dyld: Library not loaded: @rpath/libswiftCore.dylib

Question

I am trying to run a Swift app on my iPhone 4s. It works fine on the simulator, and my friend can successfully run it on his iPhone 4s. I have iOS 8 and the official release of Xcode 6.

I have tried

• Restarting Xcode, iPhone, computer
• Cleaning & rebuilding
• Revoking and creating new certificate/provision profile
• Runpath Search Paths is $(inherited) @executable_path/Frameworks
• Embedded Content Contains Swift Code is 'Yes'
• Code Signing Identity is developer

Below is the error in entirety

dyld: Library not loaded: @rpath/libswiftCore.dylib
  Referenced from: /private/var/mobile/Containers/Bundle/Application/LONGSERIALNUMBER/AppName.app/AppName
  Reason: no suitable image found.  Did find:
    /private/var/mobile/Containers/Bundle/Application/LONGSERIALNUMBER/AppName.app/Frameworks/libswiftCore.dylib: mmap() error 1 at
address=0x008A1000, size=0x001A4000 segment=__TEXT in Segment::map() mapping
/private/var/mobile/Containers/Bundle/Application/LONGSERIALNUMBER/APPLICATION_NAME/Frameworks/libswiftCore.dylib

Answer 1

For me none of the previous solutions worked. We discovered that there is an "Always Embed Swift Standard Libraries" flag in the Build Settings that needs to be set to YES. It was NO by default!

Build Settings > Always Embed Swift Standard Libraries

After setting this, clean the project before building again.

For keen readers some explanation The most important part is:

set the Embedded Content Contains Swift Code (EMBEDDED_CONTENT_CONTAINS_SWIFT) build setting to YES in your app as shown in Figure 2. This build setting, which specifies whether a target's product has embedded content with Swift code, tells Xcode to embed Swift standard libraries in your app when set to YES.

The flag was formerly called Embedded Content Contains Swift Code