what is the difference between strong (in LLVM) and retain( in GCC)?

Question

what is the difference between strong (in LLVM compiler) and retain( in GCC compiler) ?

Answer 1

strong is a new feature in iOS 5 Automatic Reference Counting (ARC) which behave the same as retain in iOS 4. Referenced Article.

Also, check out this other SO question: @property definitions with ARC: strong or retain?