On: How copying an int made my code 11 times faster

[msbarnett]

Am I reading it right? It looks to me like rustc didn't mark the immutable borrow as readonly, so LLVM went ahead and assumed print could mutate it.

[dbaupp → msbarnett]

I'm not 100% sure, but I believe LLVM doesn't have a way to understand the (im)mutability of pointers rewritten into memory, like the borrow is here.