I agree that the aliasing control and other features of Rust enable all kinds of interesting optimizations that currently aren't being done, and 'restrict' is o

I agree that the aliasing control and other features of Rust enable all kinds of interesting optimizations that currently aren't being done, and 'restrict' is only part of it. For example we also know that the data behind a shared reference is really immutable (apart from UnsafeCell etc). Unfortunately we may need an entirely new generation of compiler infrastructure to exploit these opportunities because LLVM is really a C/C++ compiler at heart and may not be happy about taking big changes that can't benefit C/C++.