Andrei Herford Andrei Herford - 5 months ago 32
iOS Question

Xcode 7 + Dropbox Core API: Simply disable Bitcode?

I have been using Dropbox Core API in my iOS app for quite a while now. After updating to Xcode 7 I received the following error when I try to compile my project:

ld: '.../Frameworks/Dropbox/iOS/DropboxSDK.framework/DropboxSDK' does not contain bitcode.
You must rebuild it with bitcode enabled (Xcode setting ENABLE_BITCODE), obtain an updated
library from the vendor, or disable bitcode for this target.


I know what Bitcode is and what it is good for. The error can be solved by simply setting the
Enable Bitcode
option to
No
in the targets Build Settings. After this everything compiles without any error and the app runs without any problem.

So far so good, but is this the "right" solution? I checked the Dropbox page for an updated Version of the SDK, but I already use the latest version.

The Project contains some other target for an App Widget, Watch Extension, etc. which do not use the Dropbox SDK. What option for
Enable Bitcode
should be used here? Is is (for some reason) better use the same value (
No
in my case) for all targets? Does it make any sense to enable Bitcode for Watch and Widget targets if the the main app target does not use Bitcode?

What is the best practice here?

Answer

Since I asked this question I simply set the option Enable Bitcode to No in the targets Build Settings while using Yes in the Widget and Apple Watch targets. That worked just fine and I did not notice any problems or limitations.

Now I tried to release a new version of my app to the App Store and I noticed a check box Include Bitcode when uploading the app file to Apple. When this check box is enabled I receive the following error:

Invalid Match-O Format. The Match-O bundle "MyApp.app/PlugIns/MyApp WatchKit Extension.appex" isn't consistent with the Match-O in the main bundle.

The main bundle Match-O contains armv7(machine code) and arm64(machine code), while the nested bundle Match-O contains armv7(bitcode and machine code) and arm64(bitcode and machine code).

Varify that all of the targets for a platform have a consistent value for the ENABLE_BITCODE build setting.

I have no idea why this is a problem now while all other version I uploaded during the last year passed without any problem. However the problem can easily be solved by un-checking the Include Bitcode check box. The upload is then accepted without any problem.

But there is a better solution: As Greg pointed out, Dropbox finally released a Bitcode enabled version of the SDK!

Download the new SDK 1.3.14, include it in your project and set ENABLE_BITCODE to Yes for all targets, and you are done. At least until Apple finds a new way to disturb your release workflow :-)