What causes "clang failed with exit code 255" in Xcode IDE?

Question

Other users have asked about "clang exit code 255" before, such as in this post:

Xcode not compiling any project? 'clang failed with exit code 255'

I know how to fix the error. This usually does it:

• Clean the project
• Go to 'Window > Organizer > Project > Delete Derived Data'
• Restart Xcode
• Fixed, like magic...

However, I don't know what causes it, and lately, it's been happening a lot (which is frustrating because it's time consuming).

Anyone know what causes this error and how to prevent it from happening?

Answer 1

Closing and restarting the simulator usually clears this error.