Xcode : */swiftc failed with exit code 11, what can I do?

Question

I downloaded Xcode 7 beta 5, and I tried to compile my project with Xcode 7, and it worked. So, after that, I used Xcode 7 to develop my application, but now, I want to back

Answer 1

In my case my submodules were empty which would cause the compiler to crash a simple:

cd /project/file/path
git submodule init
git submodule update

Solved the issue.