Xcode "Clean Project" causes Shared UE4Editor.app binary to be deleted.
If you check the file system, you can find that the file is actually missing.
You can reinstall the missing UE4Editor.app via Epic Launcher > Select the engine > Verify.
After "Verify", build works again.
I think Xcode clean is removing the shared binary mistakenly.
asked Dec 06 '15 at 10:07 AM in Bug Reports
This still happens in UE 4.15.1 and Xcode 8.3.
I updated to Xcode 8.3, which means my PCH files were compiled with a different branch of the clang compiler. The fix for that is to Clean the project. While this fixed the PCH compiler mismatch issue, it caused several dylib files to be deleted.
If you Verify the Engine in the Epic Game Launcher, it fixes the problem.
This really should get fixed, or at least have a warning come up after cleaning the project from Xcode.
answered May 25 '16 at 05:08 PM
This is a known issue that has been reported and is under investigation (UE-23624).
answered Dec 07 '15 at 01:51 PM
Doug Wilson ♦♦ STAFF
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