I ran into some network issue that caused the clang patch to not download and the script exited. A retry would have solved it. The fallback choice, wget, has a default 20 retries.
I chose 5 retries because curl backs of after each try, starting at one second and doubling each time. 5 retries means that worst case scenario would be a total of 31 seconds waiting between attempts. IMO that should be enough tries if internet is working, but not too much if internet is not working.