solution is to lipo macOS targets separately from iOS targets (that's what j2objc did: google/j2objc@5be2b44).

Bummer.

[TimNN]

Hi, thanks for the report.

I could not reproduce the issue: I could successfully link to and call into a library build with cargo-lipo (with XCode 7.3.1, tested with iPhone 6S simulator, iPhone 4S simulator & an actual iPhone 6s).

Could you provide me with some more detailed steps on how to reproduce the XCode complaint?

Also, from reading the issue you linked, I believe that the problem should only apply to universal libraries which contains code for both macOS & iOS Simulator. The universal libraries produced by cargo-lipo however never contain code for macOS, they only contain code for the various iOS architectures.

[tamird]

Perhaps I've done something wrong? The project in question is https://github.com/tamird/SwiftyBucket - opening that and running it in XCode 7.3.1 produces the warnings; can you try it locally?

[TimNN]

I tried your project locally:

• I had to fix paths which were hardcoded to your user
• I had turn of the "Enable Bitcode" setting
• I had to manually invoke cargo lipo in the rusty directory (edit: since the cargo invocation as an external tool did not work).

Afterwards your application build & ran without issues on an actual iPhone 6 & the iPhone 6 simulator:

[tamird]

I had to fix paths which were hardcoded to your user

Good call, pushed a commit to fix this.

I had turn of the "Enable Bitcode" setting

How come?

I had to manually invoke cargo lipo in the rusty directory (edit: since the cargo invocation as an external tool did not work).

Fixed this as well.

I thought maybe I had some cached state, so I ran git clean -dxf and recompiled (from xcode) and I still get these warnings.

[TimNN]

I had turn of the "Enable Bitcode" setting

How come?

Because otherwise my build failed (this only happens when building for / running on the actual device, not the simulator targets).

Which rust version are you using (rustc -vV) (I'm using rust stable 1.9.0)?

Where did you install rust and the ios standard library from?

If I understand the linker error correctly, the problems are not directly with the library generated by rust but rather the powidf2.c.o and powisf2.c.o object files which end up in you binary (they are part of the compiler-rt library, which is part of llvm and required by rust libraries).

[TimNN]

Also see rust-lang/rust#29664

[tamird]

Ah, this doesn't happen on 1.9.0, but does on 1.11.0 nightly.

[TimNN]

Alright, so the 2016-06-23 nightly still works, I currently suspect that this was caused by rust-lang/rust#34055. I'm now going to test the next nightly after that pr was merged.

[tamird]

Thanks for tracking this down.

[TimNN]

Reported as rust-lang/rust#34617

[TimNN]

A patch which should fix this issue (rust-lang/rust#34647) has been merged into the rust project and should be included in the next nightly.

I'll keep this issue open until I can verify it has been fixed with an official nightly build.

[TimNN]

@tamird: I can no longer reproduce this issue with the latest nightly, so I'm closing this issue now.

Should it still occur for you, or if you find any other problems, feel free to open another issue.